SENSITIVITY OF THE REPRODUCTIVE SYSTEM OF HYPOPHYSECTOMIZED 40 DAY MALE RATS TO GONADOTROPIC SUBSTANCES1

Abstract

The testis wts. of rats hypophysectomized at 40 days of age were maintained for 15 days by gonadotrophic agents (pregnant mare serum, human chorionic gonado-trophin and pituitary interstitial cell stimulating hormone) given in doses less than the unit defined in the [female] rat (RU). Differentiation leading to the formation of spermatozoa within 15 days (that is, by 55 days of age, which is approx. normal for the rat of this colony) occurred with all 3 hormones at daily doses approx. 1/4 of a R.U. The interstitial tissue regressed when under the influence of those doses of gonadotrophins which were adequate to influence the size and activity of the testicular tubules. At least one unit was necessary to maintain the interstitial cells. The [male] accessory organs (seminal vesicles and prostate), also required higher doses for maintenance and growth than did the testicular tubules.