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A defining characteristic of individuals diagnosed with alcohol use disorder (AUD) is that negative outcomes related to drinking do not lead them to reduce their alcohol use. In rodent models of AUD, this characteristic has been studied by adding the bitter tastant quinine to an ethanol solution. In this study, we extended this approach to a nonhuman primate model in which the ability of quinine to decrease the choice of a 4% ethanol solution vs. water was measured. Five adult female rhesus monkeys with 7.3 years of experience drinking ethanol were given access to a 4% ethanol solution and water for 3 h per day. When ethanol choice was stable, a single quinine concentration (0.03-5.6 g /L) was added to the ethanol solution for 1 day until a quinine concentration-effect curve was generated. After determining the quinine concentration that reduced ethanol choice by half (the quinine EC 50 ), the relative reinforcing strength of ethanol was manipulated by adding quinine or sucrose to the water alternative depending on the monkey's baseline choice. Adding quinine to ethanol produced a concentration-dependent decrease in ethanol choice and intake. Importantly, water intake increased, indicating an effect on response allocation rather than simply a decrease in fluid consumption. Consistent with this conclusion, the addition of quinine or sucrose to the water alternative resulted in predictable increases and decreases, respectively, in ethanol choice. These studies establish a model of punishment of ethanol choice in nonhuman primates that can be used to understand the contextual, biologic and pharmacologic factors that influence sensitivity to the punishment of alcohol drinking.

Nonhuman primate models of alcohol use disorder (AUD) frequently utilize schedule-induced polydipsia to initiate ethanol drinking. Previous research has demonstrated that specific characteristics of drinking during the final phase of induction, in which monkeys consume 1.5 g/kg of ethanol per day, can predict whether monkeys become heavy or light drinkers when they subsequently have free access to ethanol (22 hours per day; Baker, Farro, Gonzales, Helms, & Grant, 2017; Grant et al., 2008). A monkey's position in the social dominance hierarchy is another factor associated with ethanol drinking in nonhuman primates; lower social status is associated with higher ethanol intakes. In the present study, characteristics of drinking during induction were measured in 12 male cynomolgus monkeys living in three established social groups (4 monkeys per group). All monkeys were induced to consume water, then increasing doses of ethanol (0.5, 1.0, and 1.5 g/kg) for 30 sessions per dose using a 300-s fixed-time schedule of food pellet delivery. Drinking sessions occurred five days per week and monkeys were group-housed on the other two days. Contrary to our hypothesis that subordinate monkeys would show characteristics of drinking during the last phase of induction that were predictive of later heavy drinking, no significant differences were observed between dominant and subordinate monkeys in any phase of induction. When ethanol availability was subsequently increased to 22 hours per day for 5 weeks, the intakes of subordinate- and dominant-ranked monkeys diverged, with higher intakes on average in subordinates. Several factors unique to the conditions of induction may have obscured any influence of social rank, including the limited duration of sessions and limited maximal ethanol intake. The data support the conclusion that the effects of social rank on ethanol consumption require unrestricted access to ethanol.

GluN2B subunit-containing N-methyl-d-aspartate (NMDA) receptors have been implicated in various neurological disorders. Nonetheless, a validated fluorine-18 labeled positron emission tomography (PET) ligand for GluN2B imaging in the living human brain is currently lacking. As part of our PET ligand development program, we have recently reported on the preclinical evaluation of [18F]OF-NB1 – a GluN2B PET ligand with promising attributes for potential clinical translation. However, the further development of [18F]OF-NB1 is currently precluded by major limitations in the radiolabeling procedure. These limitations include the use of highly corrosive reactants and racemization during the radiosynthesis. As such, the aim of this study was to develop a synthetic approach that allows an enantiomerically pure radiosynthesis of (R)-[18F]OF-NB1 and (S)-[18F]OF-NB1, as well as to assess their in vitro and in vivo performance characteristics for imaging the GluN2B subunit-containing NMDA receptor in rodents. A two-step radiosynthesis involving radiofluorination of the boronic acid pinacol ester, followed by coupling to the 3-benzazepine core structure via reductive amination was employed. The new synthetic approach yielded enantiomerically pure (R)-[18F]OF-NB1 and (S)-[18F]OF-NB1, while concurrently circumventing the use of corrosive reactants. In vitro autoradiograms with mouse and rat brain sections revealed a higher selectivity of (R)-[18F]OF-NB1 over (S)-[18F]OF-NB1 for GluN2B-rich brain regions. In concert with these observations, blockade studies with commercially available GluN2B antagonist, CP101606, showed a significant signal reduction, which was more pronounced for (R)-[18F]OF-NB1 than for (S)-[18F]OF-NB1. Conversely, blockade experiments with sigma2 ligand, FA10, did not result in a significant reduction of tracer binding for both enantiomers. PET imaging experiments with CD1 mice revealed a higher brain uptake and retention for (R)-[18F]OF-NB1, as assessed by visual inspection and volumes of distribution from Logan graphical analyses. In vivo blocking experiments with sigma2 ligand, FA10, did not result in a significant reduction of the brain signal for both enantiomers, thus corroborating the selectivity over sigma2 receptors. In conclusion, we have developed a novel synthetic approach that is suitable for upscale to human use and allows the enantiomerically pure radiosynthesis of (R)-[18F]OF-NB1 and (S)-[18F]OF-NB1. While both enantiomers were selective over sigma2 receptors in vitro and in vivo, (R)-[18F]OF-NB1 showed superior GluN2B subunit specificity by in vitro autoradiography and higher volumes of distribution in small animal PET studies.

Alterations in brain cholesterol homeostasis have been broadly implicated in neurological disorders. Notwithstanding the complexity by which cholesterol biology is governed in the mammalian brain, excess neuronal cholesterol is primarily eliminated by metabolic clearance via cytochrome P450 46A1 (CYP46A1). No methods are currently available for visualizing cholesterol metabolism in the living human brain; therefore, a noninvasive technology that quantitatively measures the extent of brain cholesterol metabolism via CYP46A1 could broadly affect disease diagnosis and treatment options using targeted therapies. Here, we describe the development and testing of a CYP46A1-targeted positron emission tomography (PET) tracer, 18 F-CHL-2205 ( 18 F-Cholestify). Our data show that PET imaging readouts correlate with CYP46A1 protein expression and with the extent to which cholesterol is metabolized in the brain, as assessed by cross-species postmortem analyses of specimens from rodents, nonhuman primates, and humans. Proof of concept of in vivo efficacy is provided in the well-established 3xTg-AD murine model of Alzheimer’s disease (AD), where we show that the probe is sensitive to differences in brain cholesterol metabolism between 3xTg-AD mice and control animals. Furthermore, our clinical observations point toward a considerably higher baseline brain cholesterol clearance via CYP46A1 in women, as compared to age-matched men. These findings illustrate the vast potential of assessing brain cholesterol metabolism using PET and establish PET as a sensitive tool for noninvasive assessment of brain cholesterol homeostasis in the clinic.

GluN2B is the most studied subunit of N-methyl-D-aspartate receptors (NMDARs) and implicated in the pathologies of various central nervous system disorders and neurodegenerative diseases. As pan NMDAR antagonists often produce debilitating side effects, new approaches in drug discovery have shifted to subtype-selective NMDAR modulators, especially GluN2B-selective antagonists. While positron emission tomography (PET) studies of GluN2B-selective NMDARs in the living brain would enable target engagement in drug development and improve our understanding in the NMDAR signaling pathways between normal and disease conditions, a suitable PET ligand is yet to be identified. Herein we developed an (18)F-labeled potent antagonist, 2-((1-(4-[(18)F]fluoro-3-methylphenyl)-1H-1,2,3-triazol-4-yl)methoxy)-5-methoxypyrimidine ([(18)F]13; also called [(18)F]N2B-0518) as a PET tracer for imaging the GluN2B subunit. The radiofluorination of [(18)F]13 was efficiently achieved by our spirocyclic iodonium ylide (SCIDY) method. In in vitro autoradiography studies, [(18)F]13 displayed highly region-specific binding in brain sections of rat and non-human primate, which was in accordance with the expression of GluN2B subunit. Ex vivo biodistribution in mice revealed that [(18)F]13 could penetrate the blood-brain barrier with moderate brain uptake (3.60% ID/g at 2 min) and rapid washout. Altogether, this work provides a GluN2B-selective PET tracer bearing new chemical scaffold and shows high specificity to GluN2B subunit in vitro, which may pave the way for the development of a new generation of GluN2B PET ligands.

Background Although most individuals with cocaine use disorder also abuse alcohol, little is known about the behavioral and pharmacological mechanisms that promote co-abuse. For example, it is unclear whether prior experience with alcohol renders individuals more sensitive to cocaine when it is subsequently experienced. Methods This study examined the effects of chronic ethanol consumption on subsequent cocaine reinforcement in rhesus monkeys. Six monkeys consumed 2.0 g/kg ethanol in a binge-drinking paradigm and 6 monkeys drank a non-alcoholic solution 5 days per week. After 9 months, each monkey’s sensitivity to acquiring cocaine self-administration was determined. Monkeys performed an operant response resulting in food pellet delivery under a fixed-ratio 30 schedule of reinforcement. Saline, then ascending doses of cocaine, were substituted for food pellets until a cocaine dose was reached at which the number of cocaine injections delivered differed significantly from saline injections delivered. Following acquisition, a complete cocaine dose-effect curve was generated to determine whether ethanol consumption altered the reinforcing potency of cocaine determined by calculating the ED50 of the ascending limb of each subject’s curve. Results Although individual variability was observed, the cocaine dose which initially served as a reinforcer did not differ between ethanol-drinking and control groups and, within the ethanol-drinking group, was not related to the amount of ethanol consumed. Moreover, the reinforcing potency of cocaine did not differ between groups. Conclusion Taken together, the data suggest that a history of binge-like alcohol consumption does not affect sensitivity to cocaine when it is subsequently first experienced.

A fundamental question for alcohol use disorder is how naïve brain networks are reorganized in response to the consumption of alcohol. The current study aimed to determine the progression of alcohol’s effect on functional brain networks during the transition from naïve, to early, to chronic consumption. Resting-state brain networks of six female monkeys were acquired using magnetoencephalography prior to alcohol exposure, after early exposure, and after free-access to alcohol using a well-established model of chronic heavy alcohol use. Functional brain network metrics were derived at each time point. Assortativity, average connection frequency, and number of gamma connections changed significantly over time. All metrics remained relatively stable from naïve to early drinking, and displayed significant changes following increased quantity of alcohol consumption. The assortativity coefficient was significantly less negative (p=.043), connection frequency increased (p=.03), and gamma connections increased (p=.034). Further, brain regions considered hubs (p=.037) and members of the Rich Club (p=.012) became less common across animals following the introduction of alcohol. The minimum degree of the Rich Club prior to alcohol exposure was significantly predictive of future free-access drinking (r=-.88, p

Leucin-rich repeat kinase 2 (LRRK2) is a large protein that is involved in the pathogenesis of Parkinson’s disease (PD). It has been demonstrated that LRRK2 mutations mainly confers PD, which bring about increased kinase activity of LRRK2. As a consequence, selective inhibition of LRRK2 may help to recover the normal functions of LRRK2, and thereafter serve as an alternatively promising therapeutic target for PD treatment. The mapping of LRRK2 with PET studies allows a deep understanding of PD and other LRRK2-related disorders, as well as helps to validate and translate novel LRRK2 inhibitors. However, to date no LRRK2 PET probes have been reported in the primary literature. In this study, we present a facile synthesis and preliminary evaluation of [(11)C]GNE-1023 as a novel potent PET probe for LRRK2 imaging in PD. [(11)C]GNE-1023 was synthesized in good radiochemical yield (10% non-decay corrected RCY), excellent radiochemical purity (>99%) and high molar activity (>37 GBq / μmol). Excellent in vitro binding specificity of [(11)C]GNE-1023 towards LRRK2 was demonstrated in cross species studies, including rat and nonhuman primate brain tissues by autoradiography experiments. Subsequent whole-body biodistribution studies indicated limited brain uptake and urinary and hepatobiliary elimination of this radioligand. This study may pave the way for the further development of a new generation of LRRK2 PET probes.

Alcohol use disorder (AUD) persists as a devastating public health problem; widely effective pharmacological treatments are needed. Evidence from rodent models suggests that stimulating brain receptors for the neuropeptide nociceptin/orphanin FQ (NOP) can decrease ethanol drinking. We characterized the effects of the mu opioid peptide (MOP) receptor agonist buprenorphine and the buprenorphine analog (2S)-2-[(5R,6R,7R,14S)-N-cyclopropylmethyl-4,5-epoxy-6,14-ethano-3-hydroxy-6 methoxymorphinan-7-yl]-3,3-dimethylpentan-2-ol (BU08028), which stimulates MOP and NOP receptors, in a translational nonhuman primate model of AUD. Rhesus monkeys drank a 4% ethanol solution 6 h per day, 5 days per week via an operant behavioral panel in their home cages. To assess behavioral selectivity, monkeys responded via a photo-optic switch to earn food pellets. After characterizing the acute effects of BU08028 (0.001–0.01 mg/kg, i.m.) and buprenorphine (0.003–0.056 mg/kg, i.m.), the drugs were administered chronically using a model of pharmacotherapy assessment that incorporates clinical aspects of AUD and treatment. Acutely, both drugs decreased ethanol drinking at doses that did not affect food-maintained responding. During chronic treatment, effects of BU08028 and buprenorphine were maintained for several weeks without development of tolerance or emergence of adverse effects. BU08028 was ~0.5 and 1.0 log units more potent in acute and chronic studies, respectively. The selective NOP receptor agonist SCH 221510 also selectively decreased ethanol intakes when given acutely (0.03–1.0 mg/kg, i.m.), whereas the MOP antagonist naltrexone (1.7–5.6 mg/kg, i.m.) decreased both ethanol intake and food pellets delivered. These data demonstrate that bifunctional MOP/NOP agonists, which may have therapeutic advantages to MOP-selective drugs, can decrease alcohol drinking in nonhuman primates.

Dysregulation of microtubules is commonly associated with several psychiatric and neurological disorders, including addiction and Alzheimer’s disease. Imaging of microtubules in vivo using positron emission tomography (PET) could provide valuable information on their role in the development of disease pathogenesis and aid in improving therapeutic regimens. We developed [11C]MPC-6827, the first brain-penetrating PET radiotracer to image microtubules in vivo in the mouse brain. The aim of the present study was to assess the reproducibility of [11C]MPC-6827 PET imaging in non-human primate brains. Two dynamic 0–120 min PET/CT imaging scans were performed in each of four healthy male cynomolgus monkeys approximately one week apart. Time activity curves (TACs) and standard uptake values (SUVs) were determined for whole brains and specific regions of the brains and compared between the “test” and “retest” data. [11C]MPC-6827 showed excellent brain uptake with good pharmacokinetics in non-human primate brains, with significant correlation between the test and retest scan data (r = 0.77, p = 0.023). These initial evaluations demonstrate the high translational potential of [11C]MPC-6827 to image microtubules in the brain in vivo in monkey models of neurological and psychiatric diseases.

Chronic alcohol abuse is associated with neurophysiological changes in brain activity; however, these changes are not well localized in humans. Non-human primate models of alcohol abuse enable control over many potential confounding variables associated with human studies. The present study utilized high-resolution magnetoencephalography (MEG) to quantify the effects of chronic EtOH self-administration on resting state (RS) brain function in vervet monkeys.Adolescent male vervet monkeys were trained to self-administer ethanol (n=7) or an isocaloric malto-dextrin solution (n=3). Following training, animals received 12 months of free access to ethanol. Animals then underwent RS magnetoencephalography (MEG) and subsequent power spectral analysis of brain activity at 32 bilateral regions of interest associated with the chronic effects of alcohol use.demonstrate localized changes in brain activity in chronic heavy drinkers, including reduced power in the anterior cingulate cortex, hippocampus, and amygdala as well as increased power in the right medial orbital and parietal areas.The current study is the first demonstration of whole-head MEG acquisition in vervet monkeys. Changes in brain activity were consistent with human electroencephalographic studies; however, MEG was able to extend these findings by localizing the observed changes in power to specific brain regions. These regions are consistent with those previously found to exhibit volume loss following chronic heavy alcohol use. The ability to use MEG to evaluate changes in brain activity following chronic ethanol exposure provides a potentially powerful tool to better understand both the acute and chronic effects of alcohol on brain function.

An estimated 18 million adults in the United States meet the clinical criteria for diagnosis of alcohol abuse or alcoholism, a disorder ranked as the third leading cause of preventable death. In addition to brain pathology, heavy alcohol consumption is comorbid with damage to major organs including heart, lungs, liver, pancreas, and kidneys. Much of what is known about risk for and consequences of heavy consumption derive from rodent or retrospective human studies. The neurobiological effects of chronic intake in rodent studies may not easily translate to humans due to key differences in brain structure and organization between species, including a lack of higher-order cognitive functions, and differences in underlying prefrontal cortical neural structures that characterize the primate brain. Further, rodents do not voluntarily consume large quantities of ethanol (EtOH) and they metabolize it more rapidly than primates.The basis of the Monkey Alcohol Tissue Research Resource (MATRR) is that nonhuman primates, specifically monkeys, show a range of drinking excessive amounts of alcohol (3.0 g/kg or a 12 drink equivalent per day) over long periods of time (12 to 30 months) with concomitant pathological changes in endocrine, hepatic, and central nervous system (CNS) processes. The patterns and range of alcohol intake that monkeys voluntarily consume parallel what is observed in humans with alcohol use disorders and the longitudinal experimental design spans stages of drinking from the EtOH-naïve state to early exposure through chronic abuse. Age- and sex-matched control animals self-administer an isocaloric solution under identical operant procedures.The MATRR is a unique postmortem tissue bank that provides CNS and peripheral tissues, and associated bioinformatics from monkeys that self-administer EtOH using a standardized experimental paradigm to the broader alcohol research community.This resource provides a translational platform from which we can better understand the disease processes associated with alcoholism.

Alcoholism is a disorder categorized by significant impairment that is directly related to persistent and extreme use of alcohol. The effects of alcoholism on c-Myc protein expression in the brain have been scarcely studied. This is the first study to investigate the role different characteristics of alcoholism have on c-Myc protein in the brain. We analyzed c-Myc protein in the hypothalamus and amygdala from five different animal models of alcohol abuse. c-Myc protein was increased following acute ethanol exposure in a mouse knockout model and following chronic ethanol consumption in vervet monkeys. We also observed increases in c-Myc protein exposure in animals that are genetically predisposed to alcohol and methamphetamine abuse. Lastly, c-Myc protein was increased in animals that were acutely exposed to methamphetamine when compared to control treated animals. These results suggest that in substance abuse c-Myc plays an important role in the brain's response.

Background Long-term alcohol abuse is associated with change in behavior, brain structure, and brain function. However, the nature of these changes is not well understood. In this study, we used network science to analyze a nonhuman primate model of ethanol self-administration to evaluate functional differences between animals with chronic alcohol use and animals with no exposure to alcohol. Of particular interest was how chronic alcohol exposure may affect the resting state network. Methods Baseline resting state functional magnetic resonance imaging was acquired in a cohort of vervet monkeys. Animals underwent an induction period where they were exposed to an isocaloric maltose dextrin solution (control) or ethanol in escalating doses over three 30-day epochs. Following induction, animals were given ad libitum access to water and a maltose dextrin solution (control) or water and ethanol for 22 h/d over 12 months. Cross-sectional analyses examined region of interests in hubs and community structure across animals to determine differences between drinking and nondrinking animals after the 12-month free access period. Results Animals were classified as lighter (

Neuroimaging of animal models of alcoholism offers a unique path for translational research to the human condition. Animal models permit manipulation of variables that are uncontrollable in clinical, human investigation. This symposium, which took place at the annual meeting of the Research Society on Alcoholism in Vancouver, British Columbia, Canada, on June 29th, 2004, presented initial findings based on neuroimaging studies from the two centers of the Integrative Neuroscience Initiative on Alcoholism funded by the National Institute on Alcohol Abuse and Alcoholism. Effects of alcohol exposure were assessed with in vitro glucose metabolic imaging of rat brain, in vitro receptor imaging of monkey brain, in vivo magnetic resonance imaging of monkey brain, and in vivo magnetic resonance spectroscopic quantification of alcohol metabolism kinetics in rat brain.

Reproductive function in some nonhuman primate species parallels that of the human. As a result, studies addressing aspects of reproductive function primarily involve the use of nonhuman primate models. The objective of the present study was to assess the efficiency of two hypothalamic down-regulation techniques combined with a single controlled ovarian hyperstimulation protocol for mature oocyte production in the cynomolgus macaque (Macaca fascicularis). Hypothalamic GnRH down regulation was first induced using the clinical long protocol of the short-acting GnRH-agonist luprolide acetate combined with controlled ovarian hyperstimulation and oocyte retrieval. Resulting oocyte yield and maturity with this regimen was insufficient for further evaluation of oocyte competency. Hypothalamic down regulation was induced in the second experiment using the long-acting depot formulation of luprolide acetate in conjunction with controlled ovarian hyperstimulation. This regimen allowed for the consistently efficient production of oocytes (15.5 oocytes per oocyte retrieval) and an oocyte maturity rate of 56%. Oocyte competence, as determined by the ability to undergo fertilization or parthenogenic activation and to reach specific cleavage stages at appropriate time intervals, was evaluated. Intracytoplasmic sperm injection resulted in a 59% fertilization rate and a 91% cleavage rate. Parthenogenic activation resulted in a 70% activation rate and an 86% cleavage rate. These data suggest that use of the long-acting form of luprolide acetate in conjunction with controlled ovarian hyperstimulation results in the production of competent, mature oocytes and allows the efficient use of nonhuman primate resources in studies of reproductive function in cynomolgus macaques.

Objective: Our goal was to examine the variables present at the time of embryo transfer and to determine their effects on the clinical pregnancy rate. Study Design: All fresh and frozen embryo transfers during a 3-year period in a university-based in vitro fertilization program were examined. Female age, previous in vitro fertilization attempt, diagnosis, embryo number and quality, transfer technique, and presence of a clinical pregnancy were recorded for each couple. Logistic regression analyses were performed both univariately and multivariately to determine the association between a clinical pregnancy and the independent variables. Results: All transfers during the study period were included in the analysis. The four primary diagnoses were pelvic or tubal disease, male factor infertility, unexplained infertility, and endometriosis. The 46 frozen embryo transfers had a clinical pregnancy rate similar to that among the 159 fresh embryo transfers and were therefore included in the analysis. One variable was found to significantly affect the outcome, the number of high-grade embryos placed. The presence of a previous failed embryo transfer tended to lower the success rate for future attempts; however, this result did not reach statistical significance. The catheter type and the transfer difficulty did not affect outcome. Conclusion: The two most important variables for predicting a clinical pregnancy are a first-time transfer and the number of high-grade embryos placed. Neither the type of embryo transfer catheter used nor the diagnosis affected outcome. In this small sample difficult embryo transfers did not diminish the chance for a successful outcome. (Am J Obstet Gynecol 2000;182:1001-4.)

Background Chronic alcohol consumption reduces brain serotonin and alters the synaptic mechanisms involved in memory formation. Hippocampal 5-HT 1A receptors modulate these mechanisms, but the neuroadaptive response of 5HT 1A receptors to chronic alcohol self-administration is not well understood. Methods Hippocampal tissue from monkeys that voluntarily self-administered ethanol for 12 months ( n = 9) and accompanying controls ( n = 8) were prepared for in vitro receptor autoradiography and laser capture microdissection. The 5-HT 1A receptor antagonist, [ 3 H]MPPF, and the agonist, [ 3 H]8-OH-DPAT, were used to measure total and G-protein coupled 5-HT 1A receptors respectively. The expression of the genes encoding the 5-HT 1A receptor and its trafficking protein Yif1B was measured in microdissected dentate gyrus (DG) granule cells and CA1 pyramidal neurons. Results An increase in G-protein coupled, but not total, receptors was observed in the posterior pyramidal cell layer of CA1 in ethanol drinkers compared to controls. Chronic ethanol self-administration was also associated with an up-regulation of total and G-protein coupled 5-HT 1A receptors in the posterior DG polymorphic layer. Changes in receptor binding were not associated with concomitant changes in 5-HT 1A receptor mRNA expression. Chronic ethanol self-administration was associated with a significant increase in Yif1B gene expression in posterior CA1 pyramidal neurons. Conclusions Chronic, ethanol self-administration up-regulates hippocampal 5-HT 1A receptor density in a region-specific manner that does not appear to be due to alterations at the level of transcription but instead may be due to increased receptor trafficking. Further exploration of the mechanisms mediating chronic ethanol-induced 5-HT 1A receptor up-regulation and how hippocampal neurotransmission is altered is warranted.

Appropriate animal models are critical to conduct translational studies of human disorders without variables that can confound clinical studies. Such analytic methods as patch-clamp electrophysiological and voltammetric recordings of neurons in brain slices require living brain tissue. In order to obtain viable tissue from nonhuman primate brains, tissue collection methods must be designed to preserve cardiovascular and respiratory functions for as long as possible. This paper describes a method of necropsy that has been used in three species of monkeys that satisfies this requirement. At necropsy, animals were maintained under a deep surgical plane of anesthesia while a craniotomy was conducted to expose the brain. Following the craniotomy, animals were perfused with ice-cold, oxygenated artificial cerebrospinal fluid to displace blood and to reduce the temperature of the entire brain. The brain was removed within minutes of death and specific brain regions were immediately dissected for subsequent in vitro electrophysiology or voltammetry experiments. This necropsy method also provided for the collection of tissue blocks containing all brain regions that were immediately frozen and stored for subsequent genomic, proteomic, autoradiographic and histological studies. An added benefit from the design of this necropsy method is that all major peripheral tissues were also collected and are now being utilized in a wide range of genomic, biochemical and histological assays. This necropsy method has resulted in the establishment and growth of a nonhuman primate alcohol tissue bank designed to distribute central nervous system and peripheral tissues to the larger scientific community.

The hypothesis that endogenous opioids might have a role in mediating the suppressive effects of nicotine on serum LH concentrations in rats was investigated. Naltrexone treatment prevented the inhibitory effect of high doses of nicotine on serum LH concentrations. Nicotine treatment also prevented the stimulatory effect of naltrexone on serum LH concentrations. These results suggest that the inhibitory effects of nicotine on serum LH concentrations involve an opioidergic component.

Numerous biochemical as well as electrophysiological techniques require tissue that must be retrieved very quickly following death in order to preserve the physiological integrity of the neuronal environment. Therefore, the ability to accurately predict the precise locations of brain regions of interest (ROI) and to retrieve those areas as quickly as possible following the brain harvest is critical for subsequent analyses. One way to achieve this objective is the utilization of high resolution MRI scans to guide the subsequent dissections. In the present study, individual MRI scans of the brains of rhesus and cynomolgus macaques that had chronically self-administered ethanol were employed in order to determine which blocks of dissected tissue contained specific ROIs. MRI-guided brain dissection of discrete brain regions was completely accurate in 100% of the cases. In comparison, approximately 60–70% accuracy was achieved in dissections that relied on external landmarks alone without the aid of MRI. These results clearly demonstrate that the accuracy of targeting specific brain areas can be improved with high-resolution MR imaging.

Rats were subjected to right side dorsal rhizotomy of spinal nerves T12-L2 and ipsi- or contralateral unilateral ovariectomy at estrus (day 1). Estrous cycles were recorded daily, and on day 15 the remaining ovary was removed and weighed. Antral follicles were counted in representative day 1 and day 15 ovaries. Dorsal rhizotomy did not affect estrous cycles during the period after surgery. Also dorsal rhizotomy did not alter ipsilateral ovarian hypertrophy or follicular activation following unilateral ovariectomy. Thus, although the major portion of the ovarian sensory innervation is via the lesioned segments, interruption of these segments centrally does not alter compensatory ovarian responses subsequent to unilateral ovariectomy.

The effect of cyclosporin A (CsA) treatment on LH and prolactin was investigated. Chronic daily administration of an immunosuppressive dose of CsA (1.5 mg/100g bw) increased serum LH concentrations and pituitary gland LH content. CsA treatment also resulted in increased serum testosterone. Immunosuppressive doses of CsA had no effect on serum prolactin or pituitary gland prolactin content. Acute administration of low doses of 0.12, 1.2, 12 and 120ug CsA/100g bw had no effect on serum LH or prolactin. These results suggest that administration of immunosuppressive doses of CsA alters serum and pituitary LH and serum testosterone but not prolactin.