Some Endocrine and Related Factors Influencing Spermatogenesis
In the last two or three decades, important papers have appeared concerning the effects on spermatogenesis of diet including vitamins, of bacterial toxins, of alcohol, of tuberculin, of vasectomy, of testicular transplantations, of radiation of light, of seasonal rhythms, of sexual excess, of venereal disease, and of age, but a complete review of the literature is impossible here. The purpose of this report is to summarize some of the results of recent studies on experimentally induced testicular atrophy and repair and to indicate the possible value of such findings clinically.
That gonadal activity is dependent on the anterior lobe of the pituitary gland has been known since Crowe, Cushing and Homans1 performed their notable experiments on dogs. They demonstrated that removal of the posterior lobe of the pituitary gland did not influence the genital development of dogs but that complete removal of the gland resulted in an atrophic condition of these organs. Some investigators have claimed that the genital atrophy following hypophysectomy is due to brain injury. Although brain injury may influence the genitalia, there now remains no question but that prehypophyseal hormones are necessary for normal gonadal activity.
A great portion of our knowledge concerning the effects of hypophysectomy has been the result of observations on the rat, commencing with the classical work of Smith2. If male rats are hypophysectomized before puberty, they never become sexually mature. The accessory sex glands remain infantile in appearance and the testes decrease in size. Spermatogonia and Sertoli cells remain normal in. . .