Differential cytotoxicity of sodium arsenite in human fibroblasts and Chinese hamster ovary cells.
Human skin fibroblast (HF) cells were approximately 10-fold more sensitive to sodium arsenite toxicity than Chinese hamster ovary (CHO) cells using the clonogenic assay. G1-phase CHO cells showed a 2-fold increase in the susceptibility to the toxic effects of sodium arsenite as compared to asynchronous CHO cells. The concentrations of sodium arsenite required to kill 50% of the cell population were correlated with the intracellular glutathione levels in asynchronous, G1-phase CHO, and asynchronous HF cells. Moreover, verapamil potentiated the cytotoxicity of sodium arsenite in CHO cells but not in HF cells. These results indicated that a verapamil-sensitive outward channel may be involved in detoxification of arsenic in CHO cells. Treatment with sodium arsenite resulted in a marked cell-cycle disturbance in CHO, but not in HF cells. Thus, CHO cells may take time to recover from sodium arsenite insult before progressing through the cell cycle. A different response of sodium arsenite in heat-shock protein synthesis in these 2 cell types was also revealed.
Lee
T C
TC
Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan, R.O.C.
Ko
J L
JL
Jan
K Y
KY
D000818:Animals; D001151:Arsenic / Q000633:toxicity*; D018053:Arsenites; D002453:Cell Cycle / Q000187:drug effects; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects*; D005978:Glutathione / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000096:biosynthesis; D006801:Humans; D017670:Sodium Compounds; D014700:Verapamil / Q000494:pharmacology
D018053:Arsenites; D006360:Heat-Shock Proteins; D017670:Sodium Compounds; C017947:sodium arsenite; D014700:Verapamil; D005978:Glutathione; D001151:Arsenic