RT Journal Article SR Electronic T1 The effect of etomidate on rabbit liver microsomal drug metabolism in vitro. JF Drug Metabolism and Disposition JO Drug Metab Dispos FD American Society for Pharmacology and Experimental Therapeutics SP 364 OP 367 VO 13 IS 3 A1 Y Horai A1 P F White A1 A J Trevor YR 1985 UL http://dmd.aspetjournals.org/content/13/3/364.abstract AB Etomidate, an imidazole-containing anesthetic agent, is shown to be a reversible inhibitor of rabbit liver microsomal enzymes in vitro. Inhibition of aniline hydroxylation by etomidate follows competitive kinetics, while inhibition of microsomal N-demethylase and O-demethylase activities is of the mixed type. The concentrations of etomidate required to cause 50% inhibition of these enzyme activities are in the 7-10 microM range. NADPH-cytochrome c reductase is not inhibited by concentrations of etomidate below 100 microM. Spectrophotometric studies show that the addition of etomidate to liver microsomes results in a type II binding spectrum. We suggest that etomidate binds with high affinity to cytochrome(s) P-450, resulting in the inhibition of liver drug metabolism.