A study of toxicity of 5-fluorouracil on bovine trabecular meshwork cells in vitro.

In order to explore whether the conventional use of 5-fluorouracil (5-Fu) had any toxic effects on trabecular meshwork cells, bovine trabecular meshwork cells were cultured in vitro and exposed to 5-Fu at different concentrations. The cellular morphology, ultrastructure, mortality and phagocytosis were studied under light microscopy, transmission electron microscopy and methods of Wright's stain. It was found that the toxic effects of 5-Fu on the cells were in a dose-dependent mode. 1 x 10(-1) mg/ml of 5-Fu caused a large part of cells rounded up, while 1 x 10(-2) mg/ml of the drug only a rough appearance of the cell surface. Exposure to 1 x 10(-2) mg/ml of 5-Fu made mitochrone swollen and rough endoplasmic reticulum enlarged, with the cell mortality being 50.5%. The latex microspheres engulfed in cytoplasm in cells receiving 1 x 10(-1) and 1 x 10(-2) mg/ml of 5-Fu were significantly decreased as compared with those in the control group (P < 0.01). It was concluded that the safe concentration of 5-Fu on bovine trabecular meshwork cells was 1 x 10(-2) mg/ml and the conventional dosage of 5-Fu in clinical practice would not cause injury to trabecular meshwork cells.