HMG-CoA reductase activity in human liver microsomes: comparative inhibition by statins

The aim of this study was to compare a number of vastatins, HMG-CoA reducta se inhibitors, in human liver microsomes. HMG-CoA reductase activity was fo ur times lower than the activity in untreated rat liver microsomes. Vastati ns could be classified in this in vitro assay in three classes both in huma n and rat microsomes: the first one including cerivastatin with an IC50 of 6 nM, the second one with atorvastatin and fluvastatin (IC50) between 40 an d 100 nM) and the third one containing pravastatin, simvastatin and lovasta tin (IC50 between 100 and 300 nM).