176 FRANCIS M. POTTENGER 



center nea$ the tuber cinereum. Factors which cause marked stimulation 

 of the sym pathetics, such as the major emotions, as shown by Cannon, are 

 followed by glycosuria. 



Hormone Factors in Glycogenolysis. Not only is glycogenolysis fa- 

 vored by stimulation of the sympathetic nervous system, but also by hor- 

 mones produced by certain glands of internal secretion, particularly the 

 suprarenals, thyroid, and pituitary. It will be noted that these glands are 

 particularly identified with the sympathetic nervous system. Hyperf unc- 

 tion on their part may be accompanied by glycosuria. This is especially 

 well recognized in case of the suprarenals and thyroid. An observation 

 which was first made by Ludwig and Kraus, that certain cases of hyper- 

 thyroidism show glycosuria, has been explained by Eppinger as being in 

 patients of the sympathicotonic type ; on the other hand, glycosuria should 

 not be expected to occur in the vagotonic. Hypofunction on the part of 

 the thyroid is likewise followed by hypoglycemia. Janney (a) says: "The 

 clinical occurrence of the low blood sugar values in diseases presenting 

 hypofunctional condition of ductless glands (cretinism, myxedema, Addi- 

 son's disease, hypopituitarism) unmistakably indicates the general signifi- 

 cance of these symptoms." 



Macleod and Pearce have shown that splanchnic stimulation fails to 

 produce hyperglycemia in animals from which the adrenals have been 

 previously removed. At the same time Macleod does not believe that gly- 

 cogenic disturbances can be wholly divorced from the sympathetic nerves 

 and attributed wholly to epinephrin action, and cites the fact that stimu- 

 lation of the previously cut nerves of the hepatic plexus in a normal 

 animal, without any stimulation of the adrenals having occurred, pro- 

 duces hyperglycogenolysis. 



V. Fur tli and Schwartz reviewed the experiments and suggestions of 

 Ziilzer and von Noorden as to the antagonistic action of the chromaffin 

 tissue and the pancreatic hormone, and came to the conclusion that such 

 an antagonism exists. 



Sometimes disease of the hypophysis is accompanied by glycosuria. 

 An explanation of this, aside from a hormone action, has been offered by 

 Aschner (a) (?;), who suggests that the glycosuria is produced by stimu- 

 lating the sympathetic nervous center, which Karplus and Kreidl have 

 shown to exist near the tuber cinereum. 



From this discussion it may be assumed that the cause of fflvcosuria is 



1 O </ 



hound more or less complexly with the hormone produced in the pancreas, 

 on the one hand, and the sympathetic nerves and the endocrin glands re- 

 lated to it, particularly the suprarenals, pituitary, and thyroid, on the 

 other hand. AYhethor the absence of the pancreatic hormone, when the 

 islands of Langerhans are destroyed, allowing the sympathetic system and 

 the sympathicotropic hormones to functionate unopposed, is a small or 

 large factor in the cause of diabetes, is not fully determined. Neither do 



