EFFECT OF RESIDUAL ENZYMES ON DEGRADATION OF RADIOIODINATED VLDL BY COLLAGENASE-DISPERSED HEPATOCYTES

Liver cells isolated with crude collagenase rapidly catabolized radioiodinated VLDL. The hepatocytes retained proteolytically active elements of the preparative enzymes. Both collagenase in the absence of cells and hepatocytes prepared with collagenase degraded the C-apoproteins of labeled VLDL. Hepatocytes isolated with a chelating agent in place of collagenase deiodinated, but did not catabolize [125I] labeled VLDL. Similarly prepared cells degraded labeled HDL, but addition of collagenase to incubations greatly enhanced this process. Therefore, data on hepatic catabolism of serum lipoproteins obtained with hepatocytes freshly prepared with collagenase must be interpreted with caution. © 1979.