Lipitor, also known as atorvastatin, is a medication commonly prescribed to lower cholesterol levels and reduce the risk of heart disease [1]. While its primary mechanism of action is related to cholesterol metabolism, there is limited information available regarding Lipitor's direct effects on protein metabolism.

Lipitor inhibits HMG-CoA reductase, an enzyme that plays a crucial role in the production of cholesterol in the liver [1]. By inhibiting this enzyme, Lipitor reduces the amount of cholesterol synthesized in the liver, which in turn increases the number of LDL (low-density lipoprotein) receptors on the surface of liver cells [1]. This results in an increased clearance of LDL cholesterol from the bloodstream.

As for protein metabolism, Lipitor's effects are indirect and not well-studied. Cholesterol is a precursor for the synthesis of steroid hormones, bile acids, and vitamin D [1]. Therefore, by affecting cholesterol metabolism, Lipitor could potentially influence the production of these compounds, which may have downstream effects on protein metabolism. However, specific research on Lipitor's impact on protein metabolism is scarce.

In summary, Lipitor's primary effects are on cholesterol metabolism, and its impact on protein metabolism is indirect and not extensively researched [1].

Sources:
[1] DrugPatentWatch.com - Lipitor (atorvastatin) - <https://www.drugpatentwatch.com/drugs/lipitor>