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Updated: Aug 11, 2026

A Method of Nodose Ganglia Injection in Sprague-Dawley Rat
Published on: November 25, 2014
Gramine: a vasorelaxing alkaloid acting on 5-HT(2A) receptors
Guglielmina Froldi1, Barbara Silvestrin, Paola Dorigo
1Department of Pharmacology and Anaesthesiology, University of Padova, Padova, Italy. g.froldi@unipd.it
Abstract:
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.
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