[Cardiotoxic study of aclacinomycin A. Subacute cardiotoxic effect of aclacinomycin A in rats (author's transl)].
Subacut e cardiotoxic effect of aclacinomycin A or adriamycin given by daily intraperitoneal injections for 5 days was studied in rats by electrocardiography (ECG), blood biochemical analysis, light microscopy and electron microscopy. Dose levels of aclacinomycin A and adriamycin were 4 and 8 mg/kg, and 2 and 4 mg/kg, respectively. The two drugs caused severe body weight loss at a dose of 8 mg/kg and 4 mg/kg, respectively. Aclacinomycin A-treated rats at a dose of 4 mg/kg showed slight changes in ECG, whereas adriamycin-treated rats at the same dose showed a heart rate decrease, QRS duration and QT interval prolongation and R and S waves amplitude elevation. Blood biochemical changes caused by both drugs at a dose of 4 mg/kg were increased in lipoperoxide and alpha-hydroxybutyrate dehydrogenase activity. Aclacinomycin A gave slight ultrastructural changes in some cardiac cells such as formation of myelin figure and vacuolization in mitochondria. But adriamycin caused remarkable alterations such as degeneration and destruction of mitochondria, vacuolization of sarcoplasm and disappearance of myofilaments, which were often observed near the capillaries and nuclei. These results suggest that the two antibiotics caused cardiotoxicity by a similar mechanism. However, the damage produced by aclacinomycin A was milder than that of adriamycin.