THE STIMULATION OF CANINE PROSTATIC SECRETION BY SYMPATHOMIMETIC AMINES

¹ Mason Research Institute, Worcester, Massachusetts

In unanesthetized, castrated, testosterone-treated dogs with surgically prepared fistulas which allowed the collection of prostatic fluid uncontaminated by urine, the intravenous administration of pilocarpine provoked a copious secretion of prostatic fluid while large doses of norepinephrine, isoproterenol, tyramine or ephedrine resulted in the secretion of only small amounts of fluid. Although they responded to electrical stimulation of the hypogastric nerves, only similarly small amounts of fluid were collected from anesthetized dogs in which the prostatic urethra was cannulated and norepinephrine and isoproterenol were administered as single injections or as continuous 30-min infusions. It is concluded that the capacity of the sympathomimetic amines to induce the formation of fluid by the secretory epithelium of the canine prostate gland must be quite limited and that the small amounts of fluid secreted in response to such drugs could have been expressed from the glands by contraction of their muscular elements.