542 METABOLISM, NUTRITION AND DIETETICS 



sympathetic nerve-endings may survive a considerable time. The 

 theory that epihephrin causes glycosuria by inhibiting the internal 

 secretion of the pancreas, and that the condition is therefore a par- 

 ticular variety of pancreatic diabetes, is erroneous. /Adrenalin 

 glycosuria does not seem to be in any way related to true 

 diabetes. / The complete metabolism of dextrose is not interfered 

 with. Indeed, a much larger proportion of the total heat produced 

 comes from the destruction of sugar after the subcutaneous injection 

 of epinephrin into dogs than in the normal animals (Lusk and Riche). 

 If in spite of this glycosuria ensues, it is only because the carbo- 

 hydrate reserve of the body is mobilized so rapidly that it cannot 

 possibly be all consumed. Nor does epinephrin cause any increased 

 production of sugar from protein or from fat. For in dogs rendered 

 diabetic by phlorhizjn and freed from glycogen by shivering, injec- 

 tion of epinephrin is not followed by an increase of either sugar or 

 nitrogen in the urine (Ringer). After repeated injections of adren- 

 alin, a tolerance for it is established, and glycosuria is no longer 

 caused. 



(Phlorhizin Glycosurial (produced by subcutaneous injection of the 

 gmcoside phlorhizin, agrees with pancreatic, but differs from punc- 

 ture diabetes in this, that it can be produced in an animal free 

 from glycogenj and is accompanied by extensive destruction of 

 proteins. It differs from other forms of diabetes in being associated, 

 not with an increase, but with a diminution, in the sugar of the blood. 

 This is best explained by supposing that the phlorhizin acts on the 

 kidney in such a way as to increase the permeability of the glomeru- 

 lar epithelium for sugar, or (in terms of the secretion theory of urine 

 formation) in such a way as to increase its sensitiveness to the 

 stimulus of sugar circulating in the blood. The sugar is therefore 

 rapidly swept out of the circulation, and this leads secondarily to 

 an increased production of sugar to make good the loss. In addi- 

 tion, within certain limits there is a total inability on the part of 

 the body to consume dextrose. 



After the preliminary sweeping out of the sugar already in the 

 body, a definite ratio is established between the dextrose and the 

 nitrogen eliminated in the urine (dextrose : nitrogen : : 3'6or 3-7 : i). 

 The sugar at this stage is produced entirely from proteins, and not 

 at all from fat. It is a fact of considerable interest that, if small 

 quantities of dextrose are now given, the amount of protein de- 

 stroyed is reduced to some extent, although all of the dextrose is 

 excreted, and none of it is burnt (Ringer). This supports the 

 hypothesis of Landergren that in starvation some of the protein is 

 metabolized for the formation of the indispensable dextrose, and 

 that this fraction can be ' spared ' by carbohydrate, though not by 

 fat. The protein metabolized is so much increased under the 

 influence of phlorhizin that it exceeds the starvation requirement 



