INTERACTION OF INTERNAL SECRETORY GLANDS 315 



tuber cinereum) that the glycosuria of hypophyseal affec- 

 tions may be explained as depending upon an irritation of 

 the base of the brain. This is the more likely because of the 

 existence here of both vagus and sympathetic paths, and an 

 irritation of the sympathetic is apparently directly capable 

 of giving rise to glycosuria." 



In this connection it seems to be of great interest that it 

 has been found possible in E. Gottlieb's laboratory to pro- 

 duce a sensitization of sympathetic nerve endings by consti- 

 tuents of the hypophysis in the same way that this had been 

 previously accomplished by components of the thyroid (Vol. 

 I of this series, p. 457, Chemistry of the Tissues). Proof of 

 sensitization of the points of attack of suprarenin was ob- 

 tained both by the Lawen-Trendelenburg frog preparations 

 and by mydriasis of the enucleated frog's eye. Emphasis 

 has been properly laid upon the point that as long as we 

 know nothing of an internal secretion of the constituents of 

 the hypophysis we are really not in position to insist upon 

 the physiological significance of this phenomenon. We can- 

 not help, however, considering such sensitizing of the points 

 of attack of one internal secretion by another internal secre- 

 tion in trying to explain the physiological balance of the 

 system and its disturbances. 45 



A rather impressive complement to the above-mentioned 

 discoveries may be recognized in the observations of 

 B. Aschner 46 according to which in young dogs the glyco- 

 suria caused by adrenin may be markedly suppressed by 

 extirpation of the hypophysis, possible not only in the first 

 few days after the operation but for months. It is espe- 

 cially noteworthy that the skin necroses, which so often 

 occur in case of adrenin injections, are not met in such in- 

 stances at all or only rarely. This, it might be suggested, 

 may be due to the fact that the vaso-constricting influence 

 of the adrenin has been weakened. 



Kepinow (R. Gottlieb's Lab., Heidelberg), Arch. f. exper. Pathol., 67, 

 247, 1912. 



*" Aschner, 1. c., pp. 105-106. 



