Abstract
Brief incubation of isolated rat hepatocytes in the presence of the oleate-bovine serum albumin complex resulted in a release to the cytosol of a portion of hexokinase (EC 2.7.1.1) normally bound to intracellular membranes. This was correlated with an increase of the negative surface potential of the outer mitochondrial membrane, as measured in situ by determining changes of Km of monoamine oxidase (EC 1.4.3.4). It is suggested that non-esterified fatty acids produce a partial release of bound hexokinase in the liver cell by changing the surface charge of intracellular membranes.