Venous Arterial Interactions Involving Serotonin in the Pampiniform Plexus of the Rat

Abstract

Serotonin injected into the spermatic vein had a marked depressor effect on the testis artery at dose levels having no observable effects on central blood pressure. This venous arterial interaction was not dependent on capillary flow between the vein and artery, on flow through the vasal or epididymal artery, on venous pressure or on changes in the vas deferens. Transfer of tritiated water from the spermatic vein to testis artery was demonstrated, indicating that such molecular transfers were possible. It was concluded that serotonin in the spermatic vein can bring about a marked constriction of the testis artery without entering the general circulation, probably by passing directly from the vein to the artery in the pampiniform plexus.