Influence of caffeine and 3-aminobenzamide in G2 on the frequency of chromosomal aberrations induced by thiotepa, mitomycin C and N-methyl-N-nitro-N'-nitrosoguanidine in human lymphocytes.

The effects of post-treatments with caffeine in G2 on the frequency of chromosomal aberrations induced by thiotepa, mitomycin C and N-methyl-N-nitro-N'-nitrosoguanidine were studied in human lymphocytes. Caffeine was found to potentiate the frequency of chromatid aberrations induced by all 3 S-dependent agents tested; the most striking enhancement being obtained when caffeine was present during the last 1.5 h before harvesting. Post-treatments in G2 with 3-aminobenzamide had no influence on the aberration frequency induced by thiotepa and N-methyl-N-nitro-N'-nitrosoguanidine.