Responses of Rat Testes and Accessory Glands to Testosterone, Pilocarpine and Copulation

Abstract

ATROPHY of the interstitial cells and a decrease in testis size occur in the rat after treatment with testosterone propionate¹, the response being attributed to the inhibitory action of the androgen on gonadotrophin secretion. The ability of testes to respond to gonadotrophic hormones is dependent in some way, however, on the sympathetic nervous system^2,3. Increased concentrations of androgens in spermatic vein blood⁴ and peripheral plasma⁵ immediately after copulation imply a neuroendocrine process for Leydig cell secretion. Some of the accessory glands, which are target organs of androgens, atrophy in non-copulating male rats^6,7, but they may be stimulated with pilocarpine nitrate, a drug that produces cholinergic and concomitant triggering of certain adrenergic secretions⁸. This experiment was designed to study both the effects and possible relationships of alterations in male reproductive glands produced by testosterone propionate, pilocarpine nitrate and copulation.