In this study, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) were used to determine the inhibition of arylamine N-acetyltransferase (NAT) activity and DNA adduct formation in human bladder tumour cell line T-24. The activity of NAT was measured by high-performance liquid chromatography, assaying for the amounts of N-acetyl-2-aminofluorene and N-acetyl-p-aminobenzoic acid and remaining 2-aminofluorene and p-aminobenzoic acid. Human bladder tumour cell line T-24 cytosols and intact cells were used for examining NAT activity and carcinogen-DNA adduct formation. The results demonstrated that NAT activity and 2-aminofluorene-DNA adduct formation in human bladder tumour cells were inhibited and decreased by BHA and BHT in a dose-dependent manner. The effects of BHA and BHT on the values of the apparent K-m and V-max also were determined in both systems examined. The results indicated that BHA and BHT decreased the apparent values of K-m and V-max from human bladder tumour cells in both cytosol and intact cells. Copyright (C) 2002 John Wiley Sons, Ltd.
