EXPERIMENTAL DIABETES 



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In from one to two hours after the puncture, or even sooner, 

 sugar appears in the urine. In the rabbit, the glycosuria 

 disappears after five or six hours, seldom lasting twenty-four. 

 In the dog, on the other hand, it may last as long as seven 

 days. If the animal be killed and the liver examined after the 

 sugar has disappeared from the urine no glycogen, or only a 

 trace of it, will be found. On the other hand, if the animal be 

 starved for several days previous to the puncture and the 

 store of glycogen be thereby greatly reduced no glycosuria will 

 follow the puncture. 



To illustrate these statements, the following table of results, 

 obtained by Dolley and the author, may be of interest. 



TABLE II 



The percentage of sugar in the blood during the presence of the 

 glycosuria is considerably above the normal. All these facts point 

 to the glycosuria being due to the too rapid transformation of 

 glycogen into sugar. If we accept Bernard's theory, we can state 

 that hyperglycogenesis has occurred ; if Pavy's, we must assume 

 that, instead of being transformed into fat and proteid, the 

 glycogen has become hydrolysed into dextrose : in both cases 

 hyperglycsemia would be caused. 



It is interesting to note here that tumours in various parts of 

 the central nervous system in man have frequently been found, 

 post-mortem, where glycosuria had been one of the symptoms 

 before death. 



The puncture of the medulla acts by producing irritation of the 

 diabetic centre, and not, as might be imagined, by its destruction. 

 The short duration of the glycosuria, as well as the fact that if 

 the animal be kept under anaesthesia no glycosuria occurs on 



