THE EFFECT OF GLUCAGON PREPARATIONS ON THE UPTAKE OF GLUCOSE BY ISOLATED RAT DIAPHRAGM

Abstract

SUMMARY: The uptake of glucose by isolated rat diaphragm is increased in the presence of glucagon preparations (at concentrations of 20–200 μg/ml.). Evidence is produced which appears to show that this effect is due to the presence of insulin in preparations of glucagon. The insulin content of an amorphous preparation of glucagon, assayed with isolated diaphragm, appeared to be of the order of 1% (w/w). In view of this finding, it is suggested that no conclusions can be drawn about a possible effect of glucagon on carbohydrate metabolism in muscle until preparations are available which are entirely free from insulin.