目的研究胰岛素样生长因子－Ｉ（ＩＧＦ－Ｉ）对异丙肾上腺素（ＩＳＰ）致大鼠心肌损伤丙二醛（ＭＤＡ），谷 胱甘肽过氧化物酶（ＧＳＨ－Ｐｘ）的变化影响。方法采用大鼠ＩＳＰ心肌损伤动物模型，以ＩＧＦ－Ｉ作保护因素，分别检 测ＭＤＡ的含量及全血．ＧＳＨ－Ｐｘ的活力。结果ＩＳＰ组大鼠全血ＧＳＨ－ＰＸ活力明显低于ＩＧＦ－Ｉ＋ＩＳＰ组。结论 ＩＧＦ－Ｉ能减少 ＩＳＰ所致心肌损伤时氧自由基的产生，减轻氧自由基对细胞膜的直接损害作用；同时 ＩＧＦ－Ｉ还能提 高内源性抗氧化酶的活性，从而加强内源性自由基的清除能力。 Objective To investigate the effects of insulin-like growth factor-I (IGF-I) on the changes of malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) in rats with isoproterenol (ISP) Methods The animal model of myocardial injury was established in rats. IGF-I was used as the protective factor to detect the content of MDA and whole blood respectively. The vitality of GSH-Px. Results The GSH-PX activity in whole blood of ISP group was significantly lower than that of IGF-I + ISP group. Conclusion IGF-I can reduce the production of oxygen free radicals in myocardial injury induced by ISP and reduce the direct damage of oxygen free radicals to the cell membrane. Meanwhile, IGF-I can enhance the activity of endogenous antioxidant enzymes and enhance the endogenous Free radical scavenging ability.