Protein sparing by glucose in experimental diabetes

Abstract

In diabetes there are abnormalities not only in carbohydrate but also in protein and fat metabolism as well. There is frequently a marked loss of protein in this disease, which may be either direct or the result of a failure on the part of carbohydrate to spare protein. Our experiments deal with one phase of protein metabolism in experimental diabetes, the influence of the removal of the major portion of the pancreas on the characteristic protein sparing action of glucose. For this purpose several female dogs weighing between nine and fifteen kilograms each were selected. Both the fasting nitrogen elimination and the effect of glucose feeding on this excretion were determined. During the fasting period the animals received only 40 c.c. of water per kilo. On the sugar days they received in addition 15 gm. of glucose per kilo. An after-period during which the glucose feeding was withdrawn was then introduced. Dr. Allen, of the Rockefeller Institute, then removed surgically about 90 per cent. of the pancreas. The wounds healed aseptically and the animals were allowed from two to five weeks to recuperate. The procedure consisting of fore-glucose and after-periods just described was repeated. In spite of the large loss of pancreatic tissue the protein-sparing action of glucose was not diminished in any of the animals. It appears that pancreatic tissue is provided far in excess of actual requirements or that this gland is not solely responsible for the protein-sparing action of carbohydrates. Dr. Ringer found this function intact in dogs made completely diabetic by means of phlorizin.