Lipoprotein fractions and receptors: a role for XXXX ?

@entity754 @entity6741 @entity5119 @entity2453 @entity165
@entity165 transport in the plasma involves several lipoprotein families. The process is remarkably ordered and is driven vectorily by apolipoproteins, which activate appropriate enzymes or serve as recognition sites for lipoprotein receptors. Of the lipoproteins in plasma, low density lipoprotein (LDL) contains most of the @entity165 and has the greatest atherogenic potential. Its plasma concentration is determined by @entity754 activity, which serves to regulate intracellular @entity165 concentrations. @entity754 activity in the body is not fixed, but can be stimulated by drugs that affect hepatic @entity165 content, such as inhibitors of @entity2453 reductase or @entity6741 sequestrants. By stimulating @entity754 activity, these drugs increase the fractional catabolic rate of apoLDL. @entity2453 reductase inhibitors also appear to reduce the apoLDL synthetic rate. As a consequence, LDL @entity165 levels are reduced while high density lipoprotein (HDL) @entity165 levels remain stable or increase. @entity5119 is a drug that lowers both LDL and HDL @entity165 levels. It appears to lower LDL @entity165 levels by affecting LDL structure rather than by stimulating @entity754 activity. It has no consistent effect on LDL synthetic rates. @entity5119 lowers plasma HDL @entity165 levels by decreasing the synthetic rates of the major HDL apolipoproteins. The biologic significance of these @entity5119 -induced changes in HDL metabolism is unknown.
