Insulin Action upon Insulin-Insensitive Tissue Following Impaired Degradation of the Hormone.

Abstract

Evidence that a retarded rate of insulin degradation results in a highly significant insulin effect upon the rat kidney is presented. The intravenous administration of alloxan to rats and removal of kidneys 10 min. later, or the in vitro incubation of rat kidney slices in alloxan for 10 min. prior to transfer of tissue slices and incubation in either 100 [mu]U 13 ll insulin/ml or 1000 [mu]U of stable insulin/ml results in markedly retarded insulin degradation and highly significant insulin enhancement of glucose uptake. Saline treated control animals fail to demonstrate an insulin effect. Comparable impairment of insulin degradation with development of biologic effect upon the kidney as noted with alloxan is also seen with tissue incubation at lowered incubation temperature (20[degree]C). These observations suggest that under appropriate conditions, tissue, heretofore believed to be insulin-insensitive, may be shown to respond to insulin.