306 ADRENALS IN CARBOHYDRATE METABOLISM 



as a year, take on weight, show a normal amount of glyco- 

 gen, and differ from normal animals apparently only in the 

 fact that the glycosuric puncture has no effect on them. 20 

 It should be recalled, too, that hypoglycsemia and increased 

 tolerance for sugar has been met in sequence to removal of 

 the two adrenals in dogs and to Addison's disease in man. 21 

 Considerable importance on the other hand, should be 

 attributed to the finding that even in animals deprived of 

 the adrenals hyperglycaemia may be caused by irritation of 

 the central segment of the vagus nerve 22 ; this is a positive 

 indication that the ' l sugar centre ' ' can exert its power en- 

 tirely independently of the adrenals. It seems possible, 

 too, that the failure of puncture glycosuria and other re- 

 lated glycosurias 23 after extirpation of the adrenals, in the 

 course of which operation it is not unlikely that lesions of 

 the network of nerves about the kidney may have been pro- 

 duced (in line with what has already been said), may be ex- 

 plained with much probability and quite fully on the assump- 

 tion of some disturbance of the renal circulation. 



Chromium Affinity of the Adrenals. An observation of 

 Kahn is directly applicable to the second of our postulates. 

 "If one adrenal be removed from a rabbit and glycosuric 

 puncture be performed, and the second adrenal be extirpated 

 some time after the appearance of glycosuria, it will be found 

 on comparison of the two organs that the second one re- 

 moved has undergone very decided alteration. The affinity 

 for chromium is very greatly reduced, the cells are poor in 

 granules and rich in vacuoles ; the more minute vessels are 

 for the most part distended; and its adrenin is very much 



80 R. H. Kahn and E. Starkenstein (Prague), Pfliiger's Arch., 139, 181, 

 1911. 



21 0. Forges, 1. c. 



23 E. Starkenstein, 1. c. 



38 Cf. J. J. R. Macleod and R. G. Pearce, Amer. Jour, of Physiol., 29, 419, 

 1912. 



