The evaluation of prooxidant and antioxidant state of two variants of lewis lung carcinoma: a comparative study.

AIM To study the functional activity of enzymatic component of antioxidant system and to evaluate an intensity of prooxidative processes in Lewis lung carcinoma variants (LLC and LLC/R9). METHODS Activity of glutathione-S-transferase (GST), glutathione peroxidase (GP), glutathione reductase (GR), catаlase (Cat), content of lipid peroxidation (LP) byproducts were analyzed in tumor extracts at the 24(th) day after tumor transplantation, extracts of muscle tissues of tumor-bearing mice and intact mice using the method of optic spectrometry. RESULTS It was revealed higher level of GST and GR activities, and lower level of GP activity, and a tendency for decrease of Cat activity level in LLC/R9 tumors compared to LLC tumors. The content of primary LP products was higher in LLC/R9 tumors while two tumor variants didn't differ significantly by the content of tiobarbiturate-active products. CONCLUSION The pool of reduced glutathione in LLC/R9 tumors is more effectively replenished with GP involvement and is used by GST for detoxification of exogenous xenobiotics compared with LLC. Lower GP activity and the tendency to decreased Cat activity is characteristic property for LLC/R9 tumors compared to LLC.