420 



Scientific Proceedings (131) 



8. Thus far no definite evidence has been obtained to show 

 that the carbohydrate tolerance of a diabetic patient is perma- 

 nently raised by temporary extract treament. 



205 (2165) 



The degeneration of the testis of rats on a milk diet. 



By H. A. MATTILL and J. S. CARMAN. 



[From the Physiological Laboratory of the University of 

 Rochester, Rochester, N. Y.] 



The degeneration of the testis of rats on rations in which all 

 the protein and vitamines are supplied by milk 1 has also been 

 observed when such rations are supplemented by nucleoprotein 

 and by those proteins of first quality 2 found in kidney and liver. 

 When 2 per cent, or 5 per cent, of these dried tissues- or 2 per 

 cent dried thymus (Parke, Davis) or 2 per cent, yeast nucleic 

 acid was supplied in rations containing 50 per cent, dry whole 

 milk, 15 per cent., lard, 2 per cent., salts, and starch, evidences of 

 degeneration and atrophy appeared as early as 155 days of age. 

 Among 27 animals on such rations, the oldest animal still pos- 

 sessing normal gonads was 139 days of age. Of 25 animals 

 over 155 days of age only one had gonads whose weight was 

 normal and in this animals there were other evidences of degen- 

 eration. Without exception litter mates of these animals on 

 stock rat food had normal organs. Aside from the decreased 

 weight which was occasionally even less than one-half the normal 

 for the weight of the animal the degenerating glands have a 

 semitransparent glassy appearance; when ruptured they collapse 

 and there exudes a clear colorless liquid which coagulates like 

 lymph. Histologically these glands show a profound degenera- 

 tion of the germinal epithelium and an abundant proliferation 

 of the interstitial tissue together with numerous clear amorphous 

 areas. In the main these are the features which Allen 3 de- 

 scribed as resulting from the absence of water-soluble B in the 

 diet. Since in our milk rations there can be little or no question 

 as to the adequacy of the vitamin B supply, especially when liver 

 or kidney is added, it would appear that the lack of some other 

 substance than vitamin B, and as yet unrecognized, may be 

 solely or jointly concerned in the disappearance of the repro- 

 ductive function. 



1 Mattill, H. A., and Stone, N. C, Jour. Biol. Chem., 1923, Iv, 443. 



2 MeCollum, E. V., Simmonds, N., and Parsons, H. T., J. Biol. Chem., 

 1921, xlvii, 235. 



3 Allen, E., Anat. Etc., 1919, xvi, 93. 



