Effects of the 5-HT2A receptor agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) on plasma glucose and glucagon levels of rats

Effects of the 5-hydroxytryptamine (5-HT)(2A) receptor agonist 1-(2,5-dimet hoxy-4-iodophenyl)-2-aminopropane (DOI) on plasma glucagon levels were stud ied in rats. Systemic injection of DOI induces significant increases in pla sma glucagon levels. Hyperglucagonemia induced by DOI was dose-dependently prevented by the 5-HT2A receptor antagonist ketanserin. Adrenodemedullation abolished hyperglucagonemia elicited by DOI. Previous report demonstrated that the peripheral 5-HT2A receptor agonist induces hyperglycemia in rats b ut does not increase plasma glucagon levels at doses inducing hyperglycemia . Therefore, our findings suggest that DOI-induced glucagon release was eli cited by stimulation of the central 5-HT2A receptor, which in turn increasi ng adrenaline release.