Effect of 5-hydroxytryptamine on blood glucose and cyclic AMP in the rat.
The effects of 5-hydroxytryptamine (5-HT) on plasma cyclic AMP (cAMP) and glucose concentrations were studied in rats in vivo. 5-HT injected i.p. increased plasma cAMP and glucose. Injections of propranolol, hexamethonium, and cyproheptadine inhibited the 5-HT-induced increase in glucose but not in cAMP. Atropine did not inhibit the action of 5-HT. These effects of 5-HT were not seen in adrenomedullectomized rats, and 5-HT did not elevate the concentration of plasma cAMP in anti-glucagon antiserum-injected rats. These results confirm the previously reported finding that 5-HT-induced increase in blood glucose is mediated via adrenaline released from adrenal medulla by 5-HT and suggest that the increase in plasma cAMP, induced by 5-HT, is due to glucagon released by an unknown factor, or factors other than adrenaline released from the adrenal medulla by 5-HT.
D000313:Adrenal Medulla / Q000502:physiology; D000818:Animals; D000906:Antibodies; D001786:Blood Glucose / Q000378:metabolism*; D000242:Cyclic AMP / Q000097:blood*; D003533:Cyproheptadine / Q000494:pharmacology; D004837:Epinephrine / Q000494:pharmacology; D005934:Glucagon / Q000276:immunology; D006584:Hexamethonium Compounds / Q000494:pharmacology; D007274:Injections, Intraperitoneal; D008297:Male; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D012701:Serotonin / Q000008:administration & dosage / Q000494:pharmacology*
D000906:Antibodies; D001786:Blood Glucose; D006584:Hexamethonium Compounds; D003533:Cyproheptadine; D012701:Serotonin; D005934:Glucagon; D011433:Propranolol; D000242:Cyclic AMP; D004837:Epinephrine