The influence of the sugar concentration of the blood on the protein metabolism in phlorhizin diabetes

Abstract

According to Rubner, the protein metabolism of a normal starving animal is composed of two fractions: The first fraction represents the protein metabolized in the life processes of the cells. The second fraction represents the protein burnt for the purpose of maintaining the temperature of the body. Landergren, however, presents considerable evidence to show that the “dynamogenetic quota” of Rubner is really the result of two distinct processes: I. The protein that is metabolized for the increased production of sugar, in cases where sugar is absent from the diet and the glycogen supply becomes low. It is a well-known fact, that in phlorhizin diabetes, the protein catabolism rises enormously; in some cases as high as five times the starvation requirements. Because of the renal origin of the glycosuria, there is a constant tendency for the concentration of the sugar in the blood to fall. The following experiment was performed in order to test what part, if any, the concentration of the sugar in the blood plays in the regulation of the protein metabolism. A dog was phlorhizinized in the usual manner, and the D: N ratio established. Seventy-five grams of glucose dissolved in water and divided into six doses were given per os on the fourth day of the glycosuria. 150 grams were given on the sixth day. From the D : N ratio on the third and fifth days, we may assume that the phlorhizin intoxication was complete and that the protein burnt on the fourth, sixth and seventh days yielded 3.6 gm. of glucose for every gram of nitrogen.