Gramine: a vasorelaxing alkaloid acting on 5-HT(2A) receptors.
The vascular effects of gramine on resistance vessels were evaluated, in particular as regards the 5-hydroxytryptamine (5-HT) system. We compared the action of gramine with that of ketanserin, a 5-HT (2A) antagonist; both compounds induced concentration-dependent relaxation in precontracted arterial rings. Also, the 5-HT concentration-effect curve shifted to the right in the presence of gramine, like ketanserin. These results suggest that gramine is a vasorelaxing agent acting mainly by antagonism at 5-HT (2A) receptors.
Froldi
Guglielmina
G
Department of Pharmacology and Anaesthesiology, University of Padova, Padova, Italy. g.froldi@unipd.it
Silvestrin
Barbara
B
Dorigo
Paola
P
Caparrotta
Laura
L
D000470:Alkaloids / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D001158:Arteries / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D026121:Indole Alkaloids; D007650:Ketanserin / Q000494:pharmacology; D009126:Muscle Relaxation / Q000187:drug effects*; D008517:Phytotherapy; D006109:Poaceae; D051381:Rats; D017208:Rats, Wistar; D012702:Serotonin Antagonists / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use
D000470:Alkaloids; D026121:Indole Alkaloids; D012702:Serotonin Antagonists; D014665:Vasodilator Agents; D007650:Ketanserin; C007884:gramine