Prostaglandins, leukotrienes, and medicine最新文献

{"title":"Stimulation of aggregation and thromboxane A2 formation of human platelets by hypoxia","authors":"K. Pönicke ,&nbsp;R. Sternitzky ,&nbsp;H.-J. Mest","doi":"10.1016/0262-1746(87)90096-5","DOIUrl":"10.1016/0262-1746(87)90096-5","url":null,"abstract":"<div><p>The influence of hypoxia on the spontaneous platelet aggregation (SPA) and thromboxane formation was studied. The analysis of aggregation curve was carried out according to Breddin.</p><p>The hypoxia enhanced the aggregayility from Q₂norm = 2.46 ±0.40 (normoxia) to Q₂hyp = 4.39±0.39 (hypoxia), n = 52, p &lt; 0.001. 10 samples of those showed no SPA under equilibration with air but the hypoxic stimulus provoked SPA (Q₂norm = 0, Q₂hyp = 1.19±60, n = 10, p &lt; 0.001).</p><p>When the results were arranged according to the degree of the stimulation of SPA, two groups could be separated with low and high response to hypoxic.</p><p>The hypoxia caused also an augmentation of the TXB₂ level in comparison to normoxia. The stronger enhancement of the TXB₂ formation during the incubation under hypoxic conditions was independent of the fact whether SPA took place or not.</p><p>The present study suggests that hypoxic conditions alone may be a reason for a stimulated TXA₂ formation of the platelets and that the enhanced TXA2 formation caused by hypoxic is possibly inducing or reinforcing the SPA.</p></div>","PeriodicalId":20720,"journal":{"name":"Prostaglandins, leukotrienes, and medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1987-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0262-1746(87)90096-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14603345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inhibition of platelet aggregation and reduced formation of thromboxane and lipoxygenase products in platelets by oil of cloves","authors":"K.C. Srivastava,&nbsp;Ulla Justesen","doi":"10.1016/0262-1746(87)90092-8","DOIUrl":"10.1016/0262-1746(87)90092-8","url":null,"abstract":"<div><p>Oil of cloves (OC) was found to be a potent inhibitor of platelet aggregation induced by arachidonic acid (AA), collagen and epinephrine; in this respect it was most effective against AA-induced aggregation. Inhibition of aggregation by OC seems to be mediated through a reduced formation of thromboxane as indicated by the following experimental evidence. (i) OC inhibited TxB₂ formation in intact as well as lysed platelet preparations from added arachidonate, and (ii) it inhibited the formation of TxB₂ from AA-labelled platelets after activation with Ca²⁺-ionophore A23187. The formation of lipoxygenase derived products was dependent on the concentration of OC used; at its lower concentration their amounts increased but this was found to be reversed at higher concentrations. At all concentrations thromboxane was decreased with a concomitant increase in unused AA.</p></div>","PeriodicalId":20720,"journal":{"name":"Prostaglandins, leukotrienes, and medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1987-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0262-1746(87)90092-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14250038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of steroids on renal nad+-dependent 15-hydroxy-prostaglandin dehydrogenase activity in ovariectomized rats","authors":"Wen-Chang Chang","doi":"10.1016/0262-1746(87)90094-1","DOIUrl":"10.1016/0262-1746(87)90094-1","url":null,"abstract":"<div><p>It has been suggested that the circulating prostacyclin in primarily inactivated by renal NAD+-dependent 15-hydroxyprostaglandin dehydrogenase. Changes in the renal enzyme activity in response to hormones were studied. The renal 15-hydroxyprostaglandin dehydrogenase activity in female rats was lower than that in male rats, and was significantly increased by ovariectomy. The effect of sex steroids on the renal enzyme activity was then studied in ovariectomized rats. Estradiol administration induced a significant decrease in the renal enzyme activity, while testosterone did not show any significant effect. Kinetic parameters for the renal enzyme from control and estradiol-treated groups were compared. An identical apparent Km for prostaglandin E₂ was obtained for the enzyme from both groups. Vmax in the treated group was progressively decreased. The enzyme from both groups decayed at the same rate. The results indicated that estradiol might be the major endogenous sex steroid regulating the renal NAD+-dependent 15-hydroxyprostaglandin dehydrogenase activity, and the inhibitory effect of estradiol on the renal enzyme might be due to the inhibition of the enzyme biosynthesis.</p></div>","PeriodicalId":20720,"journal":{"name":"Prostaglandins, leukotrienes, and medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1987-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0262-1746(87)90094-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14601646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prostaglandin output from and the spontaneous inotropism of uterine horns isolated from underfed rats at different stages of the sex cycle. smooth muscle contractile influences of indomethacin and of methoxamine","authors":"A.B.F. Sterin,&nbsp;A. Goldraij,&nbsp;M.A.F. Gimeno,&nbsp;A.L. Gimeno","doi":"10.1016/0262-1746(87)90095-3","DOIUrl":"10.1016/0262-1746(87)90095-3","url":null,"abstract":"<div><p>The influences of a period of 15 days of restricted diet (50% of the normal food intake) in rats sacrificed at different stages of the sex cycle (proestrus, estrus, metestrus and diestrus), were explored on: (1) the magnitude of uterine spontaneous phasic contractions (isometric developed tension= IDT); (2) the release of prostaglandins (PGs) F_2α and E₂; from the uterus and (3) the myometrial inotropic responses evoked by methoxamine and indomethacin. At estrus and at proestrus, preparations from restricted diet rats exhibited greater initial (postisolation) IDT and better contractile constancy during 60 min than did uteri from normal fed rats. This enhanced contractile constancy, but not that of preparations from control fed rats, was prevented by incubation “in vitro” with indomethacin (10⁻⁶M). At metestrus and at diestrus, uteri from normal fed rats presented higher initial levels of IDT and even more sustained contractile constancy than at estrus or at proestrus. Moreover, contractile profiles remained unaltered following the dietary restriction and the presence of indomethacin evoked similar negative inotropic actions in both experimental groups (fed and underfed). Dose-response curves for methoxamine documented its possitive, but different, inotropic actions in the two groups and at the four periods of the estrous cycle. Indeed, in the underfed group at estrus and at proestrous, dose-response curves for methoxamine were shifted to the left of those in fed controls,a situation prevented by indomethacin (10-6M); whereas at metestrus and at diestrus, no differences in the inotropic reactivity towards methoxamine between the two experimental groups, were detected. On the other hand, indomethacin shifted to the right dose-response curves for the agonist, both in preparations from normal fed and from restricted diet rats. The generation and release of PGF_2α and of PGE₂ were explored under normal and restricted diet conditions, both at estrus and at diestrus. Following the dietary restriction, the output of PGE₂ from estrous uteri was augmented in comparison to controls, whilst the release of PGF_2α was not affected. At diestrus, dietary restriction failed to alter the uterine output of either one of these PGs. Results suggest that a greater generation and release of PGE₂, following underfeeding, appears to subserve the increased spontaneous motility and the greater sensitivity of the rat uterus for — adrenoreceptor agonists.</p></div>","PeriodicalId":20720,"journal":{"name":"Prostaglandins, leukotrienes, and medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1987-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0262-1746(87)90095-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14603344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of some beta blockers (pindolol, atenolol, timolol and metoprolol) on aggregation and arachidonic acid metabolism in human platelets","authors":"K.C. Srivastava","doi":"10.1016/0262-1746(87)90099-0","DOIUrl":"10.1016/0262-1746(87)90099-0","url":null,"abstract":"<div><p>The effects of four beta-adrenoceptor blocking agents on platelet aggregation, formation of thromboxane from exogenous arachidonic acid (AA) in platelets, on AA incorporation in platelet phospholipids, and on platelet phospholipase activity were studied. Of the four drugs pindolol inhibited thromboxane formation in a dose-related (0.25–1.0 mM) manner apparently by exerting its influence at the cyclooxygenase (CO) level. This drug also inhibited aggregation induced by AA, collagen, epinephrine and ADP. Atenolol and metoprolol though not showing inhibition of AA-induced aggregation did inhibit collagen- and ADP-induced aggregation; metoprolol reversed ADP-induced aggregation, and abolished second phase of epinephrine-induced aggregation. Timolol did not inhibit aggregation induced by all the aggregating agents. Atenolol inhibited (by ca. 1096) TxB₂ formation in platelets from exagenous as well as endogenous AA at rather high concentrations (1.0 mM). Metoprolol and Tmolol did not do so. The observations reported here can be best explained by taking into account the membrane stabilizing effects and lipophilic properties of the drugs.</p></div>","PeriodicalId":20720,"journal":{"name":"Prostaglandins, leukotrienes, and medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1987-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0262-1746(87)90099-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14026420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prostaglandin production by human myometrium, uterine cervix and leiomyoma","authors":"Masatoshi Yamaguchi,&nbsp;Norimasa Mori","doi":"10.1016/0262-1746(87)90102-8","DOIUrl":"10.1016/0262-1746(87)90102-8","url":null,"abstract":"<div><p>In order to investigate prostacyclin production by human myometrium, uterine cervix and leiomyoma, slices of each tissue were incubated.The 6-keto prostaglandin F_1α concentration of the incubation medium was measured by radioimmunoassay. The serosal and endometrial sides of myometrium produce 6-keto prostaglandin F_1α, with no significant difference in production between the two sides. The 6-keto PGF_1α production of leiomyoma was significantly higher than that of myometrium. Our results suggest that human myometrium and leiomyoma produce prostacyclin regardless of vascularization.</p></div>","PeriodicalId":20720,"journal":{"name":"Prostaglandins, leukotrienes, and medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1987-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0262-1746(87)90102-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14601645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Is there a prostaglandin involvement in the positive inotropic action of histamine in isolated pregnant rat uterus, apparently mediated via H1-receptors activation?","authors":"M. Viggiano,&nbsp;A.M. Franchi,&nbsp;G. Dveksler,&nbsp;M.F. Gimeno,&nbsp;A.L. Gimeno","doi":"10.1016/0262-1746(87)90118-1","DOIUrl":"10.1016/0262-1746(87)90118-1","url":null,"abstract":"<div><p>Cumulative dose-response curves for histamine induced responses in mesometrial (ME) and antimesometrial (AME) regions of uterine horns isolated from rats at 7th, 16th and 22nd days of pregnancy, were constructed. Histamine inhibited, in dose-related fashion, the isometric developed tension in ME and AME strips obtained at the 7th day of pregnancy, an action antagonized by cimetidine (10⁻⁴–10⁻⁵M). On the contrary, at the 16th and 22nd days, histamine (10⁻⁵–10⁻³M), stimulated spontaneous contractions in the ME region but had no effect in the AME segment. Although histamine and SKF-71481-A₂,aH₁-receptor agonist, both at 10⁻⁴M, enhanced similarly ME inotropism at the 16th and at 22nd days of pregnancy, the positive contractile action of histamine was greater at the 16th than at the 22nd day. Moreover, cumulative dose-response curves for histamine and SKF-71481-A₂ in the ME region of uteri isolated at the 16th day of gestation, showed that both agonists have approximately the same inotropic potency and efficacy. On the other hand, pyrilamine (at 10⁻⁴M, but not at 10⁻⁵M),aH₁-receptor antagonist, shifted to the right the dose-response curve for histamine in ME strips from uteri at the 16th day of pregnancy and attenuated significantly, the magnitude of the positiue inotropism evoked by the amine. Similar findings were observed in the presence of chlorpheniramine (at 10⁻⁶M) another H₁-receptor blacker. In addition, the positive uterine inotropism evoked by histamine in the ME region of preparations isolated at the 16th day of pregnancy, was significantly reduced by an antagonist of phospholipase A₂ (mepacrine, 10⁻⁴M) as well as by acetylsalicylic acid (ASA at 10⁻⁴M), an inhibitor of cyclooxygenase. Results also indicate that the excitatory uterine inotrpism elicited by the agonistic amine in ME strips isolated from rats at the 16 th day of pregnancy, was coincident with an enhanced release of prostaglandins (PGs) E₂ and F₂ α, but not of PGE₁ and that both augmenting actions of histamine were antagonized by histamine H₁ receptor-blockers, namely pyrilamine (mepyramine or chlorpheniramine. Results suggest that histamine at early pregnancy diminished myometrial inotropism via its interaction with H₂-receptors, whereas from mid pregnancy up to the moment of parturition it evokes contractile stimulation, most likely due to the activation of H₁-receptor located at the mesometrial region of rat uterine horns. Altogether the present data suggest that after mid pregnancy, histamine acts at the ME region of the uterus through a cascade of influences: (a) activation of H₁ receptors, (b) stimulation of phospholipase A₂ (via an increased permeability of calcium ions?), which catalyzes the release of ","PeriodicalId":20720,"journal":{"name":"Prostaglandins, leukotrienes, and medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1987-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0262-1746(87)90118-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14601002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prostacyclin synthesis stimulating plasma factor in patients with peripheral vascular disease","authors":"Eva Strobl-Jäger ,&nbsp;P. Fitscha ,&nbsp;J. Kaliman ,&nbsp;H. Sinzinger ,&nbsp;B.A. Peskar","doi":"10.1016/0262-1746(87)90120-X","DOIUrl":"10.1016/0262-1746(87)90120-X","url":null,"abstract":"<div><p>Human plasma contains a factor capable of stimulating vascular prostacyclin generation even in atherosclerotic vessels with minimal in-vitro capacity for PGI2-synthesis. The activity of this prostacyclin stimulating plasma factor (PSPF) has been reported to be elevated in renal failure and hepatic coma. We are not aware of any data as to whether this PSPF plays a role in maintaining hemostatic balance in patients with peripheral vascular lesions. Therefore, we examined 62 patients with peripheral vascular disease (PVD). This study group was subdivided into normo- and hyperlipemic subjects, patients with and without maturity onset diabetes, and plasma β-thromboglobulin levels higher and lower than 50 ng/ml. 10 healthy sex and age matched persons served as controls. Vascular prostacyclin formation was studied in vitro after incubation of the patients' plasma and a buffer control with various tissue samples (human femoral artery, rat abdominal and thoracic aorta of healthy and of streptozotocin induced diabetic animals, swine endothelial layer and remaining tissue (media and adventitia) and cultured endothelial (EC) and smooth muscle cells (SMC) of minipig arota. In addition, 6-oxo-PGFlα formation by cultured EC and SMC (minipig aorta source) after incubation with tris HCl-buffer or plasma were estimated by means of specific radioimmunoassays. In general, tissue samples and cells incubated in plasma exhibit a marked increase of in-vitro PGI2-formation as compared to buffer. No difference could be found between PSPF of CHD-patients and healthy controls. Similar findings were obtained using incubated vascular tissue and cultured cells by means of the bioassay and specific RIA, respectively.</p><p>These findings indicate that the PSPF does not seem to be of any clinical relevance in hemostatic regulation in patients with advanced atherosclerosis.</p></div>","PeriodicalId":20720,"journal":{"name":"Prostaglandins, leukotrienes, and medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1987-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0262-1746(87)90120-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14093722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Amniotic fluid prostaglandins F2α and E2 , measured at artificial rupture of the membranes”, predict the subsequent progress of labour","authors":"H.A. Leaver ,&nbsp;H.D. MacPherson ,&nbsp;D.J.R. Hutchon ,&nbsp;S.E. Scotland","doi":"10.1016/0262-1746(87)90113-2","DOIUrl":"10.1016/0262-1746(87)90113-2","url":null,"abstract":"<div><p>Prostaglandin F_2α and E₂ concentrations in the amniotic fluid and fetal membranes of 35 patients was analysed, in order to investigate differences in prostaglandin synthesis in parous and nulliparous women, and to find whether women who subsequently required oxytocin to accelerate labour, showed any difference in intrauterine prostaglandin concentrations. Significantly less PGF_2α was detected in the amniotic fluid of women who required oxytocin, and fetal membrane PGE₂ was significantly lower in these women at delivery. Differences in PGE₂ and PGF_2α in parous and nulliparous women were less mar ed. Amniotic fluid levels of PGF₂ at Artificial Rupture of the Membranes (ARM), and the ratio of PGF_2α/PGE₂ at ARM, were prognostic for the subsequent progression of labour.</p></div>","PeriodicalId":20720,"journal":{"name":"Prostaglandins, leukotrienes, and medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1987-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0262-1746(87)90113-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14601000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of alpha-fetoprotrein and indomethacin on arachidonic acid metabolism in P388D1 macrophages : Role of leuxotrienes","authors":"Claude Aussel,&nbsp;Max Fehlmann","doi":"10.1016/0262-1746(87)90121-1","DOIUrl":"10.1016/0262-1746(87)90121-1","url":null,"abstract":"<div><p>Alpha-fetoprotein (AFP),is able to modify arachidonic acid metabolism In P388DI macrophage - like cells. AFP has been shown to induce mobilization of arachidonic acid and consequently an enhanced production of leukotrienes.The action of AFP on the cyclooxygenase pathway appears, however, more complex, as this protein simultaneously decreases the total amount of cyclooxygenase products and raises the production of PGE2, 6-keto-PGF1α and to a lesser extent of thromboxane B2. On the other hand, indomethacin abolishes the synthesis of PGE2 but has no effect on 6-keto-PGFlα and thromboxane B2. Indomethacin used in combination with AFP partly loses its inhibiting effect on PGE2 synthesis and paradoxically leads to a “superactivation” of P388D1 cells demonstrated by a very high arachidonic acid mobilization, an enhancement of both leukotriene synthesis and cyclooxygenase activity. Evidence for a binding of indomethacin to AFP was obtained that partly explains these results. In addition, it is shown that the effects of AFP and AFP+Indomethacin on cyclooxygenase activity might be explained by the endogenous synthesis of leukotrienes.</p></div>","PeriodicalId":20720,"journal":{"name":"Prostaglandins, leukotrienes, and medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1987-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0262-1746(87)90121-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13589815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}