Abstract
In vitro perfused liver from rhesus monkey generated very low density lipoprotein (VLDL) similar to serum VLDL, except for the existance of three kinds of high molecular weight apoproteins. These three kinds of high molecular weight apoprotein were considered to be isoproteins of apoprotein B, because of their molecular weight, amino acid composition, and their immunological character. They were designated as B100, B74, and B42 in a centile system on SDS polyacrylamide gel electrophoresis.
Although the B42 ran a little bit faster than the B48 did, which was found in hyperlipemic monkey VLDL, it was considered that the B42 could be a modified B48.
Oleic acid supplement in perfusate resulted in the increase of triacylglycerol secretion in perfusate VLDL, indicating that fatty acid supplement results in the secretion of larger VLDL from perfusedliver.
The larger VLDL produced by the liver perfused with fatty acid supplement contained the more B42. Considering that the specific activity of B42 decreased with time over the course of perfusion, while that of B100 increased, the B42 is not considered to be degradative product of B100.
Besides, with increase of B42 in VLDL secreted by the liver perfused with fatty acid supplement, the ratio of apoprotein E to apoprotein B in VLDL increased, indicating that enlargement of VLDL secreted by the liver results in enrichment of apoprotein E and B42.
It is very important to explore the metabolic fate and the role in atherogeneity of such B42 and apoprotein E rich VLDL produced by fatty acid supplement.
