Effect of insulin of glucose and glycogen metabolism and leucine incorporation into protein in cultured mouse astrocytes

Insulin, following binding to its receptor, produces a dose‐ and time‐dependent stimulation of entry of 2‐deoxy‐D‐[U‐ 14 C] glucose and glycogen synthesis from D‐[U‐ 14 C] glucose in cultured mouse astrocytes following differentiation. Maximal stimulation of both glucose entry (217% above basal) and of glycogen synthesis (209% above basal) was observed at an insulin concentration of 1.7 × 10 −8 M. Insulin also stimulates the incorporation of leucine into astrocytic proteins with maximal stimulation (156% above basal) at an insulin concentration of 1.7 × 10 −7 M, but no effect on leucine uptake was observed at an insulin concentration of 1.7 × 10 −6 M. These results, together with a previous demonstration that insulin and certain insulin analogues stimulate pyrimidine nucleoside incorporation into nucleic acid, indicate that insulin has diverse actions on biomacromolecular metabolism in cultured mouse astrocytes. © 1992 Wiley‐Liss, Inc.