410 THE LIVER. 



formed, as well as the origin of the sugar, but according to the views of 

 HAMMARSTEN such conclusions are mostly very uncertain. The sugar 

 eliminated by the urine represents the difference between the total sugar 

 production of the body and the quantity of sugar burned or utilized. 

 Only under the supposition that the body cannot burn or utilize any 

 sugar, is the sugar of the urine a measure of the quantit}' produced, 

 and this seems to be the case in phlorhizin diabetes ; but it is 

 difficult to decide how these suppositions apply to the different forms 

 of diabetes. Still several observations seem to show that in the different 

 forms of diabetes variable amounts of the sugar are burned, and only 

 in special cases can we draw approximately accurate conclusions. 



The property of protein of increasing the elimination of sugar is 

 considered as an important proof of the formation of sugar from protein. 

 In this regard those experiments are of special interest in which the 

 diabetic animal is allowed to starve until the urine is poor in sugar or 

 indeed free from sugar, and then on feeding with protein, an abundant 

 elimination of sugar is produced. If we do not accept the view in this 

 case that the protein, but rather the fat, was the material from which 

 the sugar was produced, still we must admit either of a sugar-sparing 

 action due to protein or of a strong sugar formation from fat, incited 

 by the protein. 



A sparing in the sense that the protein is oxidized instead of the sugar, 

 and in this manner protects it, is naturally possible only under the sup- 

 position that the body can burn at least a part of the sugar, otherwise 

 there would be nothing to spare and nothing to protect from burning. 

 The assumption of such an indirect action of proteins is difficult to recon- 

 cile with the common view of the inability of the body to burn sugar 

 in diabetes. LUTHJE l has communicated one experiment among others, 

 in which a dog with pancreas diabetes, \\hose weight before starvation 

 was 18 kilos, with nineteen days' starvation eliminated an average of 

 10.4 grams sugar for the last six days of starvation. By exclusive pro- 

 tein feeding the quantity of sugar per day could be raised to a maximum 

 of 123.0 grams, and as average it was 97.5 grams for the ten protein 

 days. The protein, therefore, had protected daily an average of 87 

 grams sugar from burning, which is hardly possible; and if in the diabetic 

 animal we admit of this considerable power of burning sugar, the quotient 

 D:N becomes valueless as a measure of the quantity of sugar formed. 



If, on the contrary, we admit of an indirect action of proteins in 

 that they incite a sugar formation from fat, perhaps by a certain very 

 important increase in the activity of the liver, we are opposed by the 

 great difficulty that, according to known laws of metabolism, the pro- 



1 Deutsch. Arch. f. klin. Med., 79. 



