Effect of caffeine in G2 on X-ray-induced chromosomal aberrations and mitotic inhibition in ataxia telangiectasia fibroblast and lymphoblastoid cells.

The effect of post-treatments with caffeine in G2 on the frequency of X-ray-induced chromatid aberrations was studied in normal and ataxia telangiectasia (A-T) fibroblast and lymphoblastoid cells. Caffeine was found to potentiate the X-ray-induced aberration yield in both normal fibroblast and lymphoblastoid cells. An enhancement was also observed in A-T lymphoblastoid cells, whereas the X-ray-induced aberration frequency in A-T fibroblasts was unaffected by the presence of caffeine. The influence of caffeine on the radiation-induced mitotic inhibition was investigated in normal and A-T fibroblasts; in both types of cell less inhibition was obtained in the presence of caffeine.