The inhibitory action of 5-hydroxytryptamine on gastric secretory function in rats.
The inhibitory action of 5-hydroxytryptamine (5-HT) on gastric function was studied in vagotomized rats. 5-HT (0.6, 1 or 5 mgkg-1, s.c.) dose-dependently reduced gastric acid secretion evoked by histamine, pentagastrin or methacholine. Pepsin secretion induced by pentagastrin or methacholine was also depressed by 5-HT. Basal secretion of both acid and pepsin was not significantly affected by any of the three 5-HT doses. Indomethacin pretreatment, which significantly decreased gastric mucosal prostaglandin E2 content, did not modify the inhibitory effects of 5-HT on histamine-induced acid secretion, nor did phentolamine or propranolol. This study suggests that 5-HT inhibits gastric secretory function through mechanisms other than by sympathetic influence or increased prostaglandin synthesis. The inhibitory action appears not to be vagus-dependent. Other mechanisms of action are discussed.
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D002118:Calcium / Q000097:blood; D004347:Drug Interactions; D005753:Gastric Mucosa / Q000187:drug effects* / Q000378:metabolism; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D010477:Perfusion; D010646:Phentolamine / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D011458:Prostaglandins E / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000097:blood / Q000494:pharmacology*
D001786:Blood Glucose; D011458:Prostaglandins E; D012701:Serotonin; D011433:Propranolol; D002118:Calcium; D007213:Indomethacin; D010646:Phentolamine