Effects of Finasteride and Castration on Rat Ventral Prostate

Oh, Bong Ryoul; Ahn, Kyu Youn; Kwon, Dong Deuk; Lim, Joung Hwan; Park, Kwang Sung; Ryu, Soo Bang; Park, Yang Il

Abstract

PURPOSE
To compare the mechanism of cell loss and changes in the ventral prostate of young adult Sprague-Dawley rats after treatment with finasteride, a potent 5 alpha-reductase inhibitor, or castration.
MATERIALS AND METHODS
Rats were divided into two group: finasteride treated and castrated. Finasteride-treated rats were given 1 mg/kg a day orally. The rats were sacrificed on days 1, 3, 5, 7, 10, 14, and 21. The ventral prostate was weighed and either prepared for histologic examination to detect apoptotic evidence or frozen in liquid nitrogen for the determination of the intraprostatic dihydrotestosterone (DHT) concentration and DNA content.
RESULTS
Both finasteride and castration decreased prostate weight and DNA content, the decrease being more pronounced in the castrated group. By 3 days of finasteride treatment, the intraprostatic DHT concentration decreased to a greater extent with no further significant change thereafter, whereas castration gradually decreased the intraprostatic DHT concentration up to day 10, with no further significant decrease thereafter. Apoptotic bodies were typically observed in castrated but not finasteride-treated animals.
CONCLUSIONS
Castration caused a more profound involution of rat ventral prostate than did finasteride. The extent of prostatic involution did not correlate with the intraprostatic DHT concentration. We could not find evidence of apoptosis in finasteride-treated animals.