Effect of Prolactin on Post-Castration Changes in Ultrastructure of the Ventral Prostates in Male Rats

Abstract

Two-month-old male rats were given daily intraperitoneal injections of 20IU PRL for 6 or 8 days and castrated on the 5th day of the treatment. At 30 hrs after castration the rough endoplasmic reticulum with cisternae arranged in parallel arrays was less numerous and isolated vesicles of the reticulum increased in epithelial cells of the ventral prostates in PRL-treated castrates as compared to vehicle-injected castrates. Morphometric studies revealed that lysosome-like dense bodies were smaller in size and less numerous in PRL-treated rats than in the vehicle-injected controls, although the effects of PRL were no longer detectable 78 hrs after operation. These findings suggest that PRL delays the early progress of involutionary changes in the ventral prostate epithelial cells by inhibiting the lysosomal system.