LLN对大鼠急性心肌缺血损伤的作用及作用机制研究

The protection of LLN on acute myocardial injury in rats

目的:探讨中药成分LLN对大鼠急性心肌损伤的保护作用。方法:用异丙肾上腺素(ISO)30mg/kg两次注射造成大鼠心肌损伤模型,LLN大(400mg/kg)、中(200mg/kg)、小剂量组(100mg/kg)及丹参酚酮(400 mg/kg)灌胃,观察对急性心肌损伤的大鼠心电图△J的变化,计算心脏指数,测定血清CK和LDH,同时测定心肌匀浆中Na+-K+-ATPase、Ca2+-ATPase、Mg2+-ATPase活性。结果:ISO模型组心肌系数和血清CK、LDH显著升高;Na+-K+ATPase、Ca2+-ATPase、Mg2+-ATPase的活性显著下降。与模型组比,LLN各剂量组和丹参组心电图△J降低,心脏系数和血清CK、LDH显著下降,Na+-K+-ATPase、Ca2+-ATPase、Mg2+-ATPase的活性升高。结论:LLN对异丙肾上腺素造成的急性心肌损伤具有保护作用,其保护机制与提高Na+-K+-ATPase、Ca2+-ATPase、Mg2+-ATPase活性,减轻细胞内钙超载有关。

Objective：To study the protection and possible mechanisms of LLN in acute myocardial injury in rats.Methods： Acute myocardial injury induced by hypodermic injecting isoprenaline（ISO）.SD rats were divided into six groups at random.They were control group,the ISO group（NS 10ml/kg ＋ ISO 30mg/kg·d）,the LLN group（400mg/kg ＋ ISO 30mg/kg·d）,the LLN group（200mg/kg ＋ ISO 30mg/kg·d）,the LLN group（100mg/kg ＋ ISO 30mg/kg·d） and the Danshen group（400mg/kg ＋ ISO 30mg/kg·d）.The effect of LLN in myocardium was observed by△J of ECG and measured by cardiac index.The activities of Na＋-K＋ATPase,Ca2＋-ATPase and Mg2＋-ATPase were measured.Results： In the ISO group,compared with the control group,cardiac index and CK,LDH content in serum were higher.The activities of Na＋-K＋ATPase,Ca2＋-ATPase and Mg2＋-ATPase were decreased.In the LLN group and the Danshen group,the cardiac index,△J of ECG and CK,LDH content in serum of rats injured by ISO were relieved.The activities of Na＋-K＋-ATPase,Ca2＋-ATPase and Mg2＋-ATPase were higher than those in the ISO group.Conclusion： The LLN can alleviate rat myocardium from acute ischemic injury by isoprenaline,one of the mechanisms is to inhibit the overload of Ca2＋ in ischemia cardiac muscle cells by increasing the activities of Na＋-K＋-ATPase,Ca2＋-ATPase and Mg2＋-ATPase.