Effect of leuprolide on growth of rat prostatic tumor (R 3327) and weight of male accessory sex organs.

Leuprolide, a synthetic LHRH analog, inhibited growth of the Dunning R 3327 androgen-sensitive rat prostatic tumor and induced weight loss in male accessory sex organs. The relationship between the mode of administration and efficiency of the treatment was examined. Maintenance of the drug level in vivo seemed to be one of the important factors in the suppression of tumor growth, while a decrease in the weight of the accessory sex organs was mainly dependent on the dose administered. No treatment with leuprolide surpassed the effect caused by castration. Cytosolic androgen receptor and acid phosphatase activity in the tumor tissues were not changed significantly after treatment with leuprolide.