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Subtype-targeted therapies can have a dramatic impact on improving the quality and quantity of life for women suffering from breast cancer. Despite an initial therapeutic response, cancer recurrence and acquired drug-resistance are commonplace. Non-invasiv

Hypothesis: Ginseng root extracts and the biologically active ginsenosides have been shown to inhibit proliferation of human cancer cell lines, including breast cancer. However, there are conflicting data that suggest that ginseng extracts (GEs) may or may not have estrogenic action, which might be contraindicated in individuals with estrogen-dependent cancers. The current study was designed to address the hypothesis that the extraction method of American ginseng (Panax quinquefolium) root will dictate its ability to produce an estrogenic response using the estrogen receptor (ER)-positive MCF-7 human breast cancer cell model. METHODS: MCF-7 cells were treated with a wide concentration range of either methanol-(alc-GE) or water-extracted (w-GE) ginseng root for 6 days. Cells were grown in media containing either normal or charcoal-stripped fetal calf serum to limit exposure to exogenous estrogen. Thus, an increase in MCF-7 cell proliferation by GE indicated potential estrogenicity. This was confirmed by blocking GE-induced MCF-7 cell proliferation with ER antagonists ICI 182,780 (1 nM) and 4-hydroxytamoxifen (0.1 microM). Furthermore, the ability of GE to bind ERalpha or ERbeta and stimulate estrogen-responsive genes was examined. RESULTS: Alc-GE, but not w-GE, was able to increase MCF-7 cell proliferation at low concentrations (5-100 mcirog/mL) when cells were maintained under low-estrogen conditions. The stimulatory effect of alc-GE on MCF-7 cell proliferation was blocked by the ER antagonists ICI 182,780 or 4-hydroxyta-moxifen. At higher concentrations of GE, both extracts inhibited MCF-7 and ER-negative MDA-MB-231 cell proliferation regardless of media conditions. Binding assays demonstrated that alc-GE, but not w-GE, was able to bind ERalpha and ERbeta. Alc-GE (50 microg/mL) also induced an approximate 2.5-fold increase in expression of the estrogen-responsive pS2 gene, as well as progesterone receptor (PgR) gene expression, whereas w-GE was without effect. CONCLUSION: These data indicate that low concentrations of alc-GE, but not w-GE, elicit estrogenic effects, as evidenced by increased MCF-7 cell proliferation, in a manner antagonized by ER antagonists, interactions of alc-GE with estrogen receptors, and increased expression of estrogen-responsive genes by alc-GE. Thus, discrepant results between different laboratories may be due to the type of GE being analyzed for estrogenic activity. [ABSTRACT FROM AUTHOR]

Background: Bupropion is associated with a dose-dependent increased risk of seizures. Use of concomitant bupropion and electroconvulsive therapy (ECT) remains controversial because of an increased risk of prolonged seizures. This is the first systematic evaluation of the effect of bupropion on ECT., Methods: A case group (n = 119), patients treated with concomitant ECT and bupropion, was compared with an age and gender frequency-matched control group (n = 261), treated with only ECT. Electroconvulsive therapy treatment data including seizure length, number of treatments, and concurrent medications were extracted. Longitudinal mixed models examined ECT versus ECT + bupropion group differences over the course of treatments measured by seizure duration (electroencephalogram [EEG] and motor). Multivariable models examined the total number of treatments and first and last seizure duration. All models considered group differences with ECT treatment measures adjusted for age, gender, benzodiazepine treatment, lead placement, and setting., Results: Electroconvulsive therapy treatment with bupropion led to shorter motor seizure duration (0.047) and EEG seizure duration (P = 0.001). The number of ECT treatments (7.3 vs 7.0 treatments; P = 0.23), respectively, or the probability of a prolonged seizure (P = 0.15) was not significantly different. Benzodiazepine use was significantly more common in control subjects (P = 0.01)., Limitations: This is a retrospective analysis limited in part by unavailable variables (seizure threshold, nature of EEG and motor seizure monitoring, type of ECT device, dosing and formulation of bupropion, and duration of the current depressive illness)., Conclusions: This study revealed a significantly shorter duration in seizure length with ECT + concomitant bupropion, but not in the number of required treatments in those treated compared with ECT without bupropion. There remains a critical need to reevaluate the efficacy of concomitant use of psychotropic medications + ECT.

Abnormalities in glutamate neurotransmission may have a role in the pathophysiology of adolescent depression. The present pilot study examined changes in cortical glutamine/glutamate ratios in depressed adolescents receiving high-frequency repetitive transcranial magnetic stimulation. Ten adolescents with treatment-refractory major depressive disorder received up to 30 sessions of 10-Hz repetitive transcranial magnetic stimulation at 120% motor threshold with 3000 pulses per session applied to the left dorsolateral prefrontal cortex. Baseline, posttreatment, and 6-month follow-up proton magnetic resonance spectroscopy scans of the anterior cingulate cortex and left dorsolateral prefrontal cortex were collected at 3T with 8-cm(3) voxels. Glutamate metabolites were quantified with 2 distinct proton magnetic resonance spectroscopy sequences in each brain region. After repetitive transcranial magnetic stimulation and at 6 months of follow-up, glutamine/glutamate ratios increased in the anterior cingulate cortex and left dorsolateral prefrontal cortex with both measurements. The increase in the glutamine/glutamate ratio reached statistical significance with the TE-optimized PRESS sequence in the anterior cingulate cortex. Glutamine/glutamate ratios increased in conjunction with depressive symptom improvement. This reached statistical significance with the TE-optimized PRESS sequence in the left dorsolateral prefrontal cortex. High-frequency repetitive transcranial magnetic stimulation applied to the left dorsolateral prefrontal cortex may modulate glutamate neurochemistry in depressed adolescents., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Phytonutrients have rapidly emerged as natural food chemicals possessing multifaceted biological actions that may support beneficial health outcomes. Among the vast array of phytonutrients currently being studied, sulforaphane, curcumin, quercetin, and resveratrol have been frequently reported to stimulate the expression of endogenous detoxification enzymes and may thereby facilitate the neutralization of otherwise harmful environmental agents. Some of these same phytonutrients, however, have also been implicated in disrupting normal cell proliferation and hence may possess toxic properties in and of themselves. In this study, we characterize the respective minimum threshold concentrations of the aforementioned phytonutrients in Hepa1c1c7 cells that stimulate, Nad(p)h: quinone oxidoreductase (NQO1), a key enzyme in the hepatic neutralization of menadione, other biological oxidants, and some environmental carcinogens. Moreover, our findings demonstrate that relatively low concentrations of either sulforaphane or curcumin significantly (P < .05) increase NQO1 protein expression and activity without triggering G2/M cell cycle arrest or mitotic catastrophe. The minimal quercetin concentration inducing NQO1, however, was 100-fold higher than that which disrupted mitosis. Also, while resveratrol modestly stimulated NQO1, the minimally effective resveratrol concentration concomitantly induced evidence of cellular apoptosis. Taken together, these findings indicate that only particular phytonutrients are likely efficacious in upregulating NQO1 activity without also leading to hepatic cytotoxicity.

Background: Worldwide, rural communities face barriers when accessing health services. In response, numerous initiatives have focused on fostering technological innovations, new management approaches and health policies. Research suggests that the most successful innovations are those involving stakeholders at all levels. However, there is little evidence exploring the opinions of local health providers that could contribute with further innovation development and research. The aims of this study were to explore the perspectives of medical doctors (MDs) working in rural areas of Peru, regarding the barriers impacting the diagnostic process, and ideas for diagnostic innovations that could assist them., Methods: Data gathered through three focus group discussions (FGG) and 18 individual semi-structured interviews (SSI) with MDs who had completed their medical service in rural areas of Peru in the last two years were analyzed using thematic analysis., Results: Three types of barriers emerged. The first barrier was the limited access to point of care (POC) diagnostic tools. Tests were needed for: i) the differential diagnosis of malaria vs. pneumonia, ii) dengue vs. leptospirosis, iii) tuberculosis, iv) vaginal infections and cervical cancer, v) neurocysticercosis, and vi) heavy metal toxicity. Ultrasound was needed for the diagnosis of obstetric and intra-abdominal conditions. There were also health system-related barriers such as limited funding for diagnostic services, shortage of specialists, limited laboratory services and access to telecommunications, and lack of institutional support. Finally, the third type of barriers included patient related-barriers to follow through with diagnostic referrals. Ideas for innovations proposed included POC equipment and tests, and telemedicine., Conclusions: MDs at primary health facilities in rural Peru face diagnostic challenges that are difficult to overcome due to a limited access to diagnostic tools. Referrals to specialized facilities are constrained by deficiencies in the organization of health services and by barriers that impede the patients' travel to distant health facilities. Technological innovations suggested by the participants such as POC diagnostic tools and mobile-health (m-health) applications could help address part of the problem. However, other types of innovation to address social, adaptation and policy issues should not be dismissed.

Background: Pharmacologic strategies are often required to help manage agitated patients with delirium. First-and second-generation antipsychotic medications (such as haloperidol, quetiapine, and olanzapine) are commonly used., Objective: On the psychiatric consultation service in our hospital, thiothixene has been used based on its favorable potency, sedative, and cost profiles. Little has been written about the utility of this drug for management of delirium., Methods: We reviewed our experience with thiothixene in this setting using pharmacy records to identify patients who received at least 1 dose between July 2011 and March 2014. We scrutinized the relevant medical records (n = 111) and recorded the following data: age, sex, medical diagnoses, signs and symptoms of delirium, dosing of thiothixene, and response to thiothixene in terms of both apparent benefit as well as side effects., Results: Resolution or improvement was documented in 78% of patients and good tolerability in 82% of patients., Conclusions: Although further data from a randomized, controlled trial would be ideal, our experience suggests that thiothixene could be a safe and effective pharmacologic treatment for agitation and psychosis due to delirium., (Copyright © 2015 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.)

Background: Calmodulin (CaM) mutations have been identified recently in subjects with congenital long QT syndrome (LQTS) or catecholaminergic polymorphic ventricular tachycardia (CPVT), but the mechanisms responsible for these divergent arrhythmia-susceptibility syndromes in this context are unknown. We tested the hypothesis that LQTS-associated CaM mutants disrupt Ca2+ homeostasis in developing cardiomyocytes possibly by affecting either late Na current or Ca2+-dependent inactivation of L-type Ca2+ current., Methods and Results: We coexpressed CaM mutants with the human cardiac Na channel (NaV1.5) in tsA201 cells, and we used mammalian fetal ventricular cardiomyocytes to investigate LQTS- and CPVT-associated CaM mutations (LQTS- and CPVT-CaM). LQTS-CaM mutants do not consistently affect L-type Na current in heterologous cells or native cardiomyocytes, suggesting that the Na channel does not contribute to LQTS pathogenesis in the context of CaM mutations. LQTS-CaM mutants (D96V, D130G, F142L) impaired Ca2+-dependent inactivation, whereas the CPVT-CaM mutant N54I had no effect on Ca2+-dependent inactivation. LQTS-CaM mutants led to loss of Ca2+-transient entrainment with the rank order from greatest to least effect: CaM-D130G~CaM-D96V>>CaM-F142L. This rank order follows measured Ca2+-CaM affinities for wild-type and mutant CaM. Acute isoproterenol restored entrainment for CaM-130G and CaM-D96V but caused irreversible cytosolic Ca2+ overload for cells expressing a CPVT-CaM mutant., Conclusions: CaM mutations associated with LQTS may not affect L-type Na+ current but may evoke defective Ca2+-dependent inactivation of L-type Ca2+ current., (© 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

Rathke's cleft cysts (RCC) are usually benign, sellar and/or suprasellar lesions originating from the remnants of Rathke's pouch. Rarely, RCC can present with chemical meningitis, sellar abscess, lymphocytic hypophysitis, or intracystic hemorrhage. We describe an unusual presentation of RCC in which the patient presented with a clinical picture of chemical meningitis consisting of meningeal irritation, inflammatory cerebrospinal fluid profile, and enhancing pituitary and hypothalamic lesions, in addition to involvement of the optic tracts and optic nerve., (Published by Elsevier Ltd.)

Subtype-targeted therapies can have a dramatic impact on improving the quality and quantity of life for women suffering from breast cancer. Despite an initial therapeutic response, cancer recurrence and acquired drug-resistance are commonplace. Non-invasive imaging probes that identify drug-resistant lesions are urgently needed to aid in the development of novel drugs and the effective utilization of established therapies for breast cancer. The protease receptor urokinase plasminogen activator receptor (uPAR) is a target that can be exploited for non-invasive imaging. The expression of uPAR has been associated with phenotypically aggressive breast cancer and acquired drug-resistance. Acquired drug-resistance was modeled in cell lines from two different breast cancer subtypes, the uPAR negative luminal A subtype and the uPAR positive triple negative subtype cell line MDA-MB-231. MCF-7 cells, cultured to be resistant to tamoxifen (MCF-7 TamR), were found to significantly over-express uPAR compared to the parental cell line. uPAR expression was maintained when resistance was modeled in triple-negative breast cancer by generating doxorubicin and paclitaxel resistant MDA-MB-231 cells (MDA-MB-231 DoxR and MDA-MB-231 TaxR). Using the antagonistic uPAR antibody 2G10, uPAR was imaged in vivo by near-infrared (NIR) optical imaging and (111)In-single photon emission computed tomography (SPECT). Tumor uptake of the (111)In-SPECT probe was high in the three drug-resistant xenografts (> 46 %ID/g) and minimal in uPAR negative xenografts at 72 hours post-injection. This preclinical study demonstrates that uPAR can be targeted for imaging breast cancer models of acquired resistance leading to potential clinical applications.

Objectives: It is estimated that 30-40% of adolescents with major depressive disorder (MDD) do not receive full benefit from current antidepressant therapies. Repetitive transcranial magnetic stimulation (rTMS) is a novel therapy approved by the US Food and Drug Administration to treat adults with MDD. Research suggests rTMS is not associated with adverse neurocognitive effects in adult populations; however, there is no documentation of its neurocognitive effects in adolescents. This is a secondary post hoc analysis of neurocognitive outcome in adolescents who were treated with open-label rTMS in two separate studies., Methods: Eighteen patients (mean age, 16.2 ± 1.1 years; 11 females, 7 males) with MDD who failed to adequately respond to at least one antidepressant agent were enrolled in the study. Fourteen patients completed all 30 rTMS treatments (5 days/week, 120% of motor threshold, 10 Hz, 3,000 stimulations per session) applied to the left dorsolateral prefrontal cortex. Depression was rated using the Children's Depression Rating Scale-Revised. Neurocognitive evaluation was performed at baseline and after completion of 30 rTMS treatments with the Children's Auditory Verbal Learning Test (CAVLT) and Delis-Kaplan Executive Function System Trail Making Test., Results: Over the course of 30 rTMS treatments, adolescents showed a substantial decrease in depression severity. Commensurate with improvement in depressive symptoms was a statistically significant improvement in memory and delayed verbal recall. Other learning and memory indices and executive function remained intact. Neither participants nor their family members reported clinically meaningful changes in neurocognitive function., Conclusion: These preliminary findings suggest rTMS does not adversely impact neurocognitive functioning in adolescents and may provide subtle enhancement of verbal memory as measured by the CAVLT. Further controlled investigations with larger sample sizes and rigorous trial designs are warranted to confirm and extend these findings.

Curcumin, a component of turmeric spice that imparts flavor and color to curry, is thought to possess anti-inflammatory and antioxidant properties in biological tissues. However, while such efficacies have been described in the context of carcinogenesis, the impact of curcumin on normal cell cycle regulation is poorly understood. Here, we provide evidence of curcumin toxicity in proliferating bovine aortic endothelial cells, at concentrations relevant to the diet and below those previously reported in cancer models. Upon confirming curcumin's ability to upregulate hemeoxygenase-1 in a dose-dependent fashion, we found the minimally efficacious curcumin concentration to also inhibit endothelial cell DNA synthesis. Moreover, curcumin concentrations below the minimum 2 μM threshold required to induce hemeoxygenase-1 bound tubulin protein in vitro and triggered hallmark evidence of mitotic catastrophe in vivo. Concentrations as low as 0.1 μM curcumin led to disproportionate DNA segregation, karyorrhexis, and micronucleation in proliferating endothelial cells. While suggesting a mechanism by which physiological curcumin concentrations inhibit cell cycle progression, these findings describe heretofore unappreciated curcumin toxicity with potential implications for endothelial growth, development, and tissue healing., (Published by Elsevier Ltd.)

Background: Congenital long-QT syndrome (LQTS) may present during fetal development and can be life-threatening. The molecular mechanism for the unusual early onset of LQTS during fetal development is unknown., Objective: We sought to elucidate the molecular basis for severe fetal LQTS presenting at 19 weeks' gestation, the earliest known presentation of this disease., Methods: Fetal magnetocardiography was used to demonstrated torsades de pointes and a prolonged rate-corrected QT interval. In vitro electrophysiological studies were performed to determine functional consequences of a novel SCN5A mutation found in the fetus., Results: The fetus presented with episodes of ventricular ectopy progressing to incessant ventricular tachycardia and hydrops fetalis. Genetic analysis disclosed a novel, de novo heterozygous mutation (L409P) and a homozygous common variant (R558 in SCN5A). In vitro electrophysiological studies demonstrated that the mutation in combination with R558 caused significant depolarized shifts in the voltage dependence of inactivation and activation, faster recovery from inactivation, and a 7-fold higher level of persistent current. When the mutation was engineered in a fetal-expressed SCN5A splice isoform, channel dysfunction was markedly potentiated. Also, R558 alone in the fetal splice isoform evoked a large persistent current, and hence both alleles were dysfunctional., Conclusion: We report the earliest confirmed diagnosis of symptomatic LQTS and present evidence that mutant cardiac sodium channel dysfunction is potentiated by a developmentally regulated alternative splicing event in SCN5A. Our findings provide a plausible mechanism for the unusual severity and early onset of cardiac arrhythmia in fetal LQTS., (Copyright © 2012 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Ethnopharmacological Relevance: Ginseng is a widely consumed aromatic herb that is purported to have health benefits. Several studies report a beneficial impact of ginseng or its derivatives on Candida albicans infection in mice and suggest that its immune-modulatory properties contribute to this effect. However, these studies generally administered ginseng to experimental animals by injection, whereas people typically ingest ginseng. Furthermore, although disseminated candiasis is typically a disease of immune-impaired hosts, previous studies have generally used immune competent host species in the assessments., Materials and Methods: We evaluated the efficacy of an ingested extract of ginseng against Candida albicans infection in DBA/2J mice, which are highly susceptible to Candida albicans infection. A ginseng extract was added to the drinking water for two days before and for the remainder of the study after intravenous inoculation of mice with Candida albicans. Mice were evaluated for morbidity, mortality, Candida albicans titers, and concentrations of inflammatory cytokines and chemokines., Results: Ingestion of the ginseng extract did not significantly affect overall morbidity or mortality. However, ingestion of the extract was associated with significantly lower renal titers of Candida albicans and with significantly lower concentrations of some inflammatory cytokines in kidney and/or serum., Conclusions: Assessment of morbidity, mortality, inflammatory markers, and renal titers after spontaneous ingestion of ginseng by susceptible hosts represents a comprehensive approach to characterizations of therapeutic efficacy against infectious agents. Our findings extend previous reports of the efficacy of ginseng against Candida albicans by demonstrating significant reductions in infectious load and some markers of inflammation in susceptible mice. Our data therefore support further assessment of the immune-modulatory properties of this widely consumed herb and its components., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

We previously isolated cacalol as a free radical-scavenging compound from Cacalia delphiniifolia which is a traditional Asian herbal plant and is believed to have medicinal effects on cancer. In this report, we demonstrated that cacalol has strong anti-proliferation effect on breast cancer cells and induces apoptosis by activating a pro-apoptotic pathway. We also found that a combination of cacalol and other chemotherapeutic drugs (Taxol and cyclophosphamide) synergistically induced apoptosis and partially overcame chemo-resistance. To further gain a mechanistic insight, we tested a potential inhibitory effect of cacalol on fatty acid synthase gene (FAS) in breast cancer cells, and found that cacalol significantly modulated the expression of the FAS gene, which resulted in apoptosis through activation of DAPK2 and caspase 3. We have also shown that cacalol significantly suppressed the Akt-sterol regulatory element-binding proteins (SREBP) signaling pathway and concomitant transcriptional activation of FAS. In a xenograft model of nude mouse, when cacalol was administered intraperitoneally, tumor growth was significantly suppressed. Importantly, oral administration of cacalol before implanting tumors showed significant preventive effect on tumor growth in the same animal model. Furthermore, the treatment of mice with a combination of low dose of Taxol and cacalol significantly suppressed the tumor growth. Taken together, our results indicate that cacalol induces apoptosis in breast cancer cells and impairs mammary tumor growth in vivo by blocking the expression of the FAS gene through modulation of Akt-SREBP pathway, suggesting that cacalol has potential utility as a chemopreventive and chemotherapeutic agent for breast cancer.

Background: Outpatient hysteroscopy is increasingly being used as a cost-effective alternative to in-patient hysteroscopy under general anaesthesia. Like other outpatient gynaecological procedures, however, it has the potential to cause pain severe enough for the procedure to be abandoned. There are no national guidelines on pain relief for outpatient hysteroscopy., Methods: A postal survey of UK gynaecologists was carried out to evaluate current clinical practice regarding methods of pain relief used during office hysteroscopy. A total of 250 questionnaires were sent out and 115 responses received., Results: Outpatient hysteroscopy was offered by 76.5% of respondents. Respondents reported a wide variation in the use of routine and rescue analgesia, and also in the nature of the analgesia used. One-quarter of those offering outpatient hysteroscopy used no form of analgesia., Conclusion: The results showed that whilst there is no consensus on the type of analgesia provided, rescue analgesia is commonly being used, particularly in the form of intracervical blocks., (Copyright © 2010. Published by Elsevier Ireland Ltd.)

The behavior of dense, viscous calcium bromide brine solutions used to remediate systems contaminated with dense nonaqueous phase liquids (DNAPLs) is considered in laboratory and field porous medium systems. The density and viscosity of brine solutions are experimentally investigated and functional forms fit over a wide range of mass fractions. A density of 1.7 times, and a corresponding viscosity of 6.3 times, that of water is obtained at a calcium bromide mass fraction of 0.53. A three-dimensional laboratory cell is used to investigate the establishment, persistence, and rate of removal of a stratified dense brine layer in a controlled system. Results from a field-scale experiment performed at the Dover National Test Site are used to investigate the ability to establish and maintain a dense brine layer as a component of a DNAPL recovery strategy, and to recover the brine at sufficiently high mass fractions to support the economical reuse of the brine. The results of both laboratory and field experiments show that a dense brine layer can be established, maintained, and recovered to a significant extent. Regions of unstable density profiles are shown to develop and persist in the field-scale experiment, which we attribute to regions of low hydraulic conductivity. The saturated-unsaturated, variable-density groundwater flow simulation code SUTRA is modified to describe the system of interest, and used to compare simulations to experimental observations and to investigate certain unobserved aspects of these complex systems. The model results show that the standard model formulation is not appropriate for capturing the behavior of sharp density gradients observed during the dense brine experiments., (2010 Elsevier B.V. All rights reserved.)

American ginseng and its ginsenoside constituents have been shown to exert anti-cancer effects although the mechanism of action remains unclear. The present study determined the effects of water-extracted ginseng (GE) or its ginsenoside (GF) and polysaccharide (PS) fractions on the proliferation of human colon cancer cells and examined the role of p21 in mediating these effects using wild-type and p21-/- HCT116 human colon carcinoma cells. Proliferation was inhibited by GE, GF, and PS in wild-type and p21-/- cells, and the p21-/- cells were more sensitive to these treatments. Wild type cells treated with GE were arrested in the G0/G1 phase of the cell cycle and the expression of p53 and p21 proteins was increased while phospho-MEK levels decreased. In contrast, cells deficient in p21 displayed reduced cell viability, elevated number of dead cells, and increased expression of Bax and cleaved caspase-3 proteins. Both polysaccharides and ginsenosides appear to be responsible for the anti-proliferative and proapoptotic effects of GE. This study suggests that p21 functions to arrest HCT116 wild-type cells treated with GE, while p21-deficient cells undergo cell death in a ginseng constituent-dependent manner., (Copyright 2009 Elsevier GmbH. All rights reserved.)

Background: Epidemiologic evidence suggests reduced breast cancer mortality in users of American Ginseng (AG) (Panax quinquefolium). We hypothesized that AG extract decreases proliferation of human breast cancer cells via an anti-inflammatory effect applicable to the prevention of breast and other cancers., Material and Methods: A defined lyophilized aqueous extract of AG (LEAG) was dissolved in DMSO 1mg/mL, and serially diluted in saline. The cell lines MDA MB 231 and MCF7 were stimulated with the phorbol ester PDBu and treated with 100-500 mcg/mL LEAG. Proliferation was measured by MDA assay. Induced COX-2 expression was assayed by ELISA. Activation of NFkappaB by phosphorylation of the p65 subunit was quantified by CASE (cellular activation of signaling ELISA)., Results: Both cell lines had reduced proliferation when treated with LEAG. PDBu stimulation of MDA MB 231 increased expression of the COX-2 protein 20-fold at 48 hours (P<0.005). COX-2 protein expression remained at baseline concentrations in PDBu- treated MDA MB 231 cells exposed to 100 mcg/mL LEAG. The CASE assay showed a 4-fold increase in p65 activation 24 hours after PDBu treatment in normal medium, while phosphorylated p65 dropped below baseline in the cells treated with PDBu plus LEAG., Conclusion: In MDA MB 231, COX-2 was inducible with PDBu. This induced COX-2 expression was blocked by 100 microgram/mL LEAG in a time course consistent with the decline in the activated p65 subunit of NFkappaB. These results provide an anti-inflammatory mechanism for a possible anti-cancer effect of American Ginseng.

Ginseng has been shown to inhibit cancer cell proliferation and tumor growth, however the mechanisms underlying this inhibition have yet to be elucidated. An inhibitory effect of hot water-extracted American ginseng (Panax quinquefolius L.) root on cell proliferation was demonstrated using MCF-7 human breast cancer cells treated with a wide concentration range of the ginseng extract (GE) for 6 days. The effects of GE were concentration-dependent with an IC50 of 0.49 microg/microl and the minimum exposure time to elicit an inhibitory response was 24 hours. Using an antibody microarray, it was determined that several key cell survival proteins were altered in GE-treated cells, including several members of the mitogen-activated protein kinase (MAPK) family. A GE-induced decrease in phospho-MEK1/2 and -ERK1/2 and an increase in phospho-Raf-1 were observed and verified using Western blot analysis. Furthermore, mRNA and protein expression of the Raf-1 kinase inhibitor protein (RKIP) was shown to be transiently, yet significantly, upregulated following GE treatment. These results suggest that American ginseng may act to inhibit breast cancer cell proliferation by increasing the expression of RKIP, resulting in inhibition of the MAPK pathway. This novel mechanism has implications in the potential prevention and treatment of breast cancer.

American ginseng root (Panax quinquefolius) has a number of purported therapeutic effects, including inhibition of cancer cell proliferation. The ability of environmentally relevant heavy metals to alter ginseng effects on cancer cell growth was the subject of this study. A water extract of American ginseng root was applied alone or in combination with physiologically relevant doses of either lead (Pb) or arsenite to MCF-7 breast cancer cells in vitro and effects on cell proliferation were determined. Ginseng alone produced a significant dose-dependent inhibition of MCF-7 cell proliferation starting at 0.5 mg ml(-1). Treatment of MCF-7 cells with 2.5 microM arsenite significantly decreased MCF-7 cell proliferation (p < 0.01). When cells were treated with arsenite (1.25 or 2.5 microM) in combination with ginseng extract (0.5 mg ml(-1)), there was an apparent synergistic inhibition of cell proliferation. Treatment of MCF-7 breast cancer cells with 50 microM Pb significantly decreased cell proliferation relative to control (p < 0.01), and concomitant ginseng and Pb treatment did not lead to a further decrease. These results suggest that contaminant heavy metals, some of which have been detected in ginseng root extracts or commercial ginseng preparations, may alter the biological activity of ginseng.

Four methods were tested for extraction and recovery of six major ginsenosides (Rb1, Rb2, Rc, Rd, Re, and Rg1) found in roots of American ginseng (Panax quinquefolius): method A, sonication in 100% methanol (MeOH) at room temperature (rt); method B, sonication in 70% aqueous MeOH at rt; method C, water extraction (90 degrees C) with gentle agitation; and method D, refluxing (60 degrees C) in 100% MeOH. After 0.5-1 h, the samples were filtered and analyzed by high-performance liquid chromatography (HPLC)-UV. A second extraction by methods C and D was done, but 85-90% of ginsenosides were obtained during the first extraction. Lyophilization of extracts did not influence ginsenoside recovery. Method D resulted in the highest significant recoveries of all ginsenosides, except Rg1. Method C was the next most effective method, while method A resulted in the lowest ginsenoside recoveries. Method B led to similar recoveries as method C. All methods used one filtration step, omitted time-consuming cleanup, but maintained clear peak resolution by HPLC, and can be used for quantitative screening of ginsenosides from roots and commercial ginseng preparations.

Dopamine (DA) agonist and antagonist treatments can affect ovarian reproductive events in the mare. To support our theory that DA produces these effects by acting directly on the ovary, we analyzed equine ovarian tissues for the presence of dopamine receptor-1 (D1r) and dopamine receptor-2 (D2r) mRNA by reverse transcription polymerase chain reaction (RT-PCR) and D1r and D2r proteins by Western blot and immunohistochemistry (IHC). RT-PCR was performed on RNA isolated from ovarian cortex, medulla, granulosa/theca or corpus luteum (CL) tissues and from pituitary (D2r control) and renal artery (D1r control). D1r and D2r specific primers were designed from partial DNA sequences known for the horse (D2r) or conserved sequences from other species (D1r). Western blot analyses were conducted on CL, cortex and granulosa/theca samples and IHC was performed on CL tissues using D1r or D2r specific antibodies. The incidence of positive D2r mRNA was high in CL and ovarian cortex, low in granulosa/theca, and not detectable in ovarian medulla. Dopamine D1r mRNA incidence was high (50%) only in CL tissues. D1r and D2r antibody staining was positive for each tissue type analyzed by Western blot procedures. All CL tissues prepared by IHC showed positive staining for D1r and D2r proteins. Both DA receptor proteins appeared uniformly distributed throughout the CL tissue. These results indicate that equine ovarian tissues do possess D1r and D2r, and suggests that DA can act directly on ovarian tissues through its interaction with DA receptors.

Objective: To determine the genetic differences between African Americans (AA) and Non-African Americans (NAA) with head and neck squamous cell carcinoma (HNSCC)., Methods: DNA was obtained from tumor tissues and peripheral blood from 18 AA and 19 NAA patients with HNSCC. Microsatellite analysis using a fluorescent technique was performed on chromosomal arms 1p, 3p, 4q, 9p, 13q, and 17p. Statistical analyses were performed on the molecular and clinical outcome data., Results: Based on the Surveillance, Epidemiologic, and End Result (SEER) data from southeast Michigan, the incidence rate of HNSCC in AA has been higher than for NAA, and the overall 5-year relative survival rate is lower for AA than NAA (36.2% vs. 47.6%). In this study, we found that the rate of loss of heterozygosity of chromosomal arms 1p, 3p, 4q, 9p, 13q, and 17p ranged from 68.8% to 83.3% for HNSCC in AA and from 66.7% to 90.0% in NAA. The difference in the rates of microsatellite alterations in chromosomal arms 3p, 4q, and 9p between AA and NAA were between 12.5% and 20% and were not statistically significant., Conclusion: The incidence and clinical outcomes for AA with HNSCC are different from that of NAA in southeast Michigan. In our group of patients with HNSCC, differences in rates of microsatellite alterations and survival were found between AA and NAA; however, these differences were not statistically significant. We conclude that genetic difference, as determined by the rates of microsatellite alterations, is not predictive of outcome difference between AA and NAA HNSCC patients.

T cells resistant to the immunosuppressive drug cyclosporin A (CsA) may be important mediators of chronic graft rejection. We previously reported that T cells activated in the presence of endothelial cells (EC) develop resistance to CsA, and initiate IL-2 secretion within 8-12 h of triggering. CsA normally blocks the phosphatase, calcineurin, thus preventing nuclear translocation of the transcription factor, NFAT. We find that in the presence but not the absence of EC, NFAT1 can be detected in the nuclei of CsA-treated T cells within 8 h of triggering, reaching a maximal level of 60% of control by 24 h. Glycogen synthase kinase-3beta (GSK-3beta), which rephosphorylates NFAT and promotes nuclear export, is inhibited by EC costimulation. GSK-3beta is a component of the wnt signaling pathway, and EC express wnt-5a and T cells express frizzled-5, a wnt-5a receptor. Wnt-5a promotes T cell NFAT nuclear accumulation in the presence of CsA, an effect mimicked by Li(+), a potent inhibitor of GSK-3beta. The protein kinase C agonist PMA dramatically synergizes with both EC and wnt-5a in stimulating T cell IL-2 synthesis, and inhibition of either protein kinase C by Ro-31-8425 or G-proteins by pertussis toxin effectively blocks the actions of wnt-5a on T cells. Finally, a secreted, dominant-negative form of frizzled-5 blocks EC-mediated CsA resistance. Thus, EC promote CsA-resistant nuclear localization of NFAT and subsequent IL-2 synthesis through a noncanonical wnt-dependent pathway.

In Asia, ginseng is commonly included in herbals used for the treatment of sexual dysfunction. Recent studies in laboratory animals have shown that both Asian and American forms of ginseng enhance libido and copulatory performance. These effects of ginseng may not be due to changes in hormone secretion, but to direct effects of ginseng, or its ginsenoside components, on the central nervous system and gonadal tissues. Indeed, there is good evidence that ginsenosides can facilitate penile erection by directly inducing the vasodilatation and relaxation of penile corpus cavernosum. Moreover, the effects of ginseng on the corpus cavernosum appear to be mediated by the release and/or modification of release of nitric oxide from endothelial cells and perivascular nerves. Treatment with American ginseng also affects the central nervous system and has been shown to significantly alter the activity of hypothalamic catecholamines involved in the facilitation of copulatory behavior and hormone secretion. Recent findings that ginseng treatment decreased prolactin secretion also suggested a direct nitric oxide-mediated effect of ginseng at the level of the anterior pituitary. Thus, animal studies lend growing support for the use of ginseng in the treatment of sexual dysfunction and provide increasing evidence for a role of nitric oxide in the mechanism of ginsenoside action.

Peripheral administration of cannabinoid CB1 receptor agonists to laboratory rats induce a brief rise in plasma prolactin (PRL) levels followed by a prolonged decrease in PRL secretion from the pituitary. While the inhibitory component of this biphasic response depends on the cannabinoid-induced activation of dopamine release from hypothalamic terminals located in the median eminence, the neurobiological mechanisms underlying the activation phase of PRL release remains to be explained. In the present study the possible direct effect of the cannabinoid receptor agonist delta9-Tetrahydrocannabinol (THC) on prolactin secretion and cAMP accumulation was examined in anterior pituitary cultures. THC (0.1 and 1 microM) increased cAMP levels, and induced PRL release (1 and 10 mu). THC did not affect vasoactive intestinal peptide (VIP, 0.5 microM) induced cAMP accumulation in pituitary cultures, showing additive effects at THC 1 microM concentration. However, THC did prevent VIP-dependent increases in prolactin secretion. These results indicate that THC, through a direct pituitary action, activates both the synthesis of cAMP and PRL release and interferes with intracellular mechanisms involved in PRL secretion by VIP. These actions could be mediated through cannabinoid CB1 receptors which were found to be present in anterior pituitary cells, including lactotrophs, as revealed by immunocytochemistry with a specific polyclonal antibody raised against the CB1 receptor protein.

Acute treatment with delta9-tetrahydrocannabinol [delta9-THC; 0.5 or 1.0 mg/kg b.w. intravenously (i.v.)], the major psychoactive constituent of marijuana, produces a dose-related suppression of pulsatile luteinizing hormone (LH) secretion in ovariectomized rats. To determine whether delta9-THC produces this response by altering neurotransmitter and/or neuropeptide systems involved in the regulation of LH secretion, ovariectomized rats were pretreated with antagonists for dopamine, norepinephrine, serotonin, or opioid receptors, and the effect of delta9-THC on LH release was determined. Pretreatment with the D2 receptor antagonists butaclamol (1.0 mg/kg b.w., intraperitoneally) or pimozide [0.63 mg/kg, subcutaneously (s.c.)], the opioid receptor antagonists naloxone (1-4 mg/kg, i.v.) or naltrexone (2 mg/kg, i.v.), the noradrenergic alpha2-receptor antagonist idazoxan (10 microg/kg, i.v.), or the serotonin 5-HT(1C/2) receptor antagonist ritanserin (1 or 5 mg/kg b.w., i.p.), did not alter delta9-THC-induced inhibition of pulsatile LH secretion. Pretreatment with a relatively high dose of the beta-adrenergic receptor blocker propranolol (6 mg/kg, i.v.) attenuated the ability of the low THC dose to inhibit LH release; however, lower doses of propranolol were without effect. Furthermore, the ability of a relatively nonspecific serotonin 5-HT(1A/1B) receptor antagonist pindolol (4 mg/kg, s.c.) or the specific 5-HT1A receptor antagonist WAY-100635 (1 mg/kg, s.c.) to significantly attenuate THC-induced LH suppression indicates that activation of serotonergic 5-HT1A receptors may be an important mode by which THC causes inhibition of LH release in the ovariectomized rat.

The roles of nitric oxide (NO) and nitric oxide synthase (NOS) in reproduction were studied by examining the estrous cycle of wild-type (WT) mice, inducible NOS (iNOS)-, and endothelial NOS (eNOS)-knockout mice. We observed an average estrous cycle of 4.8 +/- 0.2 days in WT mice. While we observed no significant influence of iNOS deficiency on cycle length, eNOS-knockout females showed a significantly longer estrous cycle (6.6 +/- 0.6 days; p < 0.03) than WT females, due to an extension of diestrus (p < 0.03). There was no influence of iNOS deficiency on ovulation rate compared with that in WT females; however, eNOS-knockout mice showed a significant reduction (p < 0.05) in ovulatory efficiency relative to WT or iNOS-knockout females. In contrast to WT females, in which the highest level of estradiol (E2) was observed at 1500 h of proestrus, iNOS-knockout females reached a peak of E2 at 1830 h of proestrus. In eNOS-knockout females, the peak of E2 occurred at 1830 h, as in iNOS-knockout mice; however, E2 levels were 5-fold and 3-fold higher (p < 0.05) than levels observed in WT and iNOS-knockout females, respectively. There was no effect of genotype on the plasma LH concentrations at proestrus. On the first day of diestrus, eNOS-knockout females showed significantly higher plasma E2 and progesterone levels (p < 0.05) relative to WT and iNOS-knockout females. The dysfunction in cyclicity, ovulation rate, ovarian morphology, and steroidogenesis in eNOS-knockout female mice strongly supports the concept that eNOS/NO plays critical roles in ovulation and follicular development.

Human endothelial cells (EC) express MHC class II molecules in vivo and are likely to be involved in presentation of antigens to CD4(+) T cells. We examined, at the single-cell level, EC presentation of superantigens to resting CD4(+) memory T cells. Within 2 h of adherence to class II+ EC early T cell activation is evidenced by translocation of nuclear factor of activated T cells (NFAT), surface expression of CD69, and synthesis of IFN-gamma and IL-2. Naive T cells are not activated. T cell activation is dependent on the prior induction of MHC class II molecules on EC and is blocked by antibodies to LFA-3 (CD58). Our data place EC along a spectrum of antigen-presenting ability. Activated B cells and macrophages trigger more cells to express cytokines than do EC and at lower antigen concentrations; EC are in turn, superior to fibroblasts or smooth muscle cells. Furthermore, the concept of activation thresholds for cytokine synthesis within T cells also extends to earlier activation events: NFAT translocation is relatively easy to trigger, as is CD69 expression; fewer cells can be triggered to express IFN-gamma and fewer still to express IL-2. EC may, therefore, contribute to a graded immune response by inducing qualitatively and quantitatively different responses than professional APC., (Copyright 1999 Academic Press.)

Marijuana and its cannabinoid constituents have profound effects on anterior pituitary hormone secretion. Exposure to delta 9-tetrahydrocannabinol inhibits gonadotropin, prolactin, growth hormone, and thyroid-stimulating hormone release and stimulates the release of corticotropin. Consequently, cannabinoid exposure could have profound effects on the function of the reproductive system, lactation, metabolism, and on the endocrine stress axis. The acute effects of cannabinoids on the endocrine system are consistent with its actions on brain neurotransmitter systems involved in the regulation of neuropeptides that modulate anterior pituitary hormone secretion. Although cannabinoid receptors appear to play a major role in the ability of cannabinoids to influence hormone release, much remains to be learned concerning their function in the neuroendocrine regulation of hormone secretion.

The effects of American ginseng (Panax quinquefolium) on male rat copulatory behavior were investigated. Adult Sprague-Dawley rats were administered either 10, 50 or 100 mg/kg of Panax quinquefolium or a sesame oil vehicle per os (p.o.) for 28 days and copulatory behavior parameters were measured. Ginseng-treated male rats demonstrated a significant decrease in mount, intromission and ejaculation latencies compared to vehicle controls. Hormone analyses revealed no difference in plasma luteinizing hormone or testosterone levels between ginseng- and vehicle-treated animals; however, plasma prolactin levels were significantly reduced by all doses of ginseng tested. When male rats were treated with the 100 mg/kg dose of ginseng for 1, 14 or 28 days, mount and intromission latencies were significantly reduced at 14 and 28 days of daily ginseng treatment, whereas ejaculation latency was significantly reduced after 1 day of ginseng treatment when compared to vehicle controls. Plasma prolactin levels were also significantly decreased after 14 and 28 days of daily ginseng administration. There were no differences in body weight or in testes, seminal vesicle, anterior pituitary or spleen weights between ginseng- and vehicle-treated rats. These results demonstrate that P. quinquefolium significantly facilitates male copulatory behavior. The reduction in plasma prolactin levels suggests that ginseng-induced alterations in dopaminergic neurotransmission may play a role in the ability of P. quinquefolium to stimulate copulatory behavior in the male rat.

The ability of cannabinoids to affect anterior pituitary luteinizing hormone (LH) secretion has been largely attributed to a central nervous system site of action, however, the mechanism(s) by which cannabinoids alter LH release remains unclear. In the present study, the acute administration of delta-9-tetrahydrocannabinol (THC) produced a dose-related suppression of plasma LH and stimulation of adrenocorticotropin (ACTH) levels in ovariectomized female rats. To determine if activation of the hypothalamic-pituitary-adrenal axis was involved in the ability of THC to inhibit LH release, female rats were either pretreated with the corticotropin-releasing hormone (CRH) receptor antagonist, alpha-helical CRH, or were adrenalectomized prior to acute THC administration, in order to assess the roles of CRH and corticosterone in the ability of THC to suppress LH secretion. A low dose of THC (0.5 mg/kg b.w., iv) produced a decrease in plasma LH levels at 20 and 40 min posttreatment in ovariectomized, sham adrenalectomized rats. However, in adrenalectomized animals, plasma LH levels were suppressed at 40 min and remained decreased at 80 min following THC administration. Thus, the duration of LH suppression following THC treatment was significantly increased in adrenalectomized versus sham adrenalectomized rats (p < 0.05). Furthermore, pretreatment with the CRH receptor antagonist, alpha-helical CRH (100 micrograms/5 microliters, icv), 30 min before THC administration, attenuated the ability of a high THC dose (1.0 mg/kg) to inhibit LH release in ovariectomized rats. Together, these results demonstrate that THC has significant effects on LH and ACTH secretion in ovariectomized rats and suggest that THC-induced CRH activation, but not corticosterone release, plays a role in the suppression of LH release by cannabinoids.

The effects of prenatal THC administration, given during the third week of gestation in rats, on the reproductive, endocrine and immune systems of the adult offspring were examined. THC treatment blocked the surge of testosterone which occurs in the male rat fetus on gestation day 18. Moreover, when copulatory parameters were measured in adult male offspring, males that had been exposed to THCin utero exhibited an increased latency to mount (THC: 245±49vs vehicle: 99±12 sec) and none of the males ejaculated. Female rats exposed to THCin utero, exhibited an increased incidence of irregular estrous cycles and the number of females exhibiting lordosis behavior was reduced when compared to vehicle controls. Hormone analyses revealed that prolactin levels were significantly lower in the THC-vs vehicle-exposed male (THC: 5.2±0.4vs vehicle: 8.4±0.6 ng/ml) and female offspring (THC: 5.7±0.3vs vehicle: 12.2±1.8 ng/ml). However, there were no significant differences in basal plasma LH levels or in testicular weights of the male offspring. Thymus weight and total number of thymocytes were significantly higher in THC-exposed male and female rats when compared to vehicle controls. Together, these results indicate that maternal THC exposure has long-lasting effects on reproductive, endocrine and immune parameters of both male and female rat offspring.

Male rats exposed to sexually receptive females, exhibit a rapid increase in plasma levels of luteinizing hormone (LH) and prolactin, and concomitant increases in noradrenergic activity in the medial basal hypothalamus (MBH) and median eminence (ME) as well as in dopaminergic activity in the MBH. Delta-9-tetrahydrocannabinol (THC; 5 mg/kg b.wt., PO), the chief psychoactive constituent of marijuana, blocked the MBH and ME noradrenergic response and the dopaminergic response in the MBH in male rats exposed for 20 min to sexually receptive females, and suppressed the expected increases in plasma LH and prolactin levels. Moreover, THC treatment decreased the percentage of animals exhibiting copulatory behavior and increased the latency periods to mount and intromit. These findings indicate that THC interferes with the neuroendocrine and behavioral responses of male rats to the presence of a receptive female.

We have examined the effects of psychoactive and non-psychoactive cannabinoids on isolated immature rat Sertoli cells cultured in either serum-free or serum-containing media. Lactate accumulation by Sertoli cells in serum-free control cultures was 10 fold greater than the values obtained in control cultures exposed to serum. Under either culture condition, 3.1 micrograms/ml of delta-9-tetrahydrocannabinol (THC) or cannabinol (CBN) stimulated lactate secretion above control levels. Cannabidiol (CBD) stimulated lactate secretion in serum-containing but not in serum-free media. Using serum-free culture conditions, we next studied the in vitro effects of combinations of THC and either epinephrine or FSH on lactate and transferrin secretion by immature rat Sertoli cells. Co-incubation of 0.1 microM epinephrine with 0.8 or 3.1 microgram/ml THC significantly stimulated lactate secretion when compared to epinephrine or THC alone, while only the high THC dose increased transferrin secretion. Moreover, co-incubation of FSH (1 micrograms/ml) with THC (0.8 or 3.1 micrograms/ml), significantly stimulated both lactate and transferrin production by immature rat Sertoli cells. These results add to the growing evidence that cannabinoids can exert direct effects on Sertoli cell function and modulate their responses to physiological stimuli.

Despite the extensive use of lithotripsy for treating renal and biliary calculi, there has been little data reported regarding the causes and manifestations of lithotripter failure. The clinical and service records for 145 consecutive treatments performed with the Siemens Lithostar Plus were reviewed. Service record analysis revealed eight failures of shock wave generation during a 10-month period. Six of these failures were subtle and still allowed shock wave generation. There were five in-line ultrasound probe failures during this period. The most useful clinical parameter for predicting lithotripter failure was reduced severity of sonographically evident cavitation bubbles during treatment. Lack of stone fragmentation and unexpectedly low analgesia requirements at high-power levels were less useful in predicting lithotripter failure. All clinical parameters suffered from nonspecificity. Preliminary experience, with an ongoing quality assurance program using a test object hydrophone, suggests this is a useful method of predicting lithotripter function and avoiding compromised treatments.

In this work, we examined the acute effects of two doses of delta-9-tetrahydrocannabinol (THC) on several pre- and postsynaptic biochemical measures of dopaminergic activity in the striatum, limbic forebrain, and hypothalamic-anterior pituitary area of adult male rats. The exposure to a low dose of THC (0.5 mg/kg bw) decreased the number of striatal D2 dopaminergic binding sites, but did not affect their affinity. Treatment with a higher dose of THC was ineffective. In addition, both doses decreased the number of D1 dopaminergic binding sites in the limbic forebrain without changing their affinity. We did not find any changes in the dopamine (DA) or L-3,4-dihydroxyphenylacetic acid (DOPAC) content, or in the DOPAC/DA ratio, in either the striatum or limbic forebrain. THC treatment produced a dose-related decline in plasma prolactin (PRL) levels. Furthermore, both the basal and DA-inhibited in vitro release of PRL were reduced in animals exposed to THC in a dose-dependent manner. This inhibitory effect of THC on PRL release was accompanied by a decreased DOPAC/DA ratio in medial basal hypothalamus that, in turn, may be a result of the fall in PRL levels rather than a direct action of the drug. These data show that acute exposure to THC can alter brain dopaminergic neurotransmission. Our results suggest that the reduction of PRL release following THC exposure, both in vivo and in vitro, might be elicited by a direct action of THC on the pituitary.

The effects of delta-9-tetrahydrocannabinol (THC), alone and in the presence of estradiol (E), on several estrogen-sensitive parameters in the immature female rat were examined, and it was demonstrated that THC administration antagonized the stimulatory effects of E on anterior pituitary weight and on both the secretion and pituitary content of prolactin. In the current study, the anterior pituitary gland was examined as a potential site of THC action in the ability of this cannabinoid to antagonize E-induced stimulation of pituitary function. A stimulatory dose of E (1 nM) significantly elevated prolactin levels in pituitary cells derived from either immature or retired breeder animals. Whereas THC (1 microM) alone had no effect on prolactin levels when compared to controls, THC completely prevented the E-induced increase in media prolactin levels. Moreover, THC blocked the ability of E to desensitize pituitary cells to the inhibitory influence of dopamine. Together with the findings that THC inhibited E-induced stimulation of total RNA synthesis in pituitary cell cultures, these data strongly suggest that THC antagonizes the stimulatory effect of E on the pituitary by a direct action at the adenohypophyseal level.

It has long been recognized that cannabinoids, including delta 9-tetrahydrocannabinol (THC), the major psychoactive substance of marijuana, bear structural similarities to steroid hormones. The hippocampal region of the brain is particularly rich in glucocorticoid receptors (GCRs), and the region also displays dense autoradiographic binding by synthetic cannabinoids. The present report summarizes studies conducted on cannabinoid interaction with hippocampal GCRs, both in vivo and in vitro. Young rats treated for 8 months with THC displayed anatomic and cellular changes in the hippocampus similar to those seen in older, untreated rats, or in rats treated with high levels of glucocorticoids. Binding of [3H]dexamethasone in cytosol prepared from adrenalectomized rat hippocampus was reduced in the presence of 100-fold molar excess of unlabeled THC. However, further increases of THC concentration, to 20,000-fold excess, could displace no more than 50% of radiolabeled dexamethasone. Scatchard analysis of the binding produced a parallel competition plot for THC, versus the plot for dexamethasone, which may reflect a noncompetitive or allosteric interaction with hippocampal GCR. Cannabidiol, a nonpsychoactive cannabinoid, displayed less competition than THC in all parameters. Treatment of adrenalectomized rats for 14 days with 10 mg/kg THC produced down-regulation of hippocampal GCR binding in a manner also reported following high glucocorticoid administration. Although an initial oral administration of THC to intact rats stimulated release of plasma corticosterone, daily repetition of treatment for 7 and 14 days failed to elicit further corticosterone secretion. Taken together, the results indicate that THC may possess some agonist-like properties of glucocorticoids at the hippocampal GCR site.(ABSTRACT TRUNCATED AT 250 WORDS)

The potential estrogenicity or antiestrogenicity of delta 9-tetrahydrocannabinol (THC), the chief psychoactive constituent of marijuana, was evaluated in immature female rats treated for 3 days with estradiol (E2; 1 microgram/kg), THC (10 mg/kg body weight), or E2 + THC. Estradiol treatment significantly increased anterior pituitary, uterine, and oviduct weights. When THC was administered with E2, it prevented the E2-induced increase in pituitary weight, but had no effect on either the uterine or oviduct weight response to E2. In the E2 treatment group, basal prolactin levels were increased and a prolactin surge occurred on the afternoon of the 26th day of age. However, E2-stimulated basal and surge levels of prolactin were significantly attenuated by concomitant THC treatment. Moreover, pituitary prolactin concentrations, which were elevated in E2-treated rats, did not differ from control values in E2 + THC-treated animals. The E2-induced decrease in dopamine turnover rates in the medial basal hypothalamus and increase in the number of anterior pituitary dopamine D2-binding sites (Bmax) were not affected by concomitant THC treatment. Thus, THC antagonizes E2 action on the anterior pituitary via yet to be elucidated mechanism(s).

The acute effects of low oral doses of delta 9-tetrahydrocannabinol (THC), cannabinol (CBN) and cannabidiol (CBD) administered alone or in combinations on LH and prolactin (PRL) secretion and on hypothalamic norepinephrine (NE), dopamine (DA) and serotonin (5-HT) dynamics were examined in adult male rats. Plasma LH levels were significantly reduced 60 min after administration of 0.5 mg THC/kg body weight and 30, 60 and 120 min after administration of THC + CBN or THC + CBD. There were no changes in plasma PRL in response to cannabinoid treatments. The turnover of NE in both the median eminence (ME) and medial basal hypothalamus (MBH) was dramatically affected by all the cannabinoid treatments. Complete suppression of NE turnover occurred 30 min post-THC and 120 min post-THC + CBN in the ME and 120 min post-THC + CBD in the MBH. Cannabinoids did not significantly affect DA turnover in the MBH or the content of NE, DA, 5-HT or 5-hydroxyindole-3-acetic acid in either the ME or MBH. These data demonstrate that treatment of adult male rats with a low dose of THC suppresses LH secretion and that CBN and CBD potentiate this action of THC. Although the mechanisms responsible for the inhibition of LH release by cannabinoids cannot be positively identified from these experiments, the results suggest that alterations in hypothalamic noradrenergic activity may be involved in this effect.

The acute dose-response effects of delta-9-tetrahydrocannabinol (THC), cannabinol (CBN) and cannabidiol (CBD) on gonadotropin and testosterone (T) secretion and on hypothalamic norepinephrine (NE) metabolism were tested in adult male rats. THC and CBN both produced an acute suppression of plasma-luteinizing hormone (LH) and T levels and median eminence NE turnover although a dose-response relationship could not be demonstrated. CBD had no significant effect on any of these parameters and none of these cannabinoids had any effect on plasma follicle-stimulating hormone levels or median eminence LH-releasing hormone (LHRH) content. Except for the highest dose of CBN, none of the in vivo cannabinoid treatments significantly altered in vitro LH secretion although there was a trend towards decreased LH secretion. These results suggest that the decrease in LH secretion in THC- or CBN-treated rats is due to reductions in NE stimulation of LHRH release rather than to changes in LHRH synthesis or pituitary LHRH response.

This study investigated the role of 3 alpha-hydroxy-5 alpha-pregnan-20-one (3 alpha,5 alpha-THP) in the modulation of gonadotropin secretion using the immature ovariectomized (OVX) rat primed with a low dose of estradiol. A treatment regimen of either 0.2 or 0.4 mg/kg of 3 alpha,5 alpha-THP given in conjunction with estradiol for 4 days significantly increased levels of serum luteinizing hormone (LH) but had no effect on serum follicle-stimulating hormone (FSH). Estrogen-primed rats receiving a single injection of 3 alpha,5 alpha-THP at 0930 h showed an increase in serum and pituitary LH levels at 1200 h and 1500 h. At 1800 h, only pituitary levels of LH remained significantly higher than controls. An injection of 3 alpha,5 alpha-THP at 1230 h in estrogen-primed rats resulted in enhanced levels of pituitary LH at 1500 h and elevated levels of both serum and pituitary LH at 1800 h. When 3 alpha,5 alpha-THP was given at 0930 h and 1230 h, elevated serum levels of LH were maintained for over 6 h. The administration of pentobarbital (Pb) 30 min after an injection of 3 alpha,5 alpha-THP at 0930 h or 1230 h prevented the increases in serum LH at 1200 h, 1500 h or 1800 h. This suggests that LH-releasing hormone (LHRH) is involved in mediating the LH response by 3 alpha,5 alpha-THP. There was no change in the sensitivity of the pituitary to LHRH following 3 alpha,5 alpha-THP treatment, indicating the absence of a pituitary effect of this steroid.

The predominant psychoactive constituent of marijuana, delta 9-tetrahydrocannabinol (THC), blocks the preovulatory luteinizing hormone (LH) surge and ovulation in rats treated with THC (10 mg/kg body weight) during the early afternoon of proestrus. When THC-blocked proestrous rats were subjected to unilateral electrochemical stimulation (100 microA anodal DC for 45 s) in the medial preoptic area (mPOA), serum LH was significantly elevated at 30, 60 and 90 min after stimulation in comparison with LH levels measured in sham-stimulated control animals at those times. The induced LH release was sufficient to elicit ovulatory responses comparable to the spontaneous ovulations observed in control rats treated only with the drug vehicle. These results are consistent with the hypothesis that THC inhibits gonadotropin secretion by action within the central nervous system, but demonstrate that the central inhibitory effect of THC does not prevent the release of LH-releasing hormone (LHRH) when the LHRH neurosecretory units are activated by brain stimulation. Thus, the antiovulatory effect of THC appears to result from an inhibition of LH secretion which does not involve the direct blockade of LHRH release.

The purposes, implications, and history of development of the American College of Radiology-National Electrical Manufacturers Association (ACR-NEMA) Digital Imaging and Communication Standard and its contents are briefly described, and the minimum requirements of the ACR-NEMA Digital Imaging and Communication Standard are described with a concise introduction of each layer. The usefulness, validity, current status, and future development of the standard are also discussed.

The effect of 5 alpha-dihydroprogesterone (5 alpha-DHP) on gonadotropin release was examined in the immature acutely ovariectomized (OVX) rat primed with a low dose of estradiol (E2). Treatment with various doses of 5 alpha-DHP given in combination with E2 increased levels of follicle-stimulating hormone (FSH) but had no effect on serum luteinizing hormone (LH). A single injection of a maximally stimulating dose of 5 alpha-DHP (0.4 mg/kg) stimulated increases in serum FSH at 1200 h and, 6 h later, at 1800 h. Pituitary LH and FSH content was dramatically enhanced by 1600 h and levels remained elevated at 1800 h. The administration of pentobarbital at 1200 h, versus 1400 h or 1600 h, prevented the increase in basal serum FSH levels at 1800 h, implying that the release of hypothalamic LH releasing hormone (LHRH) is modulated by 5 alpha-DHP. In addition, changes in pituitary sensitivity to LHRH as a result of 5 alpha-DHP were measured and a significant increase in the magnitude of FSH release was observed at 1200 h and 1800 h. Although the LH response to LHRH in 5 alpha-DHP-treated rats was not different from controls, the duration of LH release was lengthened. These results suggest that 5 alpha-DHP may stimulate FSH release by a direct action at the pituitary level. Together, these observations support the theory that 5 alpha-DHP mediates the facilitative effect of progesterone on FSH secretion and further suggests an action of 5 alpha-DHP in this phenomenon at both pituitary and hypothalamic sites.

The effect of delta 9-tetrahydrocannabinol (THC) on suckling-induced oxytocin release was investigated by recording intramammary pressure changes in suckled rats treated iv with THC (0.5 mg/kg BW) or vehicle. Latency to the first posttreatment milk ejection and posttreatment milk ejection intervals and pressure wave amplitudes were compared between THC- and vehicle-treated rats. Before treatment, intervals between milk ejections averaged 6.5 +/- 1.3 (+/- SE) and 7.0 +/- 0.7 min for vehicle- and THC-treated groups, respectively. Vehicle injections did not alter the frequency of milk ejections, which continued at an overall mean interval of 7.6 +/- 0.7 min after treatment. In contrast, THC treatment was followed by a transient suspension of milk ejections, with a latency of 59.3 +/- 7.4 min before the first posttreatment milk ejection was recorded (P less than 0.001). Intervals between subsequent ejections averaged 15.3 +/- 2.0 to 16.1 +/- 1.3 min and were lengthened relative to corresponding intervals in vehicle-treated animals (P less than 0.05). The amplitudes of pressure waves were not significantly affected by treatment. Oxytocin (0.5 mU) injections 10 or 30 min after THC treatment evoked abrupt increases in intramammary pressure, indicating continued responsiveness of the mammary gland to oxytocin stimulation. These data suggest that THC interferes with the release of oxytocin in response to suckling. To our knowledge, this provides the first evidence that THC inhibits posterior pituitary function.

The effects of 5 alpha-dihydroprogesterone (5 alpha-DHP) and 3 alpha, 5 alpha-tetrahydroprogesterone (3 alpha, 5 alpha-THP) on follicle-stimulating hormone (FSH) and luteinizing hormone (LH) release were examined in the pregnant mare's serum gonadotropin (PMSG)-primed immature female rat (8 IU PMSG at 28 days of age) maintained in constant light. Control rats kept in 14L:10D conditions exhibited proestrous-like surges of LH and FSH release with peak levels attained at 1800 h on the second day after PMSG treatment. In rats exposed to constant light, the PMSG-induced surges of LH and FSH were not only delayed until 1000 h on the third day after PMSG, resulting in a delay in ovulation, but were also significantly attenuated when compared to the gonadotropin surges that occurred on Day 2 in rats kept under normal light-dark conditions. The administration of 5 alpha-DHP significantly enhanced the release of FSH at 1000 h on Day 3 when compared to constant light-exposed controls, but had no effect on LH. Treatment with 3 alpha, 5 alpha-THP selectively potentiated the release of LH at 1000 h on Day 3 and had an attenuating effect on FSH release on Days 2 and 3. These observations confirm earlier findings in the immature ovariectomized estrogen-primed rat and suggest that 5 alpha-DHP and 3 alpha, 5 alpha-THP may have significant roles in the regulation of FSH and LH secretion.