Effect of benfluron metabolites on ATP level in tumor cells.

Changes in ATP levels of both Ehrlich ascites carcinoma and P388 leukemia cells were evaluated after 2 h of incubation in the presence of different concentrations of benfluron (BF), 7-dihydrobenfluron (DBF) and N-oxide of benfluron (NOBF). Up to the concentration of 37.5 mumol/l, none of the substances significantly depressed the ATP levels. A more expressive decrease in ATP levels was noted only at concentrations of 75 mumol/l and higher. BF proved the most effective, less effective was DBF, while NOBF was practically without any effect. Of the remaining cytostatic drugs, Mitoxantrone, CCNU and Me-CCNU, in particular, proved efficient in depressing ATP level. The latter becomes depressed already after 15 min of incubation in the presence of the highest concentrations of benfluron and 7-dihydrobenfluron.