A COMPARISON OF RADIOSENSITIZING EFFECT ON SOLID TU- MOR IN MICE BETWEEN METRONIDAZOlE AND ITS DERIVA-TIVE / 第二军医大学学报

ABSTRACT

This paper compares the radiosensitizing effect of metronidazole(M) with that of its derivatives(CM)on sarcoma 180 (S180).After i.p injection S180 bearing mice were either irradiated with y-ray 17Gy or unirradiated under aerated or tumor acute local hypoxic conditions.Results indicate that under hypoxic condition tumor growth Was inhibited within 10 d after a single i.p injection of drugs, but under aerated condition inhibition of tumor growth did not occur.CM was found to be stronger than M in tumor inhibiting effect.After aerated irradiation the drug groups demonstrated an apparent slowing down of tumor growth.But the difference between groups was not obvious.Hypoxic irradiation produced a very strong inhibiting effect in the drug groups.CM, especially when it was chelated with Ca++to form CMCa, was strongest in tumor growth inhibition.Its tumor inhibiting ratio was 77.4%, enhancement ratio(ER)2.46 and sensitizing enhancement ratio(SER)1.89.Its tumor inhibiting effect was stronger than irradiation without drug administration and irradiation after the administration of M.Its radiossnsitizng effect was found to be twice stronger than that of the original compound(M), but its toxic side effect was slighter than M.