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Current strategies to manage preterm labor center around inhibition of uterine myometrial contractions, yet do not improve neonatal outcomes as they do not address activation of inflammation. Here, we identify that during human labor, activated oxytocin receptor (OTR) reprograms the prostaglandin E2 receptor, EP2, in the pregnant myometrium to suppress relaxatory/Gαs-cAMP signaling and promote pro-labor/inflammatory responses via altered coupling of EP2 from Gαq/11 to Gαi/o. The ability of EP2 to signal via Gαi/o is recapitulated with in vitro OT and only following OTR activation, suggesting direct EP2-OTR crosstalk. Super-resolution imaging with computational modeling reveals OT-dependent reorganization of EP2-OTR complexes to favor conformations for Gαi over Gαs activation. A selective EP2 ligand, PGN9856i, activates the relaxatory/Gαs-cAMP pathway but not the pro-labor/inflammatory responses in term-pregnant myometrium, even following OT. Our study reveals a mechanism, and provides a potential therapeutic solution, whereby EP2-OTR functional associations could be exploited to delay preterm labor.

Ambulatory nursing services are essential to healthcare in communities, but nursing curricula often omit ambulatory care training. The purpose of this project was to enhance ambulatory care competencies among nursing students and provide ongoing education for practicing nurses through an academic-practice partnership.A four-year externally funded project targeted enhancements to undergraduate nursing curricula and development activities. Students received didactic content and clinical experiences and were evaluated to assess critical ambulatory care nursing skills. Existing continuing education offerings were enhanced with team-based practice content.Despite pandemic-related clinical training changes, data from multiple quarters showed improvement in students' perceptions of self-efficacy (1.7-4.28-point increases) and actual performance (3.46-4.05-point increases) of core competencies on the 20-point evaluation scales. In addition, students rated simulations favorably, with scores ranging from 1.4 to 1.9 on the 2-point subscales.An academic-practice partnership provides mutually beneficial opportunities for enhancing the ambulatory care nursing workforce through undergraduate education and training and professional development for practicing nurses.

Aim This concept analysis aims to distinguish the concept of nurse empowerment as an individual professional process rather than a job-related process and to identify ways in which a clarified understanding of individual empowerment can impact the discipline. Background The history of nursing as a gendered role has led to oppression in the profession as evidenced by lateral violence and attrition. Empowerment initiatives that focus on a nurse within an organization often provide false power. Design Walker and Avant's method was used for this concept analysis. Data source Published literature from 1990 to 2019 was identified from electronic health profession-related databases, and current definitions and uses of empowerment were pulled from empirical works and electronic databases. Review methods A review of abstracts and full text from articles relating to nurse empowerment was performed, and empirical studies used to provide an understanding of the concept as used today. Results True empowerment entails a nurse controlling her practice and career. Elements of individual empowerment can be pulled from existing work on structural and psychological empowerment. Conclusions Analyzing nurse empowerment from an individual perspective allows us to move beyond the oppressive history of nursing and move the profession forward to impact our communities.

Purpose: Two features define the future of glaucoma therapeutics: (1) greatly improved ocular hypotensive efficacy and (2) a delivery method that improves patient convenience and complianc...

Background and purpose Prostanoid EP2 receptor agonists exhibit several activities including ocular hypotension, tocolysis and anti-inflammatory activity. This report describes the affinity and selectivity of a structurally novel, non-prostanoid EP2 receptor agonist, PGN-9856, and its therapeutic potential. Experimental approach The pharmacology of a series of non-prostanoid EP2 receptor agonists was determined according to functional and radioligand binding studies, mostly using human recombinant prostanoid receptor transfectants. The selectivity of PGN-9856, as the preferred compound, was subsequently determined by using a diverse variety of non-prostanoid target proteins. The therapeutic potential of PGN-9856 was addressed by determining its activity in relevant primate cell, tissue and disease models. Key results PGN-9856 was a selective and high affinity (pKi ≥ 8.3) ligand at human recombinant EP2 receptors. In addition to high affinity binding, it was a potent and full EP2 receptor agonist with a high level of selectivity at EP1 , EP3 , EP4 , DP, FP, IP and TP receptors. In cells overexpressing human recombinant EP2 receptors, PGN-9856 displayed a potency (pEC50 ≥ 8.5) and a maximal response (increase in cAMP) comparable to that of the endogenous agonist PGE2 . PGN-9856 exhibited no appreciable affinity (up 10 μM) for a range of 53 other receptors, ion channels and enzymes. Finally, PGN-9856 exhibited tocolytic, anti-inflammatory and long-acting ocular hypotensive properties consistent with its potent EP2 receptor agonist properties. Conclusions and implications PGN-9856 is a potent, selective and efficacious prostanoid EP2 receptor agonist with diverse potential therapeutic applications: tocolytic, anti-inflammatory and notably anti-glaucoma.

Prostaglandin (PG) E analogs are used clinically to ripen the cervix and induce labor. However, selective receptor agonists may have potential to improve induction response rates or manage unwanted uterine hypercontractility in conditions such as dysmenorrhea and preterm labor. To characterize their therapeutic value, PGE

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The purpose of these studies was (1) to investigate the ability of human M1 phenotype macrophages to secrete vascular endothelial growth factor (VEGF) and the influence of prostacyclin receptor (IP) stimulation (2) to evaluate the contribution of the proangiogenic prostanoid prostacyclin to experimental choroidal neovascularization Methods: Human macrophages derived from primary blood mononuclear cells were functionally biased toward the M1 phenotype by using tumor necrosis factor α (TNFα). Experimental choroidal neovascularization was produced by laser photocoagulation. Antagonist drugs RO-3244794 (IP antagonist) and GW 627368 (EPIP receptor stimulation had diametrically opposed effects on VEGF release compared with reported data on cytokine/chemokine secretion from human macrophages. For example, the IP agonist cicaprost stimulated VEGF secretion although it inhibits monocyte chemoattractant protein-1 (MCP-1) secretion: both would favor a proangiogenic effect. The IP receptor antagonist RO-3244794 produced an ∼20% statistically significant reduction in the neovascularized lesion area in the choroidal neovascularization model, which was a similar level to that produced by the EPIP receptor stimulation potently and highly efficaciously promoted VEGF release from human M1 macrophages, indicating a possible contribution of the M1 macrophage subtype to VEGF-induced choroidal neovascularization. Studies in living animals suggest that prostacyclin and its target IP receptor contribute to choroidal neovascularization, although to a more modest extent than might have been expected.

The naturally occurring mammalian endocannabinoids possess biological attributes that extend beyond interaction with cannabinoid receptors. These extended biological properties are the result of oxidative metabolism of the principal mammalian endocannabinoids arachidonoyl ethanolamide (anandamide; A-EA) and 2-arachidonoylglycerol (2-AG). Both endocannabinoids are oxidized by cyclo-oxygenase-2 (COX-2), but not by COX-1, to a series of prostaglandin derivatives (PGs) with quite different biological properties from those of the parent substrates. PG ethanolamides (prostamides, PG-EAs) and PG glyceryl esters (PG-Gs) are not only pharmacologically distinct from their parent endocannabinoids, they are distinct from the corresponding acidic PGs, and are differentiated from each other. Ethanolamides and glyceryl esters of the major prostanoids PGD2, PGE2, PGF2α, and PGI2 are formed by the various PG synthases, and thromboxane ethanolamides and glyceryl esters are not similarly produced. COX-2 is also of interest by virtue of its corollary central role in modulating endocannabinoid tone, providing a new therapeutic approach for treating pain and anxiety. Other major oxidative conversion pathways are provided for both A-EA and 2-AG by several lipoxygenases (LOXs), resulting in the formation of numerous hydroxyl metabolites. These do not necessarily represent inactivation pathways for endocannabinoids but may mimic or modulate the endocannabinoids or even display alternative pharmacology. Similarly, A-EA and 2-AG may be oxidized by P450 enzymes. Again a very diverse number of metabolites are formed, with either cannabinoid-like biological properties or an introduction of disparate pharmacology. The biological activity of epoxy and hydroxyl derivatives of the endocannabinoids remains to be fully elucidated. This review attempts to consolidate and compare the findings obtained to date in an increasingly important research area. This article is part of a Special Issue entitled "Oxygenated metabolism of PUFA: analysis and biological relevance".

The goal of the study was to examine secreted protein response and withdrawal profiles from cultured human trabecular meshwork (HTM) cells following short- and long-term glucocorticoid treatment. Primary cultures of five human HTM cell strains isolated from 5 different individual donor eyes were tested. Confluent HTM cells were differentiated in culture media containing 1% FBS for at least one week, and then treated with Dexamethasone (Dex, 100 nM) 3 times/week for 1 or 4 weeks. Cell culture supernatants were collected 3 times per week for 8 weeks. Secretion profiles of myocilin (MYOC), matrix metalloproteinase-2 (MMP2) and fibronectin (FN) were determined by Western blot analysis and MMP2 activity by zymography. Dex treatment reduced MMP2 expression and activity, returning to normal levels shortly after Dex withdrawal in 5 HTM cell strains. All five cell strains significantly upregulated MYOC in response to Dex treatment by an average of 17-fold, but recovery to basal levels after Dex withdrawal took vastly different periods of time depending on cell strain and treatment duration. Dex treatment significantly increased FN secretion in all strains but one, which decreased FN secretion in the presence of Dex. Interestingly, secretion of FN and MYOC negatively correlated during a 4 week recovery period following 4 weeks of Dex treatment. Taken together, the time course and magnitude of response and recovery for three different secreted, extracellular matrix-associated proteins varied greatly between HTM cell strains, which may underlie susceptibility to glucocorticoid-induced ocular hypertension.

Balding causes widespread psychological distress but is poorly controlled. The commonest treatment, minoxidil, was originally an antihypertensive drug that promoted unwanted hair. We hypothesized that another serendipitous discovery, increased eyelash growth side-effects of prostamide F2α-related eyedrops for glaucoma, may be relevant for scalp alopecias. Eyelash hairs and follicles are highly specialized and remain unaffected by androgens that inhibit scalp follicles and stimulate many others. Therefore, we investigated whether non-eyelash follicles could respond to bimatoprost, a prostamide F2α analog recently licensed for eyelash hypotrichosis. Bimatoprost, at pharmacologically selective concentrations, increased hair synthesis in scalp follicle organ culture and advanced mouse pelage hair regrowth in vivo compared to vehicle alone. A prostamide receptor antagonist blocked isolated follicle growth, confirming a direct, receptor-mediated mechanism within follicles; RT-PCR analysis identified 3 relevant receptor genes in scalp follicles in vivo. Receptors were located in the key follicle regulator, the dermal papilla, by analyzing individual follicular structures and immunohistochemistry. Thus, bimatoprost stimulates human scalp follicles in culture and rodent pelage follicles in vivo, mirroring eyelash behavior, and scalp follicles contain bimatoprost-sensitive prostamide receptors in vivo. This highlights a new follicular signaling system and confirms that bimatoprost offers a novel, low-risk therapeutic approach for scalp alopecias.—Khidhir, K. G., Woodward, D. F., Farjo, N. P., Farjo, B. K., Tang, E. S., Wang, J. W., Picksley, S. M., and Randall, V. A. The prostamide-related glaucoma therapy, bimatoprost, offers a novel approach for treating scalp alopecias.

Purpose To assess the health, functional characteristics, and health care service needs of youth and young adults with special health care needs attending a comprehensive, noncategorical transition program. Methods A self-administered survey was developed from national health surveys and clinical experience to assess concepts identified as important for successful transition to adulthood. Surveys were mailed to 198 parents of youth and young adults with special health care needs attending the transition clinic. Parents were asked about the youth's health, functional status, and health care services needed. The clinical database provided demographic and patient health characteristics. Results were compared against the 2005–2006 National Survey of Children with Special Health Care Needs. Results Forty-four percent of surveys were returned. Average age of youth was 17.5 (11–22) years old and diagnoses included cerebral palsy (36%), spina bifida (10%), developmental delay or Down syndrome (17%), and autism (6%). Most youth needed assistance with personal care (69%) and routine needs (91%) and used assistive devices (59%). Compared with the 2005–2006 National Survey of Children with Special Health Care Needs, parents reported higher needs for all services except mental health care and tobacco or substance use counseling. Forty three percent reported at least one unmet health need. Few parents reported the need for counseling on substance use (1%), sexual health screening (16%), nutrition (34%), and exercise (41%). Conclusions Youth attending our transition program had more functional limitations, poorer reported health status, different diagnosis distribution, and higher levels of needed health services. Few parents identified needs for other recommended adolescent preventive services. Transition programs should assess patient health characteristics and service needs to design effective patient-centered services.

D(1) dopamine receptors are primary mediators of dopaminergic signaling in the CNS. These receptors internalize rapidly following agonist-induced activation, but the functional significance of this process is unknown. We investigated D(1) receptor endocytosis and signaling in HEK293 cells and cultured striatal neurons using real-time fluorescence imaging and cAMP biosensor technology. Agonist-induced activation of D(1) receptors promoted endocytosis of receptors with a time course overlapping that of acute cAMP accumulation. Inhibiting receptor endocytosis blunted acute D(1) receptor-mediated signaling in both dissociated cells and striatal slice preparations. Although endocytic inhibition markedly attenuated acute cAMP accumulation, inhibiting the subsequent recycling of receptors had no effect. Further, D(1) receptors localized in close proximity to endomembrane-associated trimeric G protein and adenylyl cyclase immediately after endocytosis. Together, these results suggest a previously unanticipated role of endocytosis, and the early endocytic pathway, in supporting rapid dopaminergic neurotransmission.

Much has been written about the interaction of stressors (physical, social, and psychological) and alcohol addiction based on studies in humans and preclinical models. We begin by considering the signifi cance and complexity of alcoholism and the options for effectively modeling it in animals, particularly rodents. We then focus on the following aspects of stress-alcohol interactions: (1) compulsive alcohol consumption, characterized by continued intake despite the presence of stressful or aversive consequences; (2) the possible relationship between acute stress and increased alcohol intake; (3) an apparent cross sensitization of stress and alcohol exposure, which increases both future reactivity to stress and the risk of developing alcohol addiction; and (4) efforts to target stress in therapeutic interventions for alcoholism. We also describe possible neuroadaptations and genetic factors that may interact with stress to increase susceptibility to alcoholism. Throughout, we describe the challenges and inconsistencies inherent in both human and animal studies of alcoholism, its etiology, and its impacts. We believe the relationship between preclinical and human studies is of paramount importance to understand addiction-related behavior in humans and to direct, improve, and expand animal models. It is our hope that a full understanding of the mechanistic bases of pathological alcohol intake will have translational benefi ts for the development of behavioral and pharmacological therapies.

Prostanoids modulate the activity of human pregnant myometrium and their functional role can be appreciated through characterisation of prostanoid receptors and tissue concentration of prostanoids. We have applied a lipidomic approach to elucidate the profile of prostanoids in human non-labouring and labouring myometrium. We have identified a total of nineteen prostanoids including prostacyclin, thromboxanes, prostaglandins and dihydro-prostaglandins. Prostacyclin was the predominant prostanoid in both non-labouring and labouring myometria, with PGD(2) and PGF(2alpha) being the second most abundant. Although the total amount of prostanoids was increased in the labouring tissue, PGE(2) and 13,14-dihydro-15-keto-PGE(2) were the only prostanoids to increase significantly at early and late labour (p< or =0.001). Our data suggest that PGF(2alpha) plays an important role in parturition, whilst the increase in PGE(2) could occur to facilitate cervical dilation and relaxation of the lower myometrium during labour. Although the elevation in TXA(2) was less marked than expected, in terms of translation to function even a relatively small increase in the level of this potent spasmogen may have significant effects.

Identification of the primary products of cyclo-oxygenase (COX)/prostaglandin synthase(s), which occurred between 1958 and 1976, was followed by a classification system for prostanoid receptors (DP, EP(1), EP(2) ...) based mainly on the pharmacological actions of natural and synthetic agonists and a few antagonists. The design of potent selective antagonists was rapid for certain prostanoid receptors (EP(1), TP), slow for others (FP, IP) and has yet to be achieved in certain cases (EP(2)). While some antagonists are structurally related to the natural agonist, most recent compounds are 'non-prostanoid' (often acyl-sulphonamides) and have emerged from high-throughput screening of compound libraries, made possible by the development of (functional) assays involving single recombinant prostanoid receptors. Selective antagonists have been crucial to defining the roles of PGD(2) (acting on DP(1) and DP(2) receptors) and PGE(2) (on EP(1) and EP(4) receptors) in various inflammatory conditions; there are clear opportunities for therapeutic intervention. The vast endeavour on TP (thromboxane) antagonists is considered in relation to their limited pharmaceutical success in the cardiovascular area. Correspondingly, the clinical utility of IP (prostacyclin) antagonists is assessed in relation to the cloud hanging over the long-term safety of selective COX-2 inhibitors. Aspirin apart, COX inhibitors broadly suppress all prostanoid pathways, while high selectivity has been a major goal in receptor antagonist development; more targeted therapy may require an intermediate position with defined antagonist selectivity profiles. This review is intended to provide overviews of each antagonist class (including prostamide antagonists), covering major development strategies and current and potential clinical usage.

Prostaglandin F (PGF) ethanolamide (prostamide F) synthase, which catalyzed the reduction of prostamide H(2) to prostamide F(2alpha), was found in mouse and swine brain. The enzyme was purified from swine brain, and its amino acid sequence was defined. The mouse enzyme consisted of a 603-bp open reading frame coding for a 201-amino acid polypeptide with a molecular weight of 21,669. The amino acid sequence placed the enzyme in the thioredoxin-like superfamily with Cys(44) being the active site. The enzyme expressed in Escherichia coli as well as the native enzyme catalyzed not only the reduction of prostamide H(2) to prostamide F(2alpha) but also that of PGH(2) to PGF(2alpha). The V(max) and K(m) values for prostamide H(2) were about 0.25 micromol/min.mg of protein and 7.6 microm, respectively, and those for PGH(2) were about 0.69 micromol/min.mg of protein and 6.9 microm, respectively. Neither PGE(2) nor PGD(2) served as a substrate for this synthase. Based on these data, we named the enzyme prostamide/PGF synthase. Although the enzyme showed a broad specificity for reductants, reduced thioredoxin preferentially served as a reducing equivalent donor for this enzyme. Moreover, Northern and Western blot analyses in addition to the prostamide F synthase activity showed that the enzyme was mainly distributed in the brain and spinal cord, and the immunohistochemical study in the spinal cord showed that the enzyme was found mainly in the cytosol. These results suggest that prostamide/PGF synthase may play an important functional role in the central nervous system.

Ocular hypotensive agents are the only approved pharmacotherapy for glaucoma. Despite significant advances during the past two decades, a large proportion of glaucoma patients require more than one drug. The most recent additions to the armamentarium of antiglaucoma drugs are fixed-combination products for the glaucoma patient who is insufficiently responsive to monotherapy. Fixed-combination products have the combined efficacy of two ocular hypotensive drugs, and the convenience of a two-drug treatment regimen in a single container, which may aid patient adherence to treatment. Available fixed-combination products consist of timolol 0.5% as an invariant with brimonidine 0.2%, dorzolamide 2%, travoprost 0.004%, latanoprost 0.005% or bimatoprost 0.03%. Research on more advanced antiglaucoma medications continues. Promising new directions appear to be the Rho-kinase inhibitors, microtubule-disrupting agents, serotonergics and cannabimimetics. Efforts continue to improve existing antiglaucoma drugs in an attempt to design second-generation cholinomimetics, adrenergics, prostaglandins and prostamides.

The aim of glaucoma therapy is to preserve vision by reducing intraocular pressure (IOP). Following recent National Eye Institute sponsored studies, it is becoming increasingly apparent that every mmHg of extra IOP lowering counts. Bimatoprost is the newest and most effective addition to the physician's armamentarium of ocular hypotensive drugs. Direct clinical comparisons have demonstrated that it is more efficacious than the prostaglandin (PG) FP receptor agonist prodrugs, latanoprost and travoprost, as well as a β-adrenoceptor antagonist, timolol, alone or in fixed combination with the carbonic anhydrase inhibitor, dorzolamide. Moreover, patients that are refractory to latanoprost therapy may be successfully treated with bimatoprost. Such evidence provides support, at the clinical level, for the contention that bimatoprost is pharmacologically distinct from PG FP receptor agonist prodrugs. Bimatoprost is a structural analog of PGF2α-ethanolamide (prostamide F2α), which is formed from the endocannabinoid anandamide by a biosynthetic pathway involving cyclooxygenase-2 (COX-2). Their pharmacology is remarkably similar, such that bimatoprost may be regarded as a prostamide mimetic. The target receptor for bimatoprost and the prostamides appears unique and unrelated to PG- and endocannabinoid-sensitive receptors. Extensive ocular distribution/metabolism studies in non-human primates demonstrate that bimatoprost is not a prodrug, it remains essentially intact. Its profound ocular hypotensive effects may, therefore, be attributed to its prostamide-mimetic properties.

Bimatoprost is a safe and well-tolerated intraocular pressure (IOP) lowering drug that was approved in the United States in 2001 for the treatment of glaucoma and ocular hypertension. It is highly efficacious and produces greater mean reductions in IOP than other currently available antiglaucoma drugs. Conjunctival hyperemia is a common side effect of bimatoprost, but the hyperemia is typically mild and transient. No association has been found between signs of inflammation and the presence of hyperemia in bimatoprost-treated patients. Preclinical studies have elucidated the pharmacological mechanism of bimatoprost-related hyperemia and have examined the possible involvement of inflammation. Bimatoprost, as well as the free acid of latanoprost, elicited endothelium-dependent vasorelaxation in the rabbit jugular vein preparation, a quantitative in vitro model for ocular surface hyperemia (OSH). The vasorelaxant responses to either bimatoprost or latanoprost free acid were significantly inhibited by L-NAME, a nitric oxide synthase inhibitor. Similarly, the in vivo OSH responses to topically applied bimatoprost or latanoprost in dog eyes were significantly inhibited by L-NAME. As predicted, prostaglandin E(2) (PGE(2))-induced conjunctival hyperemia was not inhibited by L-NAME, since PGE(2) has a direct relaxant effect on the vascular smooth muscle. In-life observations and histopathological assessment of ocular surface tissues following bimatoprost treatment were performed for multiple-dose one month, 6 month, or 12 month safety studies in rabbits, dogs, and non-human primates. Results of these studies showed no evidence of bimatoprost-related inflammation in the ocular surface tissues. In summary, OSH related to bimatoprost treatment in laboratory animals occurs by endothelial-derived nitric oxide-mediated vasodilatation and is not associated with inflammation. These studies suggest that conjunctival hyperemia, a side effect of bimatoprost treatment, results from non-inflammatory, pharmacologically based vasodilatation.

Prostaglandin H(2) (PGH(2)) formed from arachidonic acid is an unstable intermediate and is efficiently converted into more stable arachidonate metabolites by the action of enzymes. Prostaglandin F synthase (PGFS) has dual catalytic activities: formation of PGF(2)(alpha) from PGH(2) by the PGH(2) 9,11-endoperoxide reductase activity and 9alpha,11beta-PGF(2) (PGF(2)(alphabeta)) from PGD(2) by the PGD(2) 11-ketoreductase activity in the presence of NADPH. Bimatoprost (BMP), which is a highly effective ocular hypotensive agent, is a PGF(2)(alpha) analogue that inhibits both the PGD(2) 11-ketoreductase and PGH(2) 9,11-endoperoxide reductase activities of PGFS. To examine the catalytic mechanism of PGH(2) 9,11-endoperoxide reductase, a crystal structure of PGFS[NADPH + BMP] has been determined at 2.0 A resolution. BMP binds near the PGD(2) binding site, but the alpha- and omega-chains of BMP are locate on the omega- and alpha-chains of PGD(2), respectively. Consequently, the bound BMP and PGD(2) direct their opposite faces of the cyclopentane moieties toward the nicotinamide ring of the bound NADP. The alpha- and omega-chains of BMP are involved in H-bonding with protein residues, while the cyclopentane moiety is surrounded by water molecules and is not directly attached to either the protein or the bound NADPH, indicating that the cyclopentane moiety is movable in the active site. From the complex structure, two model structures of PGFS containing PGF(2)(alpha) and PGH(2) were built. On the basis of the model structures and inhibition data, a putative catalytic mechanism of PGH(2) 9,11-endoperoxide reductase of PGFS is proposed. Formation of PGF(2)(alpha) from PGH(2) most likely involves a direct hydride transfer from the bound NADPH to the endoperoxide of PGH(2) without the participation of specific amino acid residues.

Prostaglandin F2alpha 1-ethanolamide (prostamide F2alpha) is a potent ocular hypotensive agent in animals and represents a new class of fatty acid amide compounds. Accumulated evidence indicated that anandamide, an endogenous bioactive ligand for cannabinoid receptors, may serve as a common substrate to produce all prostamides, including prostamide F2alpha. After incubation of anandamide with cyclooxygenase 2 (COX-2), the reaction mixture was profiled by HPLC and an intermediate metabolite was discovered and characterized as a cyclic endoperoxide ethanolamide using HPLC-tandem mass spectrometry. Formation of prostamide F2alpha was also demonstrated when the intermediate metabolite was isolated and incubated with prostaglandin F synthase (PGF synthase). These results suggest that the biosynthesis of prostamide F2alpha proceeds in two consecutive steps: oxidation of anandamide to form an endoperoxide intermediate by COX-2, and reduction of the endoperoxide intermediate to form prostamide F2alpha by PGF synthase. This endoperoxide ethanolamide intermediate has been proposed as prostamide H2.

A helpless patient was administered 1 GBq of I to ablate thyroid remnants post-thyroidectomy. The patient was quadriplegic, doubly incontinent and unable to swallow. Published data suggest that nursing staff may receive a total effective dose of 3400 microSv when dealing with such a patient for one 8 h shift per day for 7 days post-treatment.To quantify the effective doses received by nursing staff on dealing with a helpless patient undergoing radioiodine ablation therapy.After intravenous administration of 131I, the whole-body doses received by nursing staff were measured using electronic personal dosemeters for 7 days. The nursing staff recorded the times spent in contact with the patient and the activities performed during these times.The total effective dose received by nursing staff over 7 days was 148 microSv. A nurse working alone for one 8 h shift per day for 7 days could receive an effective dose of 91 microSv. The nursing staff spent an average of 23 min (standard deviation, 15 min) per 8 h shift dealing with the patient. Nursing duties were performed at a contact distance of approximately 0.5 m from the patient.The nursing contact times required for the management of a helpless patient post-radioiodine therapy are lower than previously estimated. It is possible to successfully treat such a patient whilst keeping the effective doses to nursing staff within appropriate constraints. The measured nursing contact times provide an up-to-date summary of current nursing practice and will be a useful aid in the planning of future treatments.

Drugs acting at dopamine D2 receptors (D2R) are commonly used to alleviate symptoms produced by diseases such as Parkinson's disease, schizophrenia, and depression. A limitation to the use of these drugs is that they sometimes afflict patients with severe side effects. This review discusses recent evidence for several proteins that represent novel mediators of the downstream consequences of D2R activation, since selective targeting of particular D2R-mediated signaling pathways could lead to the development of improved treatments for these devastating diseases.

1. Using gene chip technology, we first identified that PGF(2alpha) (FP agonist) and Butaprost (EP(2) agonist) induced about a five-fold upregulation of Nur77 mRNA expression in hFP-HEK 293/EBNA and hEP(2)-HEK293/EBNA cells. Northern Blot analysis revealed that PGF(2alpha)- and Butaprost-induced upregulation of Nur77 expression are dose- and time-dependent. 2. Both PGF(2alpha) and Butaprost upregulated Nur77 gene expression through the protein kinase C (PKC) pathway. These data are the first showing a link between EP(2) receptor stimulation and protein kinase C activation. Calcineurin was found to be involved downstream of the PKC pathway in PGF(2alpha)-induced Nur77 expression, but not in Butaprost-induced Nur77 expression. 3. We also used Nur77 as a marker gene to compare the effects of PGF(2alpha), Butaprost, and Bimatoprost (a prostamide) on Nur77 expression in human primary trabecular meshwork and ciliary smooth muscle (SM) cells, which are target cells for antiglaucoma drugs. The results showed that PGF(2alpha) and Butaprost, but not Bimatoprost, induced upregulation of Nur77 expression in human TM cells. PGF(2alpha), but not Bimatoprost, dramatically induced upregulation of Nur77 mRNA expression in human ciliary SM cells, whereas Butaprost slightly upregulated Nur77 mRNA expression in SM cells. 4. Nur77 promoter deletion analysis indicated that PGF(2alpha), but not Bimatoprost, activated Nur77 promoter-luciferase reporter in hFP-HEK 293/EBNA cells. Butaprost was less efficacious in inducing Nur77 promoter-luciferase reporter activity in hEP(2)-HEK293/EBNA cells relative to PGF(2alpha) in the comparable assay. The data for Nur77 promoter functional analysis were matched to the Northern blot analysis. 5. It appears that PGF(2alpha) and Butaprost activate Nur77 transcription mechanisms through the activation of FP and EP(2) receptor-coupled signaling pathways, whereas Bimatoprost stimulates neither FP nor EP(2) receptors.

Prostaglandin (PG) D(2) ethanolamide (prostamide D(2)) was reduced to 9alpha,11beta-PGF(2) ethanolamide (9alpha,11beta-prostamide F(2)) by PGF synthase, which also catalyzes the reduction of PGH(2) and PGD(2) to PGF(2alpha) and 9alpha,11beta-PGF(2), respectively. These enzyme activities were measured by a new method, the liquid chromatographic-electrospray ionization-mass spectrometry (LC/ESI/MS) technique, which could simultaneously detect the substrate and all products. PGF(2alpha), 9alpha,11beta-PGF(2), PGD(2), PGH(2), 9alpha,11beta-prostamide F(2), and prostamide D(2) were separated on a TSKgel ODS 80Ts column, ionized by electrospray, and detected in the negative mode. Selected ion monitoring (SIM) of m/z 353 ([M-H](-)), 353 ([M-H](-)), 351 ([M-H](-)), 333 ([M-H-H(2)O](-)), 456 ([M+59](-)), and m/z 358 ([M-37](-)) was used for quantifying PGF(2alpha), 9alpha,11beta-PGF(2), PGD(2), PGH(2), 9alpha,11beta-prostamide F(2), and prostamide D(2), respectively. The detection limit for PGF(2alpha) and 9alpha,11beta-PGF(2) was 0.01pmol; that for PGH(2) and PGD(2), 0.1pmol; and that for prostamide D(2) and 9alpha,11beta-prostamide F(2), 0.5 and 0.03pmol, respectively. The LC/ESI/MS technique for measuring PGF synthase activity showed higher sensitivity than other methods. Using this method, we found that Bimatoprost, the ethyl amide analog of 17-phenyl-trinor PGF(2alpha) and an anti-glaucoma agent, inhibited all three reductase activities of PGF synthase when used at a low concentration. These results suggest that Bimatoprost also behaves as a potent PGF synthase inhibitor in addition to having prostamide-like activity.

Connective tissue growth factor (CTGF) and Cyr61 (cysteine-rich angiogenic protein 61) are members of the CCN gene family that encode multifunctional, extracellular matrix-associated signaling proteins. Because the mechanism of action of certain anti-glaucoma drugs involves extracellular matrix remodeling of ocular ciliary muscle, with a resultant increase in drainage of aqueous humor from the eye, we compared the effects of three pharmacologically distinct ocular hypotensive agents on Cyr61 and CTGF gene expression. Thus, prostaglandin F2alpha (PGF2alpha) (FP receptor agonist), Butaprost (EP2 receptor agonist), and Bimatoprost (a prostamide) were compared. Using Affymetrix gene chip technology, we first identified that PGF2alpha dramatically up-regulated Cyr61 and CTGF mRNA expression in HEK 293/EBNA cells (hFP-HEK 293/EBNA). Northern blot further confirmed the Cyr61 and CTGF up-regulation is in a dose- and time-dependent manner. PGF2alpha-induced up-regulation of Cyr61 appeared to exclusively involve the Rho pathway, and up-regulation of CTGF was via multiple intracellular pathways. Because prostamide receptors are, to date, defined only at the pharmacological level, Bimatoprost effects on Cyr61 and CTGF were studied in the isolated feline iris sphincter preparation, a tissue highly responsive to prostamides. Both PGF2alpha and Bimatoprost up-regulated Cyr61 mRNA expression in the cat iris tissue. Only PGF2alpha up-regulated CTGF mRNA expression in the cat iris. Therefore, PGF2alpha and Bimatoprost appear to interact with different receptors populations in the cat iris, according to their markedly different effects on CTGF. Activation of prostaglandin EP2 receptors (Gs-coupled) also up-regulated Cyr61 but not CTGF mRNA expression in the isolated cat iris. Similar data were observed in human primary ciliary smooth muscle cells. Thus, despite quite different signal transduction pathways, FP receptor stimulation up-regulates CTGF and Cyr61. The prostamide analog Bimatoprost and an EP2-selective agonist affects only Cyr61.

Replacement of the carboxylic acid group of prostaglandin (PG) F(2alpha) with a nonacidic moiety, such as hydroxyl, methoxy, or amido, results in compounds with unique pharmacology. Bimatoprost (AGN 192024) is also a pharmacologically novel PGF(2alpha) analog, where the carboxylic acid is replaced by a neutral ethylamide substituent. Bimatoprost potently contracted the feline lung parenchymal preparation (EC(50) value of 35-55 nM) but exhibited no meaningful activity in a variety of PG-sensitive tissue and cell preparations. Its activity seemed unrelated to FP receptor stimulation according to the following evidence. 1) Bimatoprost exhibited no meaningful activity in tissues and cells containing functional FP receptors. 2) Bimatoprost activity in the cat lung parenchyma is not species-specific because its potent activity in this preparation could not be reproduced in cells stably expressing the feline FP receptor. 3) Radioligand binding studies using feline and human recombinant FP receptors exhibited minimal competition versus [(3)H]17-phenyl PGF(2a) for Bimatoprost. 4) Bimatoprost pretreatment did not attenuate PGF(2alpha)-induced Ca(2+) signals in Swiss 3T3 cells. 5) Regional differences were apparent for Bimatoprost but not FP agonist effects in the cat lung. Bimatoprost reduced intraocular pressure in ocular normotensive and hypertensive monkeys over a 0.001 to 0.1% dose range. A single-dose and multiple-dose ocular distribution/metabolism studies using [(3)H]Bimatoprost (0.1%) were performed. Within the globe, bimatoprost concentrations were 10- to 100-fold higher in anterior segment tissues compared with the aqueous humor. Bimatoprost was overwhelmingly the predominant molecular species identified at all time points in ocular tissues, indicating that the intact molecule reduces intraocular pressure.

Prostanoid analogs have recently been introduced into clinical use for the management of increased intraocular pressure (IOP). This class of compounds is known to exert effects on vascular components and some endogenous parent prostaglandins have been shown to alter regional ocular blood flow and exhibit significant vasoactive properties in isolated ocular blood vessels, so the possibility exists that prostanoids could affect the ocular microcirculation either by absorption into the systemic circulation or by direct localized activity on the retinal microvasculature. Thus, the aim of this study was to examine systematically the effects of a broad variety of agonists that exhibit preferential activity at EP(1)-, EP(2)-, EP(3)-, FP-, DP-, IP-, and TP-prostanoid receptor sites on microvessel caliber in the microvasculature associated with human retinal tissues grafted into the hamster cheek pouch membrane. The selective DP-receptor agonist, BW245C and the selective TP-receptor agonist, U-46619, were the only compounds tested that exhibited significant vasoactive effects relative to baseline resting diameters in retinal microvessels. A dose-dependent increase in arteriolar caliber was elicited by BW245C over a concentration range of 10(-8)-10(-4)M at the tested 5- and 10-min timepoints. U-46619 evoked a sharp decrease in microvessel diameter within a 10(-7)-10(-4)M gamut, with the dose-response profiles at 5- and 10-min timepoints remaining essentially parallel over the tested range of concentrations. In contrast to the vasoconstriction induced by U-46619, retinal microvessel calibers were not markedly affected by AGN 192093, a thromboxane-like agonist with additional unique properties. No significant changes in human retinal arteriolar diameters relative to baseline were observed in response to a broad panel of parent and derived compounds known to be selective for EP-, FP- and IP-prostanoid receptors.

To determine whether dexamethasone (DEX)-induced ocular hypertension (OHT) in mice mimics the hallmarks of steroid-induced glaucoma (SIG) in humans, including reduced conventional outflow facility (C), increased extracellular matrix (ECM), and myofibroblasts within the outflow pathway.Osmotic mini-pumps were implanted subcutaneously into C57BL/6J mice for systemic delivery of DEX (3-4 mg/kg/d, n = 31 mice) or vehicle (n = 28). IOP was measured weekly by rebound tonometry. After 3 to 4 weeks, mice were euthanized and eyes enucleated for ex vivo perfusion to measure C, for electron microscopy to examine the trabecular meshwork (TM) and Schlemm's canal (SC), or for immunohistochemistry to examine type IV collagen and α-smooth muscle actin. The length of basement membrane material (BMM) was measured along the anterior-posterior extent of SC by electron microscopy. Ultrastructural changes in BMM of DEX-treated mice were compared against archived human SIG specimens.Dexamethasone increased IOP by 2.6 ± 1.6 mm Hg (mean ± SD) over 3 to 4 weeks and decreased C by 52% ± 17% versus controls. Intraocular pressure elevation correlated with decreased C. Dexamethasone treatment led to increased fibrillar material in the TM, plaque-like sheath material surrounding elastic fibers, and myofibroblasts along SC outer wall. The length of BMM underlying SC was significantly increased in mice with DEX and in humans with SIG, and in mice decreased C correlated with increased BMM.Dexamethasone-induced OHT in mice mimics hallmarks of human SIG within 4 weeks of DEX treatment. The correlation between reduced C and newly formed ECM motivates further study using DEX-treated mice to investigate the pathogenesis of conventional outflow obstruction in glaucoma.

The effects of various prostanoids on the growth, melanogenesis and dendrification of cultured iridal melanocytes were studied. Iridal melanocytes were isolated and cultured with medium supplemented with cAMP elevating agents and basic fibroblast growth factor (bFGF) (complete medium). The iridal melanocytes were plated into multiple well plates and cultured with complete medium or various deleted media with or without various prostanoids at different concentrations. After 6 days, the numbers of cells and dendrites were counted and melanin content was measured and compared with controls. Prostaglandin E(2), an EP(2)receptor agonist (AH 13205) and AGN 192093 (thromboxane mimetic) stimulated growth, melanogenesis and dendrification of cultured iridal melanocytes in cAMP-deleted medium. A mixed EP(1)and EP(3)receptor agonist (sulprostone), a EP(4)receptor agonist (ONO-AE1-329), IP receptor agonists (cicaprost or iloprost) and a TP receptor agonist (U-46619) showed no effect. Prostaglandin D(2)showed stimulating effects. However, these stimulating effects could not be blocked by the addition of a DP receptor antagonist (BW A868C). Furthermore, a DP receptor agonist (BW 245C) showed no effects, indicating that the effect of prostaglandin D(2)may involve receptors other than the DP receptor subtype. The present study indicates that: (1) among various EP receptor agonists, only an EP(2)receptor agonist has stimulating effects on iridal melanocytes; (2) DP, IP and TP receptor agonists do not have stimulating effects; and (3) the mechanisms of action of prostaglandin D(2)and AGN 192093 need further study.

The effects of locally administered brimonidine, clonidine, and p-aminoclonidine on microvessel caliber were compared in human retinal tissues grafted into the hamster cheek pouch. Clonidine and p-aminoclonidine, but not brimonidine, potently constricted human retinal microvessels over a broad concentration range. All three agonists elicited significant vasoconstriction in naive hamster cheek pouch microvasculature. The alpha2-adrenoceptor antagonist, rauwolscine, inhibited p-aminoclonidine-induced constriction in naive hamster cheek pouch microvessels, but not p-aminoclonidine-induced effects in retinal grafts. Selective alpha1-adrenoceptor agonists evoked vasoconstriction in retinal grafts only at relatively high concentrations. These differential effects on the retinal microvasculature could not be readily explained solely on the basis of alpha1- or alpha2-adrenoceptor involvement. Clonidine, p-aminoclonidine and brimonidine are also imidazoline derivatives that interact with putative non-adrenergic imidazoline-sensitive binding sites, the so-called I1-imidazoline binding site subtype implicated by some investigators in mediation of peripheral vasoconstriction. As with p-aminoclonidine, the potent vasoconstriction in human retinal microvasculature elicited by moxonidine, an alpha-adrenergic agonist that has also been reported to exhibit selectivity for putative I1-imidazoline binding sites, was not inhibited by the selective alpha-adrenoceptor antagonist, rauwolscine, nor by idazoxan, an antagonist characterized as having substantial activity at putative I2-imidazoline binding sites. These data suggest the possible involvement of an unconventional non-adrenergic imidazoline-sensitive pathway in regulation of microvascular responses in the inner retina, and that drug activity mediated via such an imidazoline-sensitive component could potentially evoke deleterious effects in the retinal microvasculature.

Acoustic cavitation has been implicated as a cause of cell damage by lithotripter shock waves, particularly under in vitro conditions. When red blood cells were exposed to shock waves (from an electrohydraulic lithotripter) while under high hydrostatic pressure (> 80 atm), cell lysis was dramatically reduced over that seen at atmospheric pressure, which is consistent with damage due to acoustic cavitation. However, even at > 120 atm of pressure, lysis was still 97% above that of cells not exposed to shock waves, revealing significant damage that apparently was due to mechanisms other than cavitation. Hydrostatic pressure alone did not cause cell lysis, and shock-wave-dependent damage occurred when the cells were in fluid suspension, or when they were centrifuged to the end of the vial. Shock-wave damage at high pressure increased with increasing shock-wave number, and was seen at 24 and 20 kV, but not at 16 kV. This shock-wave damage at high pressure makes up a noteworthy portion of the total cell injury seen at atmospheric pressure (about 10% at 24 kV), suggesting significant noncavitational injury to cells in vitro. Because cavitation occurs far more readily in vitro than in vivo, the noncavitational damage seen in the present study could represent a substantial portion of cell injury seen in vivo with shock-wave lithotripsy.

The objective of this study was to assess the corneal and scleral permeabilities of natural prostaglandins as well as their prodrugs and analogs through human cornea and sclera in vitro. The "apparent permeability coefficients" (Papp) of natural prostaglandins (PGF2alpha, PGD2 and PGE2), ester prodrugs of PGF2alpha (1-isopropyl PGF2alpha, 11-pivaloyl PGF2alpha and 11,15-dipivaloyl PGF2alpha) and four analogs (16-m-chlorophenoxy tetranor PGF2alpha, 17-phenyl trinor PGF2alpha, 17-phenyl trinor PGE2 and AH 13205) were measured using modified Ussing perfusion chambers and quantitative high performance liquid chromatography. Our results indicate that the corneal penetration of natural prostaglandins (PGs) is poor (the Papp values ranged from 1.65 x 10(-6) to 2.38 x 10(-6) cm/sec), while the PGF2alpha prodrugs showed higher corneal penetration than PGF2alpha. The 11-pivaloyl ester of PGF2alpha penetrated the cornea faster than both 1-isopropyl ester and the lipophilic 11,15-dipivaloyl ester. The PG analogs also showed poor corneal penetration (Papp values ranged from 0.696 x 10(-6) to 1.49 x 10(-6) cm/sec) except for AH 13205. All compounds tested showed good scleral penetration (Papp values ranged from 6.90 x 10(-6) to 17.1 x 10(-6) cm/sec) except PGF2alpha 11,15-dipivaloyl (Papp = 1.22 x 10(-6) cm/sec). The penetration profiles correlated well with tissue uptake ratios (ratio of final tissue concentration to initial dose) for all compounds except 11,15-dipivalate PGF2alpha. All ester prodrugs (but not the PGs and analogs) underwent corneal first-pass metabolism. The study results demonstrate that transcleral absorption may play a significant role in the ocular absorption of these compounds.

Prostamide (prostaglandin ethanolamide) research emerged from two distinct lines of research: 1) the unique pharmacology of the antiglaucoma drug bimatoprost and 2) the discovery that endocannabinoid anandamide was converted by COX-2 to a series of electrochemically neutral prostaglandin (PG) ethanolamides. Bimatoprost pharmacology was found to be virtually identical to that of prostamide F2α. The earliest studies relied on comparison of agonist potencies compared with PGF2α and synthetic prostaglandin F2α (FP) receptor agonists. The subsequent discovery of selective and potent prostamide receptor antagonists (AGN 211334-6, as shown in Fig. 3) was critical for distinguishing between prostamide and FP receptor-mediated effects. The prostamide F2α receptor was then modeled by cotransfecting the wild-type FP receptor with an mRNA splicing variant (altFP4).Bimatoprost is now used therapeutically for treating both glaucoma and eyelash hypotrichosis. Bimatoprost also stimulates hair growth in isolated human scalp hair follicles. A strong effect is also seen in mouse pelage hair, where bimatoprost essentially halves the onset of hair regrowth and the time to achieve full hair regrowth in shaved mice. Beyond glaucoma and hair growth, bimatoprost has potential for reducing fat deposition. Studies to date suggest that preadipocytes are the cellular target for bimatoprost. The discovery of the enzyme prostamide/PGF synthase was invaluable in elucidating the anatomic distribution of prostamide F2α. High expression in the central nervous system provided the impetus for later studies that described prostamide F2α as a nociceptive mediator in the spinal cord. At the translational level, bimatoprost has already provided therapeutics in two distinct areas and the use of both prostamide agonists and antagonists may provide other useful medicaments.

The trapeziometacarpal joint is commonly affected by degenerative arthritis, presenting with pain, stiffness, and swelling at the base of the thumb. When conservative treatment fails, surgical intervention may be warranted based on clinical and radiologic staging as well as patient demand. The concept of replacing the trapeziometacarpal joint remains attractive because of the decreased pain and stiffness, prevention of thumb shortening, and earlier recovery of strength seen with implant arthroplasty. A technique of using a cementless PyroCarbon hemiarthroplasty implant that allows excellent range of motion and decreased postoperative stiffness and pain is presented, with a focus on dorsal capsular reconstruction to prevent subluxation of the implant.

Lipid mediators variedly affect adipocyte differentiation. Anandamide stimulates adipogenesis via CB1 receptors and peroxisome proliferator-activated receptor γ. Anandamide may be converted by PTGS2 (COX2) and prostaglandin F synthases, such as prostamide/prostaglandin F synthase, to prostaglandin F2α ethanolamide (PGF2αEA), of which bimatoprost is a potent synthetic analog. PGF2αEA/bimatoprost act via prostaglandin F2αFP receptor/FP alt4 splicing variant heterodimers. We investigated whether prostamide signaling occurs in preadipocytes and controls adipogenesis. Exposure of mouse 3T3-L1 or human preadipocytes to PGF2αEA/bimatoprost during early differentiation inhibits adipogenesis. PGF2αEA is produced from anandamide in preadipocytes and much less so in differentiating adipocytes, which express much less PTGS2, FP, and its alt4 splicing variant. Selective antagonism of PGF2αEA receptors counteracts prostamide effects on adipogenesis, as does inhibition of ERK1/2 phosphorylation. Selective inhibition of PGF2αEA versus prostaglandin F2α biosynthesis accelerates adipogenesis. PGF2αEA levels are reduced in the white adipose tissue of high fat diet-fed mice where there is a high requirement for new adipocytes. Prostamides also inhibit zebrafish larval adipogenesis in vivo. We propose that prostamide signaling in preadipocytes is a novel anandamide-derived antiadipogenic mechanism.

During simulated manipulation of children's forearm fractures, levels of scattered radiation from both plain radiographs and an image intensifier in different modes were measured at various sites on the surgeon, anaesthetist, radiographer, and patient both with and without recommended shielding. By using fluoroscopy in the pulsed screening mode but allowing only single pulses to occur, radiation levels could be substantially reduced to the eye, thyroid, and gonads of all those exposed. The radiographer and the anaesthetist were so far from the source and guarded by various pieces of equipment that levels were almost unrecordable. Effective dose equivalent for the surgeon using pulsed mode, based on circa six pulses per manipulation, during 100 manipulations per year, would equate to 1 microSv even in the unshielded state (< 0.1 microSv shielded), which is approximately 1/1,000 of background radiation at sea level. Because the current dose limit is 50 mSv (50,000 microSv) per year for employees, we are many orders of magnitude in the safety zone.

Dendritic cells (DCs) are central players in coordinating immune responses, both innate and adaptive. While the role of lipid mediators in the immune response has been the subject of many investigations, the precise role of prostaglandins has often been plagued by contradictory studies. In this study, we examined the role of PGE(2) on human DC function. Although studies have suggested that PGE(2) specifically plays a role in DC motility and cytokine release profile, the precise receptor usage and signaling pathways involved remain unclear. In this report we found that irrespective of the human donor, monocyte-derived dendritic cells (MoDCs) express three of the four PGE(2) receptor subtypes (EP(2-4)), although only EP(2) and EP(4) were active with respect to cytokine production. Using selective EP receptor antagonists and agonists, we demonstrate that PGE(2) coordinates control of IL-23 release (a promoter of Th17, an autoimmune associated T cell subset) in a dose-dependent manner by differential use of EP(2) and EP(4) receptors in LPS-activated MoDCs. This is in contrast to IL-12, which is dose dependently inhibited by PGE(2) through both receptor subtypes. Low concentrations (∼1-10nM) of PGE(2) promoted IL-23 production via EP(4) receptors, while at higher (>50 nM), but still physiologically relevant concentrations, IL-23 is suppressed by an EP(2) dependent mechanism. These results can be explained by differential regulation of the common subunit, IL-12p40, and IL-23p19, by EP(2) and EP(4). By these means, PGE(2) can act as a regulatory switch of immune responses depending on its concentration in the microenvironment. In addition, we believe these results may also explain why seemingly conflicting biological functions assigned to PGE(2) have been reported in the literature, as the concentration of ligand (PGE(2)) fundamentally alters the nature of the response. This finding also highlights the potential of designing therapeutics which differentially target these receptors.

The effects of leukotriene (LT) B4 and D4 on the motility of human peripheral blood neutrophils were investigated employing a novel analytical method. Using the under-agarose technique, migration distance and vectorial orientation of neutrophils in response to selected LT concentrations were determined with the aid of digital image processing. Neutrophil polarization induced by a chemotactic gradient was very apparent even at fields taken adjacent to the cell seeding well where little directional cell motility had occurred. Thus, cell polarization appeared to be the earliest response to chemoattractive LTs. Cell motility occurred in a dose-dependent manner to LTB4 according to determination of the leading edge. LTD4 produced similar effects on neutrophil polarization and motility, but these occurred only at very high concentrations. These data support the view that vectorial orientation is a prerequisite for directional migration of cells and it is also feasible that these are separately regulated events. Furthermore, our studies confirm that LTB4 and, to a much lesser extent, LTD4 are chemotactic for human peripheral blood neutrophils. J. Leukoc. Biol. 55: 201–208; 1994.

It is now more than 15 years since the molecular structures of the major prostanoid receptors were elucidated. Since then, substantial progress has been achieved with respect to distribution and function, signal transduction mechanisms, and the design of agonists and antagonists (http://www.iuphar-db.org/DATABASE/FamilyIntroductionForward?familyId=58). This review systematically details these advances. More recent developments in prostanoid receptor research are included. The DP(2) receptor, also termed CRTH2, has little structural resemblance to DP(1) and other receptors described in the original prostanoid receptor classification. DP(2) receptors are more closely related to chemoattractant receptors. Prostanoid receptors have also been found to heterodimerize with other prostanoid receptor subtypes and nonprostanoids. This may extend signal transduction pathways and create new ligand recognition sites: prostacyclin/thromboxane A(2) heterodimeric receptors for 8-epi-prostaglandin E(2), wild-type/alternative (alt4) heterodimers for the prostaglandin FP receptor for bimatoprost and the prostamides. It is anticipated that the 15 years of research progress described herein will lead to novel therapeutic entities.

Dorsal reduction (humpectomy) is a simple maneuver in principle, yet it commonly results in irregularities and general inaccuracies, along with occasional internal valve compromise. Traditionally, spreader grafts have been applied to reconstruct an internal valve disrupted during dorsal reduction. Imbricating the dissected ends of the upper lateral cartilages at their interface with the septum (spreader flaps) allows the surgeon to use this tissue, which would otherwise be discarded, to reconstruct the internal valve and design an aesthetically pleasing nasal line. The application of a spreader flap is not only an easily reproducible technique to restore middle vault structure but allows for precise incremental control when performed at the time of humpectomy. To that end, the authors provide a detailed description of their internal valve reconstruction technique, which has been honed over the past 15 years.

PURPOSE Activation of prostaglandin (PG)-EP(4) receptors by 3,7-dithiaPGE(1) robustly lowers intraocular pressure in nonhuman primate eyes, which increases outflow facility but has no effect on aqueous secretion or uveoscleral outflow. Because of differences in PG efficacy in outflow function between nonhuman primates and humans, we tested the impact of 3,7-dithiaPGE(1) on conventional outflow function in human donor eyes. METHODS The expression pattern of PG-EP(4) receptors was determined in corneoscleral tissues of human donor eyes and in cultures of human outflow cells by immunofluorescence microscopy and Western blot, respectively. The efficacy of 3,7-dithiaPGE(1) was determined by assaying agonist-stimulated cAMP accumulation and β-arrestin mobilization in cultured human cells. Agonist effects on outflow facility were examined in paired human donor eyes that were perfused at 8 mm Hg of constant pressure, equivalent to 15 mm Hg in vivo. RESULTS The trabecular meshwork (TM) and Schlemm's canal (SC) cells expressed PG-EP(4) receptors. Agonist-mediated effects on the PG-EP(4) receptors were detected in SC (EC(50) = 6.3 × 10(-9) M, n = 4), but not TM (EC(50) = 1.7 × 10(-7) M, n = 5) cells. Effects in SC cells were blocked by the PG-EP(4) receptor-selective antagonist GW627368 (EC(50) = 1.09 × 10(-2) M, n = 4), but not the PG-EP(2) receptor-selective antagonist AH6809 (EC(50) = 4.10 × 10(-9) M, n = 5). Perfused into human eyes at a concentration that selectively activates PG-EP(4) receptors, 3,7-dithiaPGE(1) (10 nM) increased outflow facility by 51% ± 18% over baseline levels in individual drug-treated eyes after drug exchange (n = 6 eyes; P = 0.05) and by 69% ± 23% (P < 0.01) compared with that in contralateral eyes. CONCLUSIONS Activation of PG-EP(4) receptors expressed by SC cells of the human conventional outflow pathway appears to contribute to PG regulation of outflow facility.

Neuroplastic changes in the CNS are thought to be a fundamental component of learning and memory. While pioneering studies in the hippocampus and cerebellum have detailed many of the basic mechanisms that can lead to alterations in synaptic transmission based on previous activity, only more recently has synaptic plasticity been monitored after behavioral manipulation or drug exposure. In this chapter, we review evidence that drugs of abuse are powerful modulators of synaptic plasticity. Both the dopaminergic neurons of the ventral tegmental area as well medium spiny neurons in nucleus accumbens show enhanced excitatory synaptic strength following passive or active exposure to drugs such as cocaine and alcohol. In the VTA, both the enhancement of excitatory synaptic strength and the acquisition of drug-related behaviors depend on signaling through the N-methyl-D: -aspartate receptors (NMDARs) which are mechanistically thought to lead to increased synaptic insertion of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs). Synaptic insertion of AMPARs by drugs of abuse can be long lasting, depending on the route of administration, number of drug exposures, or whether the drugs are received passively or self-administered.

Surprisingly high contractile activity was reported for 11-deoxy-16,16-dimethyl prostaglandin E₂ (DX-DM PGE₂) on pig cerebral artery when used as a selective EP₃ receptor agonist. This study investigated the selectivity profile of DX-DM PGE₂, focusing on the interaction between its EP₃ and TP (thromboxane A₂-like) agonist activities.Contraction of guinea-pig trachea (EP₁ system) and aorta (EP₃ and TP systems) was measured in conventional organ baths.Strong contraction of guinea-pig aorta to sulprostone and 17-phenyl PGE₂ (EP₃ agonists) was only seen under priming with a second contractile agent such as phenylephrine, histamine or U-46619 (TP agonist). In contrast, DX-DM PGE₂ induced strong contraction, which on the basis of treatment with (DG)-3ap (EP₃ antagonist) and/or BMS-180291 (TP antagonist) was attributed to self-synergism arising from co-activation of EP₃ and TP receptors. EP₃/TP self-synergism also accounted for contraction induced by PGF(2α) and its analogues (+)-cloprostenol and latanoprost-FA. DX-DM PGE₂ also showed significant EP₁ agonism on guinea-pig trachea as defined by the EP₁ antagonists SC-51322, (ONO)-5-methyl-1 and AH-6809, although AH-6809 exhibited poor specificity at concentrations ≥3 µM.EP₃/TP self-synergism, as seen with PGE/PGF analogues in this study, may confound EP₃ agonist potency comparisons and the characterization of prostanoid receptor systems. The competitive profile of a TP antagonist may be distorted by variation in the silent/overt contraction profile of the EP₃ system in different studies. The relevance of self-synergism to in vivo actions of natural prostanoid receptor agonists is discussed.

Vision loss associated with glaucoma is treatable if intraocular pressure (IOP) is lowered sufficiently and maintained over time.1 Because of safety issues, frequency of the dosing regimen, and their efficacy as ocular antihypertensive agents, prostaglandin (PG)-F2α mimetics have quickly become the medical treatment of choice for managing IOP in glaucoma patients.2 PG-F2α drugs lower intraocular pressure by 25% to 30% after 1 week of once-a-day administration without the significant ocular and systemic side effects experienced more frequently with other topical medications.3 Moreover, PGs as a class are much better than other topical glaucoma drugs at controlling diurnal IOP fluctuations, which appear to increase the progression of visual field defects.4,5 Early studies on aqueous humor dynamics in monkeys demonstrated that latanoprost, the prototypical FP receptor agonist, lowered IOP exclusively by increasing uveoscleral outflow.6–8 Since these initial reports, recent studies indicate that PGs exert a pronounced effect on pressure-dependent (trabecular/conventional) outflow in human volunteers9,10 and in perfused human anterior segments.11,12 Although the four PGs currently approved as ocular antihypertensive agents (unoprostone, latanoprost, travoprost, and bimatoprost) do not appear to increase conventional outflow in monkeys, a newer, more potent analog (tafluprost) does, increasing conventional outflow by 33%.13 Thus, a class of drugs originally thought to lower IOP solely by effects on uveoscleral outflow clearly impacts conventional outflow. The chief cellular mechanisms by which PGs exert their effects on uveoscleral outflow appear to be a result of extracellular matrix remodeling between longitudinal ciliary muscle fiber bundles. Alteration in matrix metalloproteinase secretion and opening of flow pathways increase uveoscleral outflow over time.14–19 Interestingly, modified flow pathways in chronically treated monkey eyes are lined by endothelial cells, apparently a result of new, organized outflow channel formation between muscle bundles.20 In contrast, the mechanism by which PGs increase conventional outflow in humans is not well understood. Human trabecular meshwork cells express PG-FP receptors,21 and activation of FP receptors in perfused human anterior segments results in both acute (hours) and chronic (days) modulation of outflow facility.11,12 The chronic change appears to correspond to the extracellular matrix remodeling observed in the trabecular meshwork (TM) of monkeys treated with PGs for 1 year20 and the altered matrix metalloproteinase secretion detected in cultured human TM cells.17 The acute increase in outflow facility is consistent with decreased contractility of cultured bovine TM cells.22 Given that previous studies of PG effects on contractility were performed using bovine TM cells and given that Schlemm's canal (SC) cells were not examined, the purpose of the present study was to test the response of PGs on both cell types that populate the human conventional outflow pathway. Using cellular dielectric spectroscopy, we found that bimatoprost significantly increased impedance (an indicator of cell relaxation) of primary cultures of human TM and SC cell monolayers in a receptor-specific manner, suggesting that both cell types mediate effects of PGs on conventional outflow facility.