Characterization of an [ 125I]-Insulin binding plasma membrane fraction from rat liver

Abstract

A procedure for the isolation of three different plasma membrane fractions from rat liver is described. The heavy subfraction (PL 1) has a high specific activity in alkaline phosphatase, while the lightest subfraction (PL 3) contains a high specific activity in 5′-Nucleotidase, ATPase and phosphodiesterase. The major part of the plasma membrane recovered is found in PL 3. A specific binding of [ 125I]-Insulin is shown to occur in PL 3, with a ten-fold enhancement over that of any other plasma membrane fraction.