关键词: 心肌, 细胞学, 过氧化氢, 一氧化氮

Abstract: To investigate the protective effects of Astragaloside Ⅳ(ASⅣ )on cardiomyocytes against hydrogen peroxide(H₂O₂)-induced injury. Methods Cultured neonatal rat cardiomyocytes were divided into control group;0.1%DMSO solven group；H₂O₂ group, in which cells were treated with H₂O₂ ( 0.2　 mmol•L^-1) for 24 h;ASⅣ+H₂O₂ groups, in which cells were pretreated with ASⅣ (with final concentration of 3,10,30 mg•L^-1) for 30 min before H₂O₂ treatment; Astragaloside injection group (150　g•L^-1 ).Morphological changes of myocardial cells damaged for 24 h by 0.2 mmol•L^-1 H₂O₂ under the inverted microscope were observed. The cardiomyocyte viability was analysed by MTT assay; lactate dehydrogenase (LDH) activity, superoxide dismutase ( SOD) activity, malonaldehyde (MDA) content and nitric oxide (NO) content were detected in culture media. Results Most of cells in H₂O₂ group were crenulated,the nucleus were dim and the pseudopodia were disappeared. The degrees of lesion in ASⅣ (3,10, 30　mg•L^-1) groups were lessened obviously, the nucleus were bright and the the pseudopodia were thinned slightly. Cardiomyocyte viabilities in ASⅣ (3,10, 30　mg•L^-1) groups were higher than that in H₂O₂ group (P<0.05 or P<0.01).LDH activity and MDA content in ASⅣ (10, 30 mg•L^-1)groups were lower than those in H₂O₂ group (P<0.05 or P<0.01), and SOD activity and NO content in ASⅣ (10, 30 mg•L^-1)groups were higher than those in H₂O₂ group (P<0.05 or P<0.01). Conclusion ASⅣ can protect cardiomyocytes from H₂O₂ injury by improving cell antioxidant ability and increasing NO content.

Key words: myocardium, cytology, hydrogen peroxide, nitric oxide