Simvastatin

Simvastatin is a derivative of lovastatin and potent competitive inhibitor of 3-hydroxy-3-methylglutaryl coenzyme a reductase (hydroxy methylglutaryl coa reductases), which is the rate-limiting enzyme in cholesterol biosynthesis. It may also interfere with steroid hormone production. Due to the induction of hepatic ldl receptors, it increases breakdown of ldl cholesterol. Simvastatin is a hmg-coa reductase inhibitor. The mechanism of action of simvastatin is as a hydroxy methylglutaryl-coa reductase inhibitor.
Simvastatin is a lipid-lowering agent derived synthetically from a fermentation product of the fungus aspergillus terreus. Hydrolyzed in vivo to an active metabolite, simvastatincompetitively inhibits hepatic hydroxymethyl-glutaryl coenzyme a (hmg-coa) reductase, the enzyme which catalyzes the conversion of hmg-coa to mevalonate, a key step incholesterol synthesis. This agent lowers plasma cholesterol and lipoprotein levels, and modulates immune responses by suppressing mhc ii (major histocompatibility complex ii) on interferon gamma-stimulated, antigen-presenting cells such as human vascular endothelial cells.