Factors of Ehrlich Ascites Tumor resistance to oxidative stress.

Ehrlich Ascites Tumor (EAT) cells, compared to liver, were less susceptible to peroxidation (measured by the TBARS method) induced by Fe2+/ascorbate, ADP/Fe2+ and H2O2/Fe2+/ascorbate. Higher thiobarbituric acid reagent products TBARS levels were found with Fe2+/ascorbate or after ultrasonication induced peroxidation in lipids obtained from Ehrlich cells compared to EAT cell homogenate with the same lipid content. This suggests that non-lipid and structurally membrane antioxidants factors are of less importance for induction by Fe2+/ascorbate than by ultrasonication. The resistance to induced lipid peroxidation (LPO) in EAT cells is associated with the lower level of lipids, the lower double-bond index, the lower level of fatty acids reacting with TBA, as well as with the relatively higher level of alpha-tocopherol per mg lipid in the EAT cells as compared to the liver.