Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P61278 (somatostatin)
 22,083 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of serotonin (5-HT) on gonadotropin and growth hormone release from perifused goldfish (Carassius auratus, L.) pituitary glands were studied. Serotonin, at micromolar concentrations, caused a dose-related release of gonadotropin and an inhibition of growth hormone release in pituitaries from goldfish at different sexual stages. At lower concentrations 5-HT continued to inhibit growth hormone release, but had no effects on gonadotropin release. The stimulatory effects of 5-HT on gonadotropin release could be blocked by ketanserin and cyproheptadine; however, these two antagonists had no effects on 5-HT inhibition of growth hormone release. Perifusion with melatonin had no effect on the release of gonadotropin or growth hormone release. These results demonstrate that 5-HT has a stimulatory effect on gonadotropin secretion, probably through a 5-HT2 receptor type, and an inhibitory effect on growth hormone through an unidentified receptor type. We hypothesize that the effects on gonadotropin release are due to direct actions on gonadotrophs, whereas the effects on growth hormone release may be due to stimulation of somatostatin release from neurosecretory terminals in the pituitary.
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PMID:Effects of serotonin on gonadotropin and growth hormone release from in vitro perifused goldfish pituitary fragments. 187 80

Patients with midgut carcinoids undergoing surgical resection or ischemic treatment of hepatic metastases by embolization are at risk for development of carcinoid crises due to release of hormonally active tumor products. Eight such patients were treated on nine separate occasions with increasing subcutaneous doses of a synthetic somatostatin analogue (SMS 201-995) 4 days prior to surgery or hepatic arterial embolization. The patients were tested by pentagastrin provocation and simultaneous measurement of serotonin (5-HT) levels in peripheral blood before and after prophylactic treatment, to evaluate the efficacy of SMS 201-995. The provoked release of 5-HT was markedly diminished, and the basal levels of 5-HT were markedly reduced in patients with high initial levels. During surgery or embolization both SMS 201-995, as well as ketanserin, a 5-HT2 receptor blocker, were given. With this combined treatment all patients were hemodynamically stable during surgery or embolization. During embolization the arterial levels of 5-HT increased only moderately, while urinary excretion of 5-hydroxyindoleacetic acid remained unchanged despite a proven adequate embolization. Two patients were operated on without previous treatment with SMS 201-995; both developed severe crises at induction of anesthesia, but IV SMS 201-995 rapidly reversed the bronchoconstriction and facial flush and gradually restored arterial blood pressure, even though cardiac output remained depressed for a prolonged period. The crisis reaction correlated well with high circulating levels of 5-HT, but after treatment with SMS 201-995 these levels were still high.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:SMS 201-995 and provocation tests in preparation of patients with carcinoids for surgery or hepatic arterial embolization. 246 65

The role of 5-hydroxytryptamine (5-HT) in the acute regulation of the rat brain somatostatin (SS) receptor-effector system and somatostatin-like immunoreactivity (SSLI) content was examined. 5-HT administered i.c.v. in a volume of 10 microliters at a dose of 0.5 microgram (pH 3.4) increased the SSLI concentration at 60 min in the Wistar rat frontoparietal cortex and hippocampus (60%, P < 0.05; 72%, P < 0.01; respectively). These changes were associated with a significant increase in the total number of specific SS receptors in the frontoparietal cortex (24%, P < 0.05) and hippocampus (20%, P < 0.05), without changes in the affinity constant as compared with the control group. No significant differences were seen in the basal and forskolin (FK)-stimulated adenylate cyclase (AC) activities in both brain areas of 5-HT-treated rats when compared to the control group. The capacity of SS to inhibit the FK-stimulated AC activity in the frontoparietal cortex and hippocampus of 5-HT-treated rats was lower than in the control groups. The ability of the stable GTP analogue 5'-guanylylimidodiphosphate (Gpp(NH)p) to inhibit FK-stimulated AC activity in frontoparietal cortical and hippocampal membranes was markedly decreased in 5-HT-treated rats. To determine if the above-mentioned changes were related to the 5-HT activation of central 5-HT1 and 5-HT2 receptors, a non-selective 5-HT1 and 5-HT2 receptor antagonist, methysergide, was administered 60 min before the 5-HT injection. Pretreatment with methysergide (5 mg/kg i.p. in a volume of 400 microliters) prevented the 5-HT-induced changes in the SS receptor-effector system and in SSLI levels in both brain areas. Methysergide alone had no observable effect on the somatostatinergic system. These results suggest that the frontoparietal cortical and hippocampal somatostatinergic system can be regulated by 5-HT receptors.
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PMID:Modulation by 5-hydroxytryptamine of the somatostatin receptor-effector system and somatostatin levels in rat brain. 873 59