Abstract

Bulbocapnine was found to have an adrenergic blocking effect on cat and dog blood pressure. This antagonistic effect was also seen on the isolated rabbit ear and isolated rabbit jejunum but not on the carbachol stimulated rat uterus. Bulbocapnine had no effect on responses to iso-proterenol but potentiated the responses to vasopressin on dog and not on cat blood pressure. It is concluded that bulbocapnine is an α-adrenergic blocking agent and has no effect on β-adrenergic receptors.

A serotonin antagonism by bulbocapnine was denmonstrated on cat and dog blood pressure, isolated rabbit ear, isolated rabbit jejunum, and isolated rat uterus. The possible role of these antagonistic effects in the mechanism of experimental catatonia is briefly discussed.