EFFECT OF FOLLICLE-STIMULATING HORMONE AND INTERSTITIAL CELL-STIMULATING HORMONE ON SPERMATOGENESIS IN LONG-EVANS RATS HYPOPHYSECTOMIZED FOR SIX MONTHS

Abstract

ABSTRACT The effects of sheep interstitial cell-stimulating hormone (ICSH) and follicle-stimulating hormone (FSH) on spermatogenesis were studied in rats of the Long-Evans strain six months after removal of the pituitary gland. The results confirm the contention that sheep ICSH alone is not an effective agent for stimulating repair of the epithelium of the seminiferous tubules of the rat, and that preparations of sheep FSH contain a principle which, in the presence of less than 1 μg of ICSH per day, can stimulate substantial repair. All the effects obtained with gonadotrophin preparations can be accomodated if one assumes that FSH is specifically concerned with some critical step in the evolution of the primary spermatocyte and that androgen is responsible for maintaining a favorable intratubular environment in which the germ cells can develop. A complication encountered in this study was an unexpected variation in the germ cell population of rats that had been hypophysectomized for a period of 6 months; the possibility that residual gonadotrophin may account for this observation is discussed.