PALMITATE UPTAKE BY HEPATOCYTE SUSPENSIONS - EFFECT OF ALBUMIN

The clearance ratio test has been used to determine whether hepatocyte s isolated from female rat livers facilitate the dissociation rate of albumin-palmitate complexes. This test requires knowledge of the clear ance rate and unbound palmitate fraction at two protein concentrations . The unbound fractions have been estimated using the heptane-water pa rtition ratio method. These fractions were determined to deviate from the expected linear relationship because of radiolabeled impurities th at were still present after purification of the [H-3]palmitic acid. Wi th the use of experimentally determined partition ratio values, the pa lmitate clearance ratios were statistically greater than those predict ed by the diffusion-reaction model at albumin concentration combinatio ns above 99 mu M/49 mu M. Experimental clearance rates also exceeded t hose predicted by the diffusion-reaction model, but only at albumin co ncentrations greater than 198 mu M. These data support the proposal th at hepatocytes facilitate the dissociation of albumin-palmitate comple xes at high albumin concentrations.