RT Journal Article SR Electronic T1 Sulfoxide reduction. In vitro reduction of sulindac by rat hepatic cytosolic enzymes. JF Drug Metabolism and Disposition JO Drug Metab Dispos FD American Society for Pharmacology and Experimental Therapeutics SP 85 OP 87 VO 9 IS 2 A1 J H Ratnayake A1 P E Hanna A1 M W Anders A1 D E Duggan YR 1981 UL http://dmd.aspetjournals.org/content/9/2/85.abstract AB The reductive biotransformation of sulindac to the corresponding sulfide has been characterized in vitro in rat preparations with respect to subcellular and tissue distribution, cofactor requirements, kinetic constants, and the effects of inhibitors. The highest activity was found in hepatic and renal cytosolic fractions. Either NADPH or dithiothreitol effectively supported the reaction but NADH was much less effective. The KM and Vmax for sulindac were found to be 36.7 +/- 3.8 microM and 75.7 +/- 9.7 pmol/min/mg of protein, respectively, and the KM and Vmax for NADPH were found to be 0.48 +/- 0.03 microM and 43.3 +/- 4.6 pmol/min/mg of protein, respectively. The most effective inhibitors of the reaction were sulfhydryl reagents and sulfoxides structurally related to sulindac.