Comparative study of the vasodilatory effects of three quinazoline alkaloids isolated from Evodia rutaecarpa

The vasoreactivity of dehydroevodiamine (1), evodiamine (2), and rutaecarpine (3), quinazoline alkaloids isolated from Evodia rutaecarpa, to aorta smooth muscle demonstrated that they produce a vasodilatory effect on endothelium-intact rat aorta with equal potency. Compound 3 produced a full (100%) nitric oxide-dependent vasodilatation, whereas 2 and 1 produced a partially endothelium-dependent effect, 50% and 10%, respectively. At the same time, I and 2 may also act by other mechanisms, including probably an alpha1-adrenoceptor blocking action and a 5-HT antagonizing action, respectively.