Further evidence for adrenergic transmission in the human vas deferens.

Abstract

Isolated portions of human vas deferens responded to field stimulation of the intramural nerve fibers or to exogenously applied noradrenaline [norepinephrine] with rhythmical contractions of both longitudinal and circular muscle layers. In guinea pig and rabbit vas deferens, field stimulation produced an initial rapid twitch response which was not found with human vasa. Responses of the human vas to field stimulation were depressed by the .alpha.-adrenoceptor blocking agents phentolamine and yohimbine. Motor innervation of the human vas deferens is apparently adrenergic and the relevance of this to the physiologic operation of the tissue is discussed.