Fig 4.

Metronidazole (MTZ) genotoxicity on PBMC and feline lymphoma cells. (A) MTZ induced DNA damage in both PBMC and 3201 lymphoma cells, as assessed by COMET assay, at all concentrations tested. c=Number of comets, v=number of viable cells. (B) Silver stain of gel electrophoresis of control PBMC (no drug exposure). (C) Silver stain of gel electrophoresis of PBMC exposed to 100 μg/ml MTZ. (D) Silver stain of gel electrophoresis of PBMC exposed to H₂O₂ (positive control). Comet tails can be clearly seen in panels (C) and (D). 60× magnification.