Muscle response to insulin in fetuses of diabetic pregnant rats.

Abstract

To elucidate the effect of nutrition during induction on peripheral muscle responsiveness to insulin, the incorporation of radiolabeled glucose to glycogen and the uptake of radiolabeled deoxyglucose were studied in isolated diaphragms from the fetuses of normal and diabetic pregnant rats in vitro. Basal- and insulin-stimulated incorporation of [1-14C]glucose into diaphragm glycogen were greater in the fetuses of diabetic mothers (IDM) than in normal fetuses, but there was no difference in the degree of stimulation by insulin of labeled glucose into glycogen between normal fetuses and IDM. Diaphragms from normal fetuses and IDM had the same basal up ake of 2-deoxy-[1-3H]glucose as well as insulin-stimulated uptake. Consequently the sensitivity of glucose uptake to insulin was similar both in normal fetuses and IDM. These data indicate that glucose utilization (incorporation of labeled glucose into glycogen) was increased in IDM, but that the response of glucose uptake and glycogenesis to insulin was not altered.