Measurement of blood flow to the ventral prostate in the rat with radioactive microspheres: effects of estradiol-17 beta and human chorionic gonadotrophin.

The function and size of the rat ventral prostate are stimulated by androgens and inhibited by estrogens. In order to test whether the blood flow in prostate is influenced in a similar fashion prostatic blood flow was measured after administration of human chorionic gonadotrophin (hCG) in rats with and without pretreatment of estradiol-17 beta (E2) and in rats castrated for five days with and without treatment with E2. Prostatic blood flow was measured with the microsphere technique, which allows blood flow measurement without any interference with the organ. E2 treatment resulted in a decreased prostatic blood flow in both intact and castrated rats, and blood flow was restored to normal in intact rats after hCG-injection. It was concluded that the E2 induced decrement of prostatic blood flow was at least in part mediated by a direct effect on the prostate.