Comparative studies of the circulating lipoproteins in hamster (Mesocricetus auratus) with a normal or spontaneous high level of cholesterol in the plasma.

The lipoprotein profile and the distribution of plasma cholesterol were studied comparatively in two strains of hamster, a normal one, and a second, developing spontaneous hypercholesterolemia associated with a high level of cholesterol esters in the liver. In the hypercholesterolemic animals, the amount of cholesterol was increased by 40, 84 and 69% in the circulating VLDL, LDL and HDL respectively. Moreover, the VLDL were particularly rich in cholesterol esters, 21% of their weight in contrast to 11% in controls. A close positive correlation existed between the enrichment of the VLDL with the esters and the accumulation of cholesterol in the hepatic tissue. In the two strains of hamster, there was similar participation of the various classes of lipoprotein in cholesterol transport, that of HDL being particularly high. These lipoproteins carried more than 50% of the circulating cholesterol.