Yield of SCEs and translocations produced by 3 aminobenzamide in cultured Chinese hamster cells.

Different concentrations of 3-aminobenzamide (3AB), a strong inhibitor of poly(ADP-ribose) polymerase (PARP), were used to study their effect on the BrdU-substituted DNA of the Chinese hamster AA8 cell line. The frequencies of sister chromatid exchanges (SCEs) and translocations were determined using the fluorescence plus Giemsa (FPG) and fluorescence in situ hybridization (FISH) techniques, respectively. The results indicate that 3AB effectively induced a dose-dependent increase in the frequency of SCEs, but this enhancement in the yield of SCEs was not paralleled by an increase in translocations. These results are discussed in terms of the as yet poorly understood molecular mechanisms of action of the enzyme PARP.