Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present study was performed to examine the effect of the cyclo-oxygenase inhibitor, indomethacin, and that of various prostaglandins on the release of vasopressin and beta-endorphin-like immunoreactivity (beta-EI) from the rat neurointermediate lobe of the hypophysis, which was superfused in vitro. Indomethacin (2.8 and 28 mumol/l) changed neither basal secretion of vasopressin nor that evoked by electrical stimulation, whereas the resting release of beta-EI was enhanced by indomethacin (28 mumol/l). Prostaglandin (PG) E2 did not influence resting release of vasopressin but markedly inhibited (by about 50%) electrically induced release of vasopressin (least effective concentration: 300 nmol/l) as well as spontaneous secretion of beta-EI (least effective concentration: 100 nmol/l) in the presence of indomethacin (28 mumol/l). Prostaglandin F2 alpha (5 mumol/l) also inhibited the evoked release of vasopressin, whereas PGD2 (5 mumol/l) did not. Prostaglandin F2 alpha (5 mumol/l), D2 and I2 (1.5 mumol/l each) produced no effects on beta-EI release. As observed in the neurohypophysis, PGE2 inhibited the electrically induced release of vasopressin from the medial basal hypothalamus in vitro. We conclude that prostaglandins (especially PGE2) can inhibit (1) the stimulated release of vasopressin when acting on vasopressin-containing nerve terminals of either neurosecretory system (neurohypophysis, median eminence region), and (2) the secretion of beta-EI and, as can be inferred, alpha-MSH, by a direct action on intermediate lobe cells.
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PMID:Inhibition by prostaglandin E2 of the release of vasopressin and beta-endorphin from rat pituitary neurointermediate lobe or medial basal hypothalamus in vitro. 316 Aug 2

Human fetal adrenal (HFA) tissue was maintained in organ culture to evaluate the biosynthesis of prostaglandins and hormonal regulation of prostaglandin formation by this tissue. The HFA tissue secreted substantial amounts of prostaglandin E(2), prostaglandin F(2alpha), 13,14-dihydro-15-ketoprostaglandin F(2alpha), 6-ketoprostaglandin F(1alpha), and thromboxane B(2); secretion of prostaglandin D(2) could not be demonstrated. Prostaglandin biosynthesis in HFA tissue was inhibited in a time-dependent manner by corticotropin (ACTH; 0.4 muM); by the fourth day of culture, the extent of inhibition of biosynthesis of each prostaglandin was 60-90%. Progesterone (1 muM), cortisol (1 muM), and dexamethasone (1 muM) inhibited prostaglandin biosynthesis whereas estradiol (1 muM) did not. Of the compounds tested for inhibitory activity, dexamethasone was the most potent. An inhibitor of 11beta-hydroxylase activity (metyrapone; 0.1 mM) effectively eliminated the inhibition of prostaglandin biosynthesis caused by corticotropin and progesterone. Metyrapone treatment alone caused a 3-fold increase in prostaglandin biosynthesis by fetal adrenal tissues. Similar stimulatory effects resulted from treatment with inhibitors of (i) 3beta-hydroxysteroid dehydrogenase (cyanoketone; 15 muM), (ii) steroid 17alpha-hydroxylase (SU 10603; 19 muM), and (iii) cholesterol side-chain cleavage (aminoglutethimide; 1 mM). Inhibition of prostaglandin biosynthesis by dexamethasone in the presence or absence of metyrapone was concentration dependent and 50% inhibition could be demonstrated at 1 nM. A competitive inhibitor of the binding of glucocorticosteroids to cytoplasmic receptors (cortisol 21-mesylate; 1 muM) significantly reduced the inhibition of prostaglandin biosynthesis effected by dexamethasone (10 nM). These findings suggest that prostaglandin biosynthesis in the HFA gland is regulated by endogenously synthesized glucocorticosteroids, the actions of which are mediated by a glucocorticosteroid receptor. Such glucocorticosteroids induce the synthesis of a substance that inhibits prostaglandin biosynthesis.
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PMID:Prostaglandin biosynthesis in the human fetal adrenal gland: regulation by glucocorticosteroids. 629 39

Prostaglandin F(2alpha) (PGF(2alpha)), represses ovarian steroidogenesis and initiates parturition in mammals but its impact on adrenal gland is unknown. Prostaglandins biosynthesis depends on the sequential action of upstream cyclooxygenases (COX) and terminal synthases but no PGF(2alpha) synthases (PGFS) were functionally identified in mammalian cells. In vitro, the most efficient mammalian PGFS belong to aldo-keto reductase 1B (AKR1B) family. The adrenal gland is a major site of AKR1B expression in both human (AKR1B1) and mouse (AKR1B3, AKR1B7). Thus, we examined the PGF(2alpha) biosynthetic pathway and its functional impact on both cortical and medullary zones. Both compartments produced PGF(2alpha) but expressed different biosynthetic isozymes. In chromaffin cells, PGF(2alpha) secretion appeared constitutive and correlated to continuous expression of COX1 and AKR1B3. In steroidogenic cells, PGF(2alpha) secretion was stimulated by adrenocorticotropic hormone (ACTH) and correlated to ACTH-responsiveness of both COX2 and AKR1B7/B1. The pivotal role of AKR1B7 in ACTH-induced PGF(2alpha) release and functional coupling with COX2 was demonstrated using over- and down-expression in cell lines. PGF(2alpha) receptor was only detected in chromaffin cells, making medulla the primary target of PGF(2alpha) action. By comparing PGF(2alpha)-responsiveness of isolated cells and whole adrenal cultures, we demonstrated that PGF(2alpha) repressed glucocorticoid secretion by an indirect mechanism involving a decrease in catecholamine release which in turn decreased adrenal steroidogenesis. PGF(2alpha) may be regarded as a negative autocrine/paracrine regulator within a novel intra-adrenal feedback loop. The coordinated cell-specific regulation of COX2 and AKR1B7 ensures the generation of this stress-induced corticostatic signal.
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PMID:Aldo keto reductase 1B7 and prostaglandin F2alpha are regulators of adrenal endocrine functions. 1980 95

This study shows that prostaglandins in human FM55 melanoma cells and epidermal melanocytes are produced by COX-1. Prostaglandin production in FM55 melanoma cells was unrelated to that of melanin suggesting that the two processes can occur independently. Alpha-melanocyte-stimulating hormone, which had no effect on melanin production in FM55 cells, stimulated PGD(2) production in these cells without affecting PGE(2). While cAMP pathways may be involved in regulating PGD(2) production, our results suggest that alpha-MSH acts independently of cAMP, possibly by regulating the activity of lipocalin-type PGD synthase. This alpha-MSH-mediated effect may be associated with its role as an immune modulator.
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PMID:Prostaglandin D production in FM55 melanoma cells is regulated by alpha-melanocyte-stimulating hormone and is not related to melanin production. 2048 20