Evaluation of vitamin E and selenium protection against chronic adriamycin toxicity in rabbits.

Chronic Adriamycin (ADR) toxicity was produced in 50 weanling rabbits by weekly injections of 2.4 mg of ADR/kg of body weight for up to 17 weeks. An evaluation was made of the protective value of weekly injected supplements, given 24 hours before each ADR injection, which included: (a) low-dose vitamin E (alpha-tocopherol acetate, 17 mg/kg) (b) high-dose vitamin E (alpha-tocopherol acetate, 170 mg/kg); (c) selenium (as sodium selenite, 0.06 mg/kg); and (d) combined low-dose vitamin E and selenium. The incidence of cardiomyopathy was high in both supplemented and unsupplemented rabbits. Mean cardiomyopathy scores were low in the unsupplemented rabbits and moderatey high in the supplemented rabbits (that survived longer), but were lower in rabbits given high-dose vitamin E than in the other supplemented groups. Supplements of vitamin E, selenium, or both prolonged survival of animals treated continuously with ADR, but only supplements of large amounts of vitamin E provided any evidence of even partial protection against chronic cardiotoxicity.