MAMMALIAN TESTIS 



323 



have transient testicular atrophy. Hormonal 

 secretion is not impaired (Huggins, Masina, 

 Eichelberger and Wharton, 1939). Testicu- 

 lar atrophy has been noted in schizoid pa- 

 tients (Hemphill, 1944; Hemphill, Reiss 

 and Taylor, 1944) and was thought to be 

 caused by this severe mental illness. How- 

 ever, the histopathologic appearance of the 

 testis in schizophrenia is not specific (Blair, 

 Sniffen, Cranswick, Jaffe and Kline, 1952; 

 Tourney, Nelson and Gottlieb, 1953) and it 

 may not be stated that mental illness has 

 any direct or specific action on the human 

 testis. 



VIII. The Excretory Duct System 



The old concept that vasectomy is fol- 

 lowed by hypersecretion of male hormone 

 and rejuvenation has been disproved com- 

 pletely. Recent studies have been concerned 

 with the effects of occlusion of the excretory 

 ducts on the tubular apparatus. Although 

 some reports have indicated that the testes 

 of rats and rabbits decrease to one-half 

 normal size after vasoligation, the majority 

 opinion is that no change in testicular 

 weight occurs (see Young, 1933, for re- 

 view). Poynter (1939) did not observe any 

 changes in the structure of the rat testis 

 one year after vasoligation. Atrophy of the 

 testes w^as obtained only when vasectomy 

 was performed scrotally; under these cir- 

 cumstances, it resulted from adhesions sub- 

 sequent to operation. No change was ob- 

 served in the seminal vesicles, indicating no 

 alteration in secretion of androgen. Also, 

 no changes were evident in the Leydig cells. 



Ligation of the ductuli efi'erentes, how- 

 ever, does produce pressure atrophy of the 

 germinal epithelium (Young, 1933; Mason 

 and Shaver, 1952). The testis becomes 

 swollen and tense owing to distention of the 

 ductuli with sperm on the testicular side of 

 the ligature. The rete is also dilated. Peri- 

 tubular fibrosis occurs, especially in tubules 

 at the periphery of the testis. Degeneration 

 of the germinal epithelium then ensues. 

 Ten weeks after ligation, only Sertoli cells 

 are left in the tubules. The Leydig cells re- 

 main unscathed (Harrison, 1953a). 



The dift'erence in effect of ligation of the 

 excretory path distal or proximal to the 

 epididymis is attributable to the function of 

 the excretory duct system of reabsorbing 



fluid needed to carry sperm. Obstructive 

 necrosis of the testis does not occur after 

 ligation of the ductus deferens, because 

 reabsorption of fluid takes place. This 

 would also explain the absence of testicular 

 atrophy in clinical states of inflammatory 

 obstruction along the excretory pathway 

 caused by gonorrhea or of obstruction 

 caused by congenital absence of the duc- 

 tus deferens. 



IX. The Seminiferous Epithelium 



Clarification of the spermatogenic cycle 

 in the germinal epithelium is probably the 

 most important development in knowledge 

 of the testis since the second edition of this 

 book. The difficulties in expressing sper- 

 matogenesis in quantitative terms were 

 great. Clear identification of each type of 

 cell was not possible. Certain basic informa- 

 tion on the transformation of one type of 

 cell into another, on the renewal of certain 

 cells, and on degenerative phenomena was 

 lacking. Despite these difficulties, the time 

 of a complete spermatogenic cycle in the 

 rat was estimated by several investigators 

 using diff"erent methods. These methods 

 were ( 1 ) time of recovery after irradiation 

 of the testis, (2) morphologic studies of the 

 changes in cellular population with ref- 

 erence to a static cell such as the Sertoli cell, 

 and (3) turnover time of organically bound 

 radiophosphorus in the germinal epithelium 

 (Howard and Pelc, 1950). The introduction 

 of the periodic acid and fuchsin sulfurous 

 acid (PAS) stain for glycol groups such as 

 exist in glycogen, mucoprotein, and muco- 

 polysaccharides solved the difficulties enu- 

 merated above. 



Cytologic studies have shown that the 

 cells of the seminiferous epithelium are or- 

 ganized in similar associations. The de- 

 velopment of any one generation of a cer- 

 tain type of cell is correlated with other 

 generations present in the same part of the 

 tubule. The changes in a certain zone of the 

 germinal epithelium between two successive 

 appearances of the same cellular association 

 constitute a cycle. Different investigators do 

 not use the same number of phases, the same 

 classification of cell types, or the same 

 points of reference. Depending somewhat on 

 the cytologic detail and somewhat on the 



