Partial inhibition of castration induced ventral prostate regression with actinomycin D and cycloheximide.

Sprague Dawley male rats were injected subcutaneously with either actinomycin D or cycloheximide in saline immediately after castration. Control animals received saline only. Treatment was repeated daily for 4 subsequent days, and 24 hr after the last injection rats were sacrificed by decapitation. Ventral prostates were dissected and weighed. Actinomycin D and cycloheximide administration significantly reduced the rate of prostatic weight loss in castrated rats; serum testosterone levels in the control and drug treated animals were comparable. Histologic studies of the prostates indicated that drug treated animals had more active epithelial cells than saline injected controls. These results indicate that the rate of prostatic regression induced by castration can be modified by drugs such as actinomycin D and cycloheximide.