Insulin acutely increases phospholipids in the phosphatidate-inositide cycle in rat adipose tissue.

Administration of insulin in vivo provoked rapid (near maximal in 30 min) increases (65-90%) in the concentrations of phosphatidic acid, phosphatidylinositol, and polyphosphoinositides in rat adipose tissue. Insulin also increased phosphatidylinositol levels in adipocytes incubated in vitro. Dose-response relationships suggested that these effects of insulin were physiologically relevant. The enrichment of membranes with acidic phospholipids in the phosphatidate-inositide cycle may play a role in the action of insulin in adipocytes.