Inhibitory effects of tryptamine on tolbutamide-induced hypoglycemia in mice: Mediation by 5-HT receptors

摘要

Effects of tryptamine on tolbutamide-induced hypoglycemia were investigated in mice. Tryptamine significantly inhibited hypoglycemia elicited by tolbutamide. The inhibitory effects of tryptamine were strongly blocked by the 5-HT1and 5-HT2receptor antagonist methysergide and the 5-HT2receptor antagonist ketanserin, while the 5-HT3receptor antagonist ICS 205–930 was without effect. Tryptamine induced hyperglucagonemia in tolbutamide-treated mice, and this effect elicited by tryptamine was strongly inhibited by the 5-HT2receptor antagonist ketanserin. These results suggest that the inhibitory effects of tryptamine on tolbutamide-induced hypoglycemia are mediated by 5-HT2receptors and that tryptamine is involved in glucagon releas