Pharmacological Studies with Rescinnamine, a New Alkaloid Isolated from Rauwolfia serpentina

Abstract
Rescinnamine produced the typical pharmacological effects of R. serpentina: bradycardia, hypotension, sedation and characteristic alterations in cardiovascular responses. It caused augmentation of the pressor response to epinephrine, reversal of the pressor response to hypoxia, diminution of the pressor response to bilateral carotid occlusion, and blockade or reversal of the primary blood pressure rise elicited by faradization of the afferent vagus. The sedative effects of rescinnamine were demonstrated by gross observation in dogs, rats and mice, and by prolongation of pentobarbital induced sleeping time in mice. Rescinnamine produced marked eyelid ptosis in mice and a copious nasal discharge in rats. On a wt. basis, it appeared to be several times as potent as Rauwiloid and similar to reserpine. Rescinnamine is the second highly potent alkaloid derived from R. serpentina.