Interrelationship between serum -lipoprotein and cholinesterase.

The possible association between serum β-lipoproteins and cholinesterase was investigated in vivo after artificial induction of hyperlipidemia in rabbits, resulting from the injection of the lipopolysaccharide of Escherichia coli (E. coli endotoxin), and in vitro by following the action of phospholipase D upon isolated human serum β-lipoprotein.A marked increase in serum pre-β-lipoproteins (VLDL) was found to occur within 24 h after the injection of E. coli endotoxin in rabbits. In the next 48–72 h, a marked reduction in pre-β- (VLDL) concomitant with a marked increase in β- (LDL) and α- (HDL) lipoproteins was observed. A sharp increase in cholinesterase isoenzyme activities was visualized (starch gel zymogram) with the development of hyper-pre-beta-lipoproteinemia and decrease with hyper-beta-lipoproteinemia.When isolated serum β-lipoproteins were incubated with phospholipase D for 24 h at 37 °C, release of cholinesterase associated with a decrease in β-lipoprotein concentrations along with the formation...