Our observations show that in STZ-induced type 1-like diabetes, the amylase-stimulated increase in glucagon release does not affect the hyperglycemia, while in STZ-induced type 2-like diabetes, intravenous infusion of amylase prior to the IDGTT leads to a simultaneous decrease in the glucose curve and increased glucagon release, in an insulin-independent manner. The gene discussed is GCG; the disease is diabetes mellitus.