Effect of tetracycline on adriamycin cardiotoxicity.

Male rats were treated with either adriamycin (2 mg/kg, i.v. weekly) or adriamycin and tetracycline (10 mg/kg, i.p., daily) for 8 weeks. Serum creatine phosphokinase (CPK) activity was measured after 8 weeks as an index of cardiotoxicity. Serum CPK was significantly elevated in the adriamycin-treated rats. Tetracycline failed to inhibit the adriamycin-induced increase in serum CPK. These results indicated that tetracycline does not prevent adriamycin-induced cardiotoxicity.