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BACKGROUND Port-wine stain (PWS) is a congenital capillary malformation that often occurs on the face. Feasible and quantitative evaluation of facial port-wine stain (FPWS) can significantly impact its clinical management and aid in future research. AIM To develop and validate an easy-to-use scoring system for FPWS evaluation. METHODS A facial port-wine stain area and severity index (FSASI) scoring system was proposed. To determine the FSASI score, the face was divided into four regions: forehead, right malar, left malar, and perioral. The severity of FPWS in each region was evaluated by three factors: percentage of the area affected, lesion color, and thickness. To evaluate the intra- and inter-rater reliability of FSASI, two separate FSASI assessments on 111 clinical pictures were conducted by each rater in a one-week interval, and the results from 6 independent raters at different time points were compared. Validity of the FSASI scores was assessed by comparing it with physician global assessment (PGA) and traditional classification data. Validity of the area and color elements of FSASI was also determined. The changes in FSASI scores after vascular-targeted photodynamic therapy (V-PDT) were analyzed to evaluate the treatment effect. RESULTS The FSASI scoring system showed good intra- and inter-rater reliability (ICC >0.75, p

To evaluate the imaging findings and transitional changes in spacer materials used in carbon-ion radiation therapy MATERIALS: Medical records were retrospectively reviewed, and the maximum thickness, volume, and CT value of spacers were calculated from CT scans. Procedure-related complications were recorded.A spacer was surgically placed in six patients in retroperitoneal, presacral, or peritoneal sites. The spacer material was polyglycolic acid (PGA) in four patients and expanded polytetrafluoroethylene (ePTFE) in two patients. The thickness of PGA spacers showed no changes in any patients within 4 weeks, but increased within 6 weeks in one patient and was unchanged or decreased in the remaining patients. PGA spacer volume decreased gradually after placement in three of four patients; this was observed at 4 months in two patients and at 6 months in one patient. The mean CT value of PGA spacers was 83 HU just after placement, and decreased gradually thereafter. Air was seen in the PGA spacers of two patients. Neither ePTFE spacer showed volume changes over time, and the mean CT value was low (mean, -53.7 HU) just after placement but increased rapidly to 145 HU at 2 months.Spacer imaging findings may vary according to type and may change over time. Familiarity with these features is beneficial for diagnostic radiologists.

Amphiphilic block copolymers with a thermoresponsive poly(N-isopropylacrylamide) block and a glycopeptide block are synthesized and particle formation as well as interaction of the glyco-corona with lectins is investigated. The synthetic route comprises the preparation of block copolymers by N-carboxyanhydride polymerization and subsequent deprotection to obtain pH- and thermoresponsive poly(l-glutamic acid)-b-poly(N-isopropylacrylamide) (pGA-b-pNIPAM), which is then further modified with different amino sugars by a versatile coupling method with 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholin-4-ium chloride (DMT-MM). The glycosylated pGA-b-pNIPAM block copolymers are investigated with regard to cloud point temperatures (T

The signaling lipid molecule 15-deoxy-delta 12,14-prostaglandin J2 (15d-PGJ2) has multiple cellular functions, including anti-inflammatory and antineoplastic activities. Here, we report that 15d-PGJ2 blocks translation through inactivation of translational initiation factor eIF4A. Binding of 15d-PGJ2 to eIF4A blocks the interaction between eIF4A and eIF4G that is essential for translation of many mRNAs. Cysteine 264 in eIF4A is the target site of 15d-PGJ2. The antineoplastic activity of 15d-PGJ2 is likely attributed to inhibition of translation. Moreover, inhibition of translation by 15d-PGJ2 results in stress granule (SG) formation, into which TRAF2 is sequestered. The sequestration of TRAF2 contributes to the anti-inflammatory activity of 15d-PGJ2. These findings reveal a novel cross-talk between translation and inflammatory response, and offer new approaches to develop anticancer and anti-inflammatory drugs that target translation factors including eIF4A.

A peroxisome proliferator-activated receptor gamma (PPARgamma) ligand, 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)), has been reported to possess anti-inflammatory activity in activated monocytes/macrophages. In this study, we investigated the effect of 15d-PGJ(2) on the lipopolysaccharide (LPS)-induced expression of chemokine mRNAs, especially macrophage inhibitory protein (MIP)-2 (CXCL2), in mouse peritoneal macrophages. The inhibitory actions of the natural PPARgamma ligands, 15d-PGJ(2) and prostaglandin A1 (PGA1), on the expression of RANTES (regulated upon activation, normal T expressed and secreted; CCL5), MIP-1beta (CCL4), MIP-1alpha (CCL3), IFN-gamma-inducible protein 10 kilodaltons (IP-10; CXCL10) and monocyte chemoattractant protein-1 (MCP-1; CCL2) mRNA in LPS-treated cells were stronger than those of the synthetic PPARgamma ligands troglitazone and ciglitazone. However, 15d-PGJ(2) enhanced the expression of LPS-induced MIP-2 (CXCL2) mRNA. A specific PPARgamma antagonist (GW9662) had no effect on the inhibitory action of 15d-PGJ(2) and PGA1 in LPS-induced chemokine mRNA expression and on the synergistic action of 15d-PGJ(2) in LPS-induced MIP-2 (CXCL2) expression. Moreover, LPS itself reduced the expression of PPARgamma. Although the synergistic effect of 15d-PGJ(2) on LPS-induced MIP-2 (CXCL2) mRNA expression was remarkable, the production of MIP-2 (CXCL2) in cells treated with 15d-PGJ(2) and LPS did not increase compared to the production in cells treated with LPS alone. The synergistic action of 15d-PGJ(2) on LPS-induced MIP-2 (CXCL2) mRNA expression was dependent on the activation of nuclear factor-kappaB (NF-kappaB), and 15d-PGJ(2) increased the phosphorylation of p38 and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) in cells stimulated with LPS. These results suggest that the synergistic effect of 15d-PGJ(2) on LPS-induced MIP-2 (CXCL2) expression is PPARgamma-independent, and is mediated by the p38 and SAPK/JNK pathway in mitogen-activated protein kinase signaling pathways, which activates NF-kappaB. Our data may give more insights into the different mechanisms contrary to the anti-inflammatory effect of 15d-PGJ(2) on the expression of chemokine genes.

The solid-phase synthesis of a combinatorial cross-conjugated dienone library based on the structure of clavulones and their biological activity are reported. Clavulones are a family of marine prostanoids, and are composed of a cross-conjugated dienone system bearing two alkyl side-chains. The cross-conjugated dienone system irreversibly reacted with two nucleophiles. Our strategy for the solid-phase synthesis of the cross-conjugated dienones involves the Sonogashira-coupling reaction of a solid-supported cyclopentenone 10 bearing an acetylene group, followed by aldol condensation with aldehydes. The diphenyl derivative 7 aA was prepared from the solid-supported cyclopentenone 10 in 56% total yield. Combinatorial synthesis of a small library using twelve halides and eight aldehydes resulted in the production of 74 desired compounds from 98 candidates, and were detected by their mass spectra. Antiproliferative effects of the crude compounds against HeLaS3 cells showed that eleven samples showed strong antitumor activity (IC50

Cyclopentenone prostaglandins (cyPG) with antiinflammatory and antiproliferative properties have been envisaged as leads for the development of therapeutic agents. Because cyPG effects are mediated in part by the formation of covalent adducts with critical signaling proteins, it is important to assess the specificity of this interaction. By using biotinylated derivatives of 15-deoxy-Delta(12,14)-PGJ(2) (15d-PGJ(2)-B) and PGA(1) (PGA(1)-B) we herein provide novel evidence for the differential selectivity of protein modification by distinct cyPG. The marked quantitative and qualitative differences in the binding of 15d-PGJ(2)-B and PGA(1)-B to cellular proteins were related to a differential reactivity in the presence of glutathione (GSH), both in vitro and in intact cells. Therefore GSH levels may influence not only the intensity but also the specificity of cyPG action.

Cyclopentenone prostaglandins are potent inhibitors of a wide variety of RNA and DNA viruses. In this report we describe that prostaglandin A1 (PGA1) potently inhibited the replication of classical swine fever virus in cultures of PK-15 cells. The highest non-toxic dose (5 microg/ml) inhibited virus yield in 99% at the initial phase of infection and in 77% in persistent infected cells. However when PGA1 was removed from persistently infected cells, the inhibition of virus replication was partially reverted.

Cyclopentenone prostaglandins (CyPGs), derivatives of arachidonic acid, have been suggested to exert growth-inhibitory activity through peroxisome proliferator-activated receptor (PPAR)-dependent and -independent mechanisms. Here we examined various eicosanoids for growth inhibition and found that the terminal derivative of prostaglandin (PG) J(2) metabolism, 15-deoxy-Delta(12,14)-PGJ(2) (15d-PGJ(2)), and PGA(1) markedly inhibited the growth and induced apoptosis in AGS gastric carcinoma cells. There were no significant increases in cell death and DNA-fragmentation in the cells with overexpression of PPARalpha or PPARgamma, indicating the possibility that 15d-PGJ(2) and PGA(1) induced apoptosis through PPAR-independent pathway. Moreover, 15d-PGJ(2) and PGA(1) activated the c-jun N-terminal kinase (JNK) and caspase-3 activity in dose- and time-dependent manners. To examine further the role of JNK signaling cascades in apoptosis induced by 15d-PGJ(2) and PGA(1), we transfected dominant-negative (DN) mutants of JNK plasmid into the cells to analyze the apoptotic characteristics of cells overexpressing DN-JNK following exposure to 15d-PGJ(2) and PGA(1). Overexpression of DN-JNK significantly repressed both endogenous JNK and caspase-3 activity, and subsequently decreased apoptosis induced by 15d-PGJ(2) and PGA(1). These results suggested that CyPGs, such as 15d-PGJ(2) and PGA(1), activated JNK signaling pathway, and that JNK activation may be involved in 15d-PGJ(2)- and PGA(1)-induced apoptosis.

This study was designed to investigate the effects of various chemically distinct activators of PPAR-gamma and PPAR-alpha in a rat model of acute myocardial infarction. Using Northern blot analysis and RT-PCR in samples of rat heart, we document the expression of the mRNA for PPAR-gamma (isoform 1 but not isoform 2) as well as PPAR-beta and PPAR-alpha in freshly isolated cardiac myocytes and cardiac fibroblasts and in the left and right ventricles of the heart. Using a rat model of regional myocardial ischemia and reperfusion (in vivo), we have discovered that various chemically distinct ligands of PPAR-gamma (including the TZDs rosiglitazone, ciglitazone, and pioglitazone, as well as the cyclopentanone prostaglandins 15D-PGJ2 and PGA1) cause a substantial reduction of myocardial infarct size in the rat. We demonstrate that two distinct ligands of PPAR-alpha (including clofibrate and WY 14643) also cause a substantial reduction of myocardial infarct size in the rat. The most pronounced reduction in infarct size was observed with the endogenous PPAR-gamma ligand, 15-deoxyDelta12,14-prostagalndin J2 (15D-PGJ2). The mechanisms of the cardioprotective effects of 15D-PGJ2 may include 1) activation of PPAR-alpha, 2) activation of PPAR-gamma, 3) expression of HO-1, and 4) inhibition of the activation of NF-kappaB in the ischemic-reperfused heart. Inhibition by 15D-PGJ2 of the activation of NF-kappaB in turn results in a reduction of the 1) expression of inducible nitric oxide synthase and the nitration of proteins by peroxynitrite, 2) formation of the chemokine MCP-1, and 3) expression of the adhesion molecule ICAM-1. We speculate that ligands of PPAR-gamma and PPAR-alpha may be useful in the therapy of conditions associated with ischemia-reperfusion of the heart and other organs. Our findings also imply that TZDs and fibrates may help protect the heart against ischemia-reperfusion injury. This beneficial effect of 15D-PGJ2 was associated with a reduction in the expression of the 1) adhesion molecules ICAM-1 and P-selectin, 2) chemokine macrophage chemotactic protein 1, and 3) inducible isoform of nitric oxide synthase. 15D-PGJ2 reduced the nitration of proteins (immunohistological analysis of nitrotyrosine formation) caused by ischemia-reperfusion, likely due to the generation of peroxynitrite. Not all of the effects of 15D-PGJ2, however, are due to the activation of PPAR-gamma. For instance, exposure of rat cardiac myocytes to 15D-PGJ2, but not to rosiglitazone, results in an up-regulation of the expression of the mRNA for heme-oxygenase-1 (HO-1). Taken together, these results provide convincing evidence that several, chemically distinct ligands of PPAR-gamma reduce the tissue necrosis associated with acute myocardial infarction.

Cyclopentenone prostaglandins (PGs) are known to arrest the cell cycle at the G1 phase in vitro and to suppress tumor growth in vivo. However, their effects on neurons are unclear. Here, we report that some cyclopentenone PGs function as neurite outgrowth-promoting factors. They promoted neurite outgrowth from PC12 cells and from dorsal root ganglion explants but only in the presence of nerve growth factor (NGF). We refer to these PGs as neurite outgrowth-promoting PGs (NEPPs). Through study of the structure-function relationship of NEPP1-10 and related compounds, we found that the cross-conjugated dienone moiety of NEPPs was essential for promoting neurite outgrowth, and NEPP10 was concluded to be the best candidate for drug development. We also investigated the intracellular mechanism of the promotion by NEPPs and obtained evidence that immunoglobulin heavy chain binding protein/glucose-regulated protein 78 (BiP/GRP78) plays a role in the promotion, based on the following observations: Antisense nucleotides for BiP/GRP78 gene blocked the promotion of neurite outgrowth; BiP/GRP78 protein level increased in response to NEPPs; and overexpression of BiP/GRP78 protein by adenoviral gene transfer promoted the neurite outgrowth by NGF.

Cyclopentenone prostaglandins inhibit the replication of several DNA and RNA viruses, including retroviruses. The antiviral activity has been associated with the induction of a 70-kDa heat-shock protein (HSP70), via activation of the heat-shock transcription factor (HSF) in infected cells. In the present study we investigated the effect of prostaglandin A1 (PGA1) on the regulation of HSP70 gene expression as well as on viral RNA and protein synthesis in CEM-SS cells during acute infection with human immunodeficiency virus type 1 (HIV-1). We report that HIV-1 infection does not alter HSF activation by PGA1, whereas it causes an increase in intracellular HSP70 mRNA levels, as a result of enhanced HSP70 mRNA stability. We also show that, as reported in studies of different virus/host cell models, PGA1 inhibits HIV-1 replication by acting at multiple levels during HIV-1 infection. In addition to the previously reported block of HIV-1 mRNA transcription, PGA1 was also found to inhibit viral protein synthesis. These results, together with the fact that prostaglandins are used clinically in the treatment of several diseases, open new perspectives in the search for novel antiretroviral drugs.

The cyclopentenone prostaglandins (cPG) 15-deoxy-Delta12,14-prostaglandin J2 (dPGJ2) and PGA1 can inhibit multiple steps in nuclear factor (NF)-kappaB signaling and can induce cell death. Here we characterized the effects of dPGJ2 and PGA1 on the inflammatory induction of endothelial cell adhesion molecules (CAM). Pretreatment of endothelial cells with dPGJ2 or PGA1 at low concentrations dose dependently inhibited the up-regulation of CAM expression and monocyte arrest by tumor necrosis factor (TNF)-alpha but not expression of inhibitor of apoptosis proteins. Only at high concentrations, cPG enhanced TNF-alpha-induced cell death and inhibited TNF-alpha-induced IkappaB-alpha kinase (IKK) activation, IkappaB-alpha degradation, and NF-kappaB/p65 translocation, while promoting AP-1/c-jun phosphorylation. Expression of an IKK-beta mutant (C179A) resistant to interaction with cPG impaired cell death induction but not inhibition of CAM up-regulation by cPG. Gel shift and reporter gene analysis revealed that cPG at low concentrations directly impaired DNA binding of NF-kappaB and NF-kappaB-dependent transactivation. The synthetic analogs dPGA1 or dPGA2 were ineffective, indicating structural specificity of cPG. Thus, the suppression of endothelial CAM up-regulation with cPG is dissociated from cell death sensitization and IKK inhibition above threshold concentrations and related to interference with NF-kappaB binding. Our findings define distinct mechanisms for anti-inflammatory and proapoptotic effects of cPG in endothelial cells.

BACKGROUND: With the improvement of ultrasound technology, the likelihood of detection of major fetal structural anomalies in mid‐pregnancy has increased considerably. Upon the detection of serious anomalies, women typically are offered the option of pregnancy termination. Additionally, there are still many reasons other than fetal anomalies why women seek abortion in the mid‐trimester. OBJECTIVES: To compare different methods of second trimester medical termination of pregnancy for their efficacy and side‐effects. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, Popline and reference lists of retrieved papers and other sources. SELECTION CRITERIA: All randomised controlled trials (RCTs) examining medical regimens for termination of pregnancy of a singleton living fetus between 12‐28 weeks' gestation were analysed. The outcome measures were the induction to abortion interval, abortion rate within 24 hours, need for surgical evacuation, blood loss, uterine rupture, pain, and side‐effects.Trials including >20% fetal death, multiple pregnancies, previous uterine scars and regimens which involved cervical preparation were excluded. DATA COLLECTION AND ANALYSIS: Two authors selected the trials and three authors extracted data. MAIN RESULTS: Fourty RCTs were included, addressing various agents for pregnancy termination and methods of administration. When used alone, misoprostol was an effective inductive agent, though it appeared to be more effective in combination with mifepristone. However, the evidence from RCTs is limited. Misoprostol was preferably administered vaginally, although among multiparous women sublingual administration appeared equally effective. A range of doses of vaginally administered misoprostol has been used. No randomised trials comparing doses of misoprostol were identified; however low doses of misoprostol appear to be associated with fewer side‐effects while moderate doses appear to be more efficient in completing abortion. Four RCTs showed that the induction to abortion interval with 3‐hourly vaginal administration of prostaglandins is shorter than 6‐hourly administration without an increase in side‐effects. Many studies reported the need for surgical evacuation. Indications for surgical evacuation include retained products of the placenta and heavy vaginal bleeding. Fewer women required surgical evacuation when misoprostol was administrated vaginally compared with women receiving intra‐amniotical PGF(2a). Mild, self‐limiting diarrhoea was more common among women who received misoprostol compared to other agents. AUTHORS' CONCLUSIONS: Medical abortion in the second trimester using the combination of mifepristone and misoprostol appeared to have the highest efficacy and shortest abortion time interval. Where mifepristone is not available, misoprostol alone is a reasonable alternative. The optimal route for administering misoprostol is vaginally, preferably using tablets at 3‐hourly intervals. Apart from pain, the side‐effects of vaginal misoprostol are usually mild and self limiting. Conclusions from this review are limited by the gestational age ranges and variable medical regimens, including dosing, administrative routes and intervals of medication, of the included trials.

Prostaglandin (PG) A and J exert anti-viral and anti-proliferative effects in a number of experimental models. In particular, multiple treatments with PGAs prevent in vitro the clonal selection of HTLV-l-infected and potentially transformed cord-blood-derived mononuclear cells. Proliferation of HTLV-I-infected leukemic T cells is refractory in most cases to conventional anti-blastic therapy. We examined whether these cyclo-pentenone PGs might control cell proliferation and/or alter virus replication also in HTLV-l-transformed cells. We show that PGA1 and PGJ2 can exert powerful control of proliferation of the HTLV-l-immortalized, virus-producing MT-2 cell line, in a concentration-dependent fashion. Cells were preferentially arrested at the G1/S interface by treatment with PGA1 or PGJ2 without any detectable cellular toxicity. The anti-proliferative effect of PG treatment was independent of the growth phase of MT-2 cells, since both asynchronous and synchronous cells were sensitive to treatment. This effect was accompanied by an increase in the synthesis of a 70 kDa heat-shock protein (HSP70). However, synthesis of HSP70 was induced to a much greater extent by PGJ2 than by PGA1 at the same concentration. Neither PGA1 or PGJ2 inhibited the transcription of HTLV-I in MT-2 cells, but treatment with PGJ2, and not with PGA1, moderately inhibited the synthesis of viral proteins, i.e., p40 Tax and p19 core proteins. Moreover, infection of recipient K562 cells was significantly inhibited after pre-treatment of MT-2 cells with PGJ2 14 hr before or co-treatment at the onset of the co-culture with K562 cells. This effect was not obtained when MT-2 cells were repeatedly pre-treated with PGJ2 for I week before co-culturing. This suggests that reduced infection could be related to impairment of some step in virus-transmission phase.

We describe the design and synthesis of alkylating reagents based on the structure of clavulones. They are composed of cross-conjugated dienone system and irreversibly reacted with two nucleophiles under mildly basic conditions via beta-elimination. Hydroxyl derivative 7b showed the highest reactivity toward thiols and showed the strongest cytotoxicity in Hela S3 cells among the three derivatives having a different protecting group at the tert-hydroxyl group.

Three marine prostanoids, 1, 2, and 3, were isolated from the extract of the Okinawan soft coral Clavularia viridis. The structures of these compounds were assigned based on the results of spectroscopic analysis. Compound 1 was shown to be preclavulone-A methyl ester, and this is the first isolation of the ester of preclavulone-A as a natural product. Preclavulone-A is proposed to be the key intermediate in the biosynthesis of marine prostanoids exemplified by clavulones in C. viridis. The new prostanoid 3 was suggested to be a biosynthetic intermediate from preclavulone-A to clavulones, and a possible biogenetic pathway via 3 is proposed.

This paper describes the discovery and total synthesis of bioactive marine natural products conducted in our laboratory. Clavulone, chlorovulone, bromovulone, and iodovulone are antitumor marine prostanoids isolated from the Okinawan soft coral Clavularia viridis. The synthesis of clavulone and chlorovulone was achieved from chiral 4-hydroxy-2-cyclopentenone. Marine prostanoid punaglandins 3 and 4 were synthesized via similar methodology. The chemical structures of punaglandins 3 and 4 were revised by these syntheses. Dollaberane-type diterpenoid stolonidiol and claenone were isolated from Okinawan soft coral Clavularia sp. Stolonidiol showed potent choline acetyltransferase-inducible activity in cultured basal forebrain cells. The synthesis of stolondiol and claenone was conducted via sequential Michael reaction and retro-aldol reaction. Aragusterols, isolated from the Okinawan marine sponge Xestospongia sp., are structurally unique steroids possessing a rare 26,27-cyclo structure in the side chain. Aragusterols express potent in vivo antitumor activity against L1210 leukemia in mice. The synthesis of aragusterols was carried out via steroselective construction of the side chain and stereocontrolled coupling reaction with the steroid skeleton. Kalihinane-type diterpenoid kalihinol A, isolated by Scheuer, has remarkable in vitro antimalarial activity. The absolute configuration of kalihinol A was determined by applying the CD exciton chiral method. Synthesis of kalihinene X, a kalihinane-type diterpenoid, was achieved. This synthesis involves the regioselective coupling reaction of carbanion of alkyl sulfone with epoxyalcohol and construction of cis-decalin by an intramolecular Diels-Alder reaction.

Prostaglandins A1 (PGA1), A2, B1, B2, E1, E2, F1α, F2α, and 19 esterified natural fatty acids were tested as effectors of beef liver glutamate dehydrogenase (L-glutamate: NAD(P)+, oxidoreductase [deaminating], EC 1.4.1.3). All prostaglandins tested are found to activate the enzyme initially, but only PGA2>PGB2≥PGA1 cause a subsequent time-dependent loss (not inhibition) of NADH oxidation activity. Both PGA1 and PGA2 desensitize glutamate dehydrogenase to allosteric activation by ADP, whereas PGA2 and PGB2 desensitize to allosteric inactivation by GTP. Preincubation of enzyme with diethylstilbestrol prevents the initial activation by the PG. Of the methyl esters, only prostaglandin precursors inactivated the enzyme. Simultaneous desensitization to the ADP and GTP allosteric effects resulted. Multiple esterification to glycerol or phospholipids enhanced the action of linoleoyl and diminished the action of linolenoyl chains. Preincubation of the PGA with glutathione or cysteine prevents the inactivation; i.e., the sulfhydryl binding region of the prostaglandin must be free for enzyme to be inactivated. Sulfhydryl reagents also protect the enzyme from the effects of the unsaturated acyl chains, and pHMB mimics acyl protection against GTP allosteric inactivation. Where the lipid effector is active against sulfhydryl groups, the desensitizations to the ADP and GTP allosteric effectors are reciprocal. The initial activation, subsequent inactivation and desensitization to ADP and GTP are all characteristic of binding in the estrogen-specific effector site, suggesting this site as the target for PG and acyl action. In the PGA2 activation, the effect is found to be amplified by the cooperativity of the enzyme at 1 PG molecule/6 molecules of GDH. We conclude from the action of the PG and structural analogs that the initial activation of glutamate dehydrogenase is caused by α,β-unsaturated monoketo cyclopental structures. GTP inhibition is blocked primarily by diketo structures which eventually inactivate the enzyme. ADP activation is blocked by sulfhydryl binding of the unsaturated cyclopental keto structure of the PG. Appearance of a 270 nm absorbance simultaneous to the acyl effects on the enzyme suggests that conjugated unsaturations are responsible for the precursor's qualitatively similar action to that of the PG.

Field desorption (FD) mass spectrometry was applied to the determination of prostaglandin E2 (PGE2) in urine. Studies on synthetic compounds showed that methyl esters are stable under FD mass spectrometric conditions. The ester of PGE2 gives rise to protonated molecular ions and fragments due to the elimination of water and the side chains C8H14O and C8H12O2. This behaviour enabled its determination in the nanogram per millilitre range.

SUMMARY Urinary immunoreactive PGA and PGE, plasma and urinary aldosterone, and plasma renin activity (PRA) were determined in eleven control subjects and four patients with diabetic hyporeninaemic hypoaldosteronism (HH) before and during 4 days of sodium chloride restriction and frusemide administration. Aldosterone and PRA increased steadily in control subjects, but not in patients with HH. Increases in urinary PGA and PGE were observed during volume depletion. The basal levels and increases observed were comparable in both groups. The apparently normal stimulation of PGA and PGE in subjects with diabetic HH suggests that this syndrome is not associated with abnormal prostaglandin metabolism, despite the fact that drug-induced abnormalities of the latter may precipitate or aggravate the clinical syndrome in susceptible individuals. The increase in PGA and PGE following frusemide treatment and salt depletion supports the possibility of a relationship between renal prostaglandin metabolism, frusemide-induced natriuresis and/or renin secretion. While the nature of this relationship remains obscure, the increases in PGA and PGE in the absence of increases in renin-angiotensin levels in subjects with HH suggests that these changes are not due to activation of the renin-angiotensin system.

The actions of prostaglandins (PG) on cAMP in dispersed chief cells from guinea pig stomach were examined and compared to the actions of these agents on pepsinogen secretion. Maximal concentrations of A, B, or E prostaglandins caused a 2-5-fold increase in pepsinogen secretion and cellular cAMP. The relative order of potency for these actions was PGEs greater than PGAs greater than PGBs. Detection of prostaglandin-induced changes in cAMP was enhanced by adding a phosphodiesterase inhibitor to the incubation solution. The time courses for the effects of prostaglandins on pepsinogen secretion and cAMP were similar. With PGE1 an increase in cAMP and pepsinogen secretion was detected by 1 min and was maximal by 7.5 min. Although significant increases in cAMP were detected with a ten-fold lower concentration of PGEs than PGAs, a maximal increase in cAMP was observed with the same concentration, 30 microM, of either agent. These data indicate that prostaglandins that stimulate pepsinogen secretion increase cAMP in dispersed chief cells. However, comparison of the dose-response curves for the actions of prostaglandins on pepsinogen secretion and cAMP revealed that detectable increases in cAMP occurred with concentrations of these agents that were about ten-fold greater than those needed to stimulate pepsinogen secretion. Therefore, although the similarity in the kinetics and relative potencies of prostaglandin-induced changes in cAMP and enzyme secretion provides further evidence that changes in cAMP play a role in the mediation of prostaglandin-induced pepsinogen secretion, the present data suggest the involvement of a cellular messenger in addition to cAMP.