INTERNAL SECRETION OF TESTICLE 153 



5. The Influence of X-rays on the Testicle. 



Since X-rays have been used in medicine it is known that 

 steriUty can be caused by them without any visible changes in 

 the somatic and psychical sexual characters. A number of 

 authors have experimented on this question with animals also 

 and there is general agreement among them that X-rays can 

 cause sterility without interfering with sexual activity (Albers- 

 Schonberg, 1903). Later it was shown by Bergonie and 

 Trihondeaii (1904, 1905) that X-rays cause a degeneration of 

 the seminiferous tubules, whereas the interstitial cells and the 

 cells of Sertoli are not altered. Even a single irradiation could 

 produce this effect provided the irradiation was strong and 

 long enough. The authors also called attention to the fact 

 that simultaneously with the atrophy of the tubules there is a 

 proliferation of the interstitial cells, their number being 

 sometimes two or three times greater than normally. Also a 

 proliferation of the ceUs of Sertoli was reported. Villemin 

 (1906 a) confirmed the statements of Bergonie and Tribondeau, 

 An investigation upon this question was made also by Tandler 

 (1913) on the roedeer. Several months after irradiation the 

 seminiferous tubules were in a state of degeneration, whereas 

 the interstitial cells were normal. The roedeer treated 

 with X-rays cast and regrew their antlers like normal 

 animals. 



Objections may be made to the assumption that in these 

 experiments a complete suppression of the activity of the 

 seminiferous tubules had taken place. Bergonie and Tri- 

 bondeau (1904) and Villemin (1906 b) found that a regeneration 

 of the degenerated tubules can occur if the irradiation was not 

 too strong. Villemin showed that this result takes place only 

 when besides the cells of Sertoli the spermatogonia also are 

 resistant to X-rays. The question of regeneration was studied 

 further by Simmonds (1909), who records that some tubules 

 may persist unaltered even after radiation of long duration; 

 in regenerated tubules he found spermatozoa. Simultaneously 

 with the regeneration of the tubules the interstitial tissue 

 decreases. This latter observation might be taken as further 

 evidence that the increase of interstitial tissue after degenera- 

 tion of tubules is often only apparent, the extension of this 

 tissue being only greater in comparison with the diminished 



