GCG and type 2 diabetes mellitus: In the paper by Unger et al. (1970) similarly, statistically significant differences were not observed in fasting glucagon levels between CS and T2D subjects but when hyperglycemia was induced by glucose infusion in the CS so as to simulate the fasting hyperglycemia of T2D patients, mean glucagon fell significantly below the T2D mean, indicating the level of glucagonemia is high for the prevailing glycemia in T2D.