Effect of CPT-11 on lipid peroxide level in mouse tissues.

We examined the effects of CPT-11 on lipid peroxide level and glutathione peroxidase (GSHpx) activity as indices of the toxicity of this antitumor agent in mouse and rat tissues. After CPT-11 (100 mg/kg, i.p.) administration, the lipid peroxide level in the heart increased 1.5 fold (mice) and 1.3 fold (rats) over the control levels. GSHpx activity decreased to 64% of the control. In the lung, the lipid peroxide level and GSHpx activity increased 2.5 fold and decreased to 74% after CPT-11 administration, respectively, compared with the control values. These results suggested that CPT-11 may cause cardiotoxicity and pulmotoxicity. In rat bone marrow, the lipid peroxide level increased on the 2nd day after CPT-11 injection. We suggest that in both single and combination treatment with CPT-11, the possibility of side effects should be taken into consideration.