Objective To explore the protective effects of flavonoids of Apocynum venetum L on adriamycin-induced cardiotoxicity in rats.
Methods In the experiment, rats were randomly divided into seven groups: 1. control group (CON), 2. model group (ADR), 3. preventive positive medicine control group (P-VC), 4. treament positive medicine control group (T-VC), 5. preventive low dose of LBM groups (P-LBM-L), 6. preventive high dose of LBM groups (P-LBM-H), 7.treament low dosage of LBM groups (T-LBM-L). After oral administration of flavonoids 10 days, the RM6240 system was applied to measure the index of cardioc output in rats, e.g. LVSP, LVEDP and ±dp/dtmax.. All rats were taken the electrocardiogram examination, e.g.HR, QRS, R wave. The content of myocardial SOD and surem SOD were messured by hydroxylamine method. The content of myocardial MDA and surem MDA were messured by TBA method.
Results Compared with model group, both P-LBM and T-LBM group incread HR, shortening QRS and incread R wave (P < 0.05). Both P-LBM and T-LBM group incread LVSP and dicread LVEDP (P < 0.05). Both P-LBM and T-LBM group incread ± dp/dtmax (P < 0.05). Both P-LBM and T-LBM group incread surem SOD and dicread surem MDA (P < 0.05). Both P-LBM and T-LBM group incread myocardial SOD and dicread myocardial MDA (P < 0.05). Light microscopy of heart tissue from rats. There were histological changes in the ADR group. ADR-induced cardiac damage was recognised by the presence of marked interstitial oedema, focal subendocardial fibrosis, perinuclear vacuolation, disorganisation and degeneration of the myocardium. In the heart tissue, normal histological findings were seen in the P-LBM and T-LMB group.
Transmission electron microscopic observations of myocardial cells in rat treated with ADR. The cytoplasm contains abnormal vesicles and has some marginal chromatins along the nuclear membrane. Mitochondrial distension with loss of cristae and electron dense materials are also visible. However, myocardial cells from control show normal morphological features. The myocardial cells of rat treated with P-LBM and T-LMB shows nearly normal ultrastructural features.
Conclusions Flavonoids of Apocynum venetum L has protective effects on adriamycin-induced cardiotoxicity in rats, which is probably associated with scavenging free oxygen radicals and anti-lipoperoxidation.