Atorvastatin (Axon 2043) is probably among the best knows inhibitors of the enzyme HMG-CoA reductase (EC 1.1.1.88), an enzyme found in liver tissue that plays a key role in the mevalonate pathway, the metabolic pathway that produces cholesterol and other isoprenoids. Inhibition of the enzyme decreases de novo cholesterol synthesis, increasing expression of low-density lipoprotein receptors (LDL receptors) on hepatocytes. This increases LDL uptake by the hepatocytes, decreasing the amount of LDL-cholesterol in the blood. Interestingly, like most drugs, degradation of Atorvastatin is initiated by another oxidoreductase enzyme: Cytochrome P450 3A4 (CYP3A4), an enzyme in the class of EC 1.14.