348 



PHYSIOLOGY OF GONADS 



and Thieblot, 1951 ; Alcozer and Costa, 

 1954, Alcozer and Cliordano, 1954; Bailo, 

 1955). The reader is referred to a recent 

 book which summarizes the literature on 

 the pineal body (Kitay and Altschule, 1954 ) . 

 Extensive hepatic disease is associated 

 with testicular atrophy. Morrione (1944) 

 induced cirrhosis in male rats by means of 

 carbon tetrachloride. The testes of the 

 cirrhotic rats were not affected. However, 

 when estrogen was administered, severe 

 testicular atrophy occurred, much greater 

 than that induced by the same amount of 

 estrogen in control, noncirrhotic animals. 

 Testicular atroi^hy is said to occur in 70 per 

 cent of men who have cirrhosis of the liver 

 (Bennett, Baggenstoss and Butt, 1951). 

 There is no critical information from which 

 one could conclude that the atrophy of the 

 testis in cirrhotic men is caused by failure 

 of the diseased liver to inactivate estrogen. 



XV. Nonneoplastic Disorders 

 of the Testis 



Study of certain hypogonadal disorders 

 of man has provided information of general 

 interest and bearing on the physiology of 

 the mammalian testis. For an index to the 

 large clinical literature on pituitary-testis 

 relationships, the reader may consult Heller 

 and Nelson (1948) and Albert, Underdahl, 

 Greene and Lorenz (1953-1955). A group of 

 spontaneously occurring disorders shows 

 clearly the control of the testis by gonado- 

 trophin. In pituitary dwarfism, the testis 

 remains infantile even as late as 30 or 40 

 years of age, and perhaps for the entire life 

 span of tlie individual so afflicted. Leydig 

 cells are not jirescnt, and the tubules con- 

 tain only undifferentiated cells and occa- 

 sional spermatogonia. Pituitary dwarfism is 

 a form of hypopituitarism in which all hor- 

 mones of the anterior lobe may be absent. 

 Anotiiei' type of hyi)ogonadism in man is 

 restricted to the loss of only the gonado- 

 trophic function of the pituitary. In this 

 syndrome, the testis does not contain ma- 

 ture Leydig cells or mature tul)ules. This 

 syndrome represents a condition that can- 

 not be duplicated in lower animals. A few 

 instances of a selective type of gonado- 

 tropliir insuflficiency have been described in 

 which tubular maturation proceeds, with 

 (liffei'entiation of the Sei'toli cells and the 



formation of sperm. However, Leydig cells 

 are not present. This syndrome ("fertile 

 eunuchs"), if interpreted in terms of the 

 dualistic concept of pituitary control of the 

 testis, is explainable on the basis that for- 

 mation and secretion of FSH have occurred 

 but that LH is absent. If pituitary lesions 

 occur before puberty, the testes remain im- 

 mature. Pituitary lesions occurring after 

 maturity cause atrophy of the seminiferous 

 epithelium, not immaturity. The adult tu- 

 bule of man cannot dedifferentiate as does 

 the mature Leydig cell following hypo- 

 l^hysial deprivation. The atrophy may vary 

 in severity from hypospermatogenesis to 

 complete sclerosis. Lack of gonadotrophin in 

 the adult also results in thickening of the 

 tubular wall and atroph}^ of the Leydig cells. 



The most common defect in the human 

 testis is failure of the seminiferous tubules. 

 In contrast to the pituitary deficiencies, 

 which generally result in both tubular and 

 androgenic failure, disorders of sj^ermato- 

 genesis lead only to infertility. The Leydig 

 cells are normal, and androgenic function is 

 unimpaired. The disordered spermatogenesis 

 and the presence of cellular debris in the 

 lumen are reflected by an abnormal spermo- 

 gram. Depression of the sperm count to the 

 point of azoos]M'rmia, abnormal sperm cells, 

 and poor motility are characteristic find- 

 ings. Another type of primary testicular dis- 

 order associated with azoospermia is germi- 

 nal aplasia, in which the tubules contain 

 only Sertoli cells. The Leydig cells are nor- 

 mal; hence, androgenic function is normal. 

 Klinefelter's syndrome also is associated 

 with azoospermia but the function of the 

 Leydig cells is variable, ranging from se- 

 vere insufficiency, in which the afflicted per- 

 sons are eunuchoidal, to mild insufficiency, 

 in which the liabitus is normal or almost so. 



Testicular disorders are not restricted to 

 man. They occur in common laboratory ani- 

 mals and in veterinary practice. Their simi- 

 larity to some of the clinical entities just 

 described will be evident. 



A genito-urinary abnormality occurs in 

 20 per cent of males of the A x C rat (Vilar 

 and H(n-tz, 1958). On one side, the testis is 

 atroi)hic and the kidney, ureter, ductus 

 deferens, epididymis, and seminal vesicle 

 are absent; however, the coagulating gland 

 is |)r('scnt. The testis is noi'mal ])i'epul)ertally 



