EXPERIMENTAL NERVOUS DIABETES 515 



It is very unlikely that the combustion of sugar in the pancreasless dog 

 ceases entirely. It must not be forgotten, that very intense grades of glyco- 

 suria occur not only in human beings, but that forms of diabetes may also 

 be produced in dogs, that are associated with a more intense elimination of 

 sugar than is the case'in pancreas diabetes. I refer to investigations of Lusk 

 on phloridzin diabetes, in which the quotient 3.6 was regularly attained. 

 Also in our investigations on simultaneous extirpation of the pancreas and 

 thyroid gland, and especially of pancreas and parathyroid glands were the 

 quotients high. Therefore in ordinary pancreatic diabetes it must either be 

 that less sugar is formed, or that sugar is still consumed. 



If we adopt the standpoint that the combustion of sugar in the muscles 

 is only possible after preceding assimilation, the experiments of Starling 

 would show that the glycogenesis in the muscles and probably also in other 

 cells that otherwise contain glycogen is, without the pancreatic hormone, 

 highly reduced. A certain grade of glycogenesis is always found remaining 

 in the pancreatic diabetic dog, as already mentioned. If we assume that in 

 the experiments of Forges and Salomon that only the carbohydrates just 

 assimilated is consumed to the last traces, we may readily bring it in harmony 

 with the assumption that the assimilation of carbohydrates in the muscles of 

 pancreasless dogs is diminished. It seems to me therefore that the two series 

 of experiments do not unconditionally contradict each other, if the fact is 

 emphasized that in the pancreasless dog the formation of glycogen is dis- 

 turbed not only in the muscles but also in the liver. 



It is very hard to explain the enormous increase of the protein decomposi- 

 tion, the salt- elimination, and especially also the caloric production, in the 

 dog with pancreatic diabetes. I shall return to this in the theoretical con- 

 siderations, later on. 



I might summarize what I have just detailed in the following hypo- 

 thesis: The pancreatic hormone is an exquisitely assimilatory hormone, 

 and governs glycogenesis in the liver and muscles. In the light grades of 

 insufficiency the disturbance in carbohydrate metabolism occurs only when 

 there are instituted great demands on glycogenesis in the liver (alimentary over- 

 loading with carbohydrates). In the severer disturbances there occurs, in addi- 

 tion to the disturbance in anabolism, a marked increase in catabolic processes 

 and thereby a faulty decomposition of higher and lower fatty acids (ketonuria) . 



B. Experimental Nervous Diabetes 



The experimental nervous diabetes will be mentioned here only briefly. 

 Many important facts have already been mentioned in the chapter on the 

 suprarenals. We have to thank Claude Bernard for the fundamental ex- 

 periment. A puncture at a definite place in the fourth ventricle leads in 

 many animals to a glycosuria lasting several hours. Recently Aschner has 



