Abstract

A GC assay method for haloperidol reductase was developed. Haloperidol reductase was present in guinea pig liver cytosol as well as in the microsomes, while in human liver only the cytosol exhibited the activity. The reductase activity was NADPH dependent for both species. Known substrates of ketone reductase such as menadione, daunorubicin, and ethacrynic acid strongly inhibited the human haloperidol reductase. The haloperidol reductase showed characteristics of ketone reductase.