Zonal ultracentrifugation of plasma lipoproteins from normal and cholestatic pigs.

The plasma lipoproteins in normal and cholestatic pigs were isolated by zonal ultracentrifugation and studied with respect to apoprotein and lipid composition. In contrast with the distribution in human plasma, only one HDL-population but two LDL-populations were demonstrated. No cholestatic lipoprotein similar to the human lipoprotein X was observed. HDL and the lighter LDL component were largely unchanged in cholestasis. The immunochemical properties were changed to some extent. Thus HDL-reacting material was found in the heavier LDL-component and VLDL after cholestasis but not before.