Investigations on the frequency of chromosome aberrations in bone marrow cells of chinese hamsters after simultaneous application of caffeine and cyclophosphamide.

The potentiating effect of caffeine (1,3,7-trimethylxanthine) on chemically induced chromosome aberrations was studied in bone marrow cells of chinese hamsters, exposed to the alkylating agent cyclophosphamide. Four experimental series were performed: In the first two tests caffeine (200 mg/kg) or cyclophosphamide (40 mg/kg), respectively, were administered. A third and fourth test was performed with caffeine plus cyclophosphamide (200 + 40 mg/kg and 35 + 40 mg/kg, respectively) simultaneously. Aberrations induced by cyclophosphamide (40 mg/kg) were strongly potentiated by simultaneous application of caffeine (200 mg/kg) not only additively but even synergistically. This increase of aberrations cannot be found after injection of the lower dose of caffeine (35 mg/kg).