止血带缺血预处理对大鼠骨骼肌缺血再灌注损伤的保护作用--组织病理学研究

目的 :研究止血带缺血预处理对骨骼肌缺血再灌注损伤的保护作用和缺血时间梯度与再灌注时间梯度的关系。方法 :选择健康SD大鼠 12 0只 ,随机分成缺血预处理组 (实验组 )和非预处理组 (对照组 )。每组再分为缺血 2小时、3小时、4小时 3个小组 ,每小组 2 0只。用特制的气囊止血带制成大鼠后肢缺血再灌注损伤模型 ,通过连续切片观察预处理组与非预处理组大鼠胫前肌和股四头肌在不同缺血时间及不同再灌注时间发生的病理变化 ,评价止血带缺血预处理对大鼠骨骼肌缺血再灌注损伤的保护作用 ,探讨缺血时间梯度与再灌注时间梯度的关系。结果 :缺血 2小时 ,预处理组与非预处理组骨骼肌病理变化轻 ,保护作用不明显。缺血 3小时 ,两组均发生明显病理变化。无论在炎细胞浸润 ,还是肌细胞变性坏死 ,对照组均明显重于实验组 ,保护作用显著。缺血 4小时 ,两组病理损害十分严重 ,保护作用不如缺血 3小时明显。从再灌注第 1、3、7、14天的病理结果比较发现 ,再灌注第 3天时病理损伤最重 ,保护作用最明显。结论 :止血带缺血预处理对骨骼肌缺血再灌注损伤具有明显保护作用 ,尤其对缺血 3小时再灌注 3天时保护作用最显著 ,缺血超过一定时间则保护作用不明显

The Protective Effects of Ischemia Preconditioning with Pneumatic Tourniquet on Ischemia and Reperfusion Injury of Skeletal Muscle in Rat

objective To study the protective effects of ischemic preconditioning with pneumatic tourniquet on ischemia and reperfusion injury of skeletal muscle of rat and to explore the relationship between the time gradient of ischemia and reperfusion. Methods 120 healthy SD rats were selected and randomly divided into an ischemic preconditioning (experiment) group and no preconditioning (control) group equally in this experiment. The ischemia and reperfusion injury was made by blocking the blood flows of the rat hind limb with a pneumatic tourniquet. The skeletal muscle pathological changes of both groups were observed in different time of ischemia and reperfusion with section consecutively. The protective effects of ischemia preconditioning with pneumatic tourniquet on ischemia and reperfusion injury to rat skeletal muscle were assessed and the relationship between the gradient time of ischemia and reperfusion as well. Results Both groups comparing with the pathological changes of reperfusion injury in the 1st, 3rd, 7th, and 14th day, the result showed that ischemia preconditioning with pneumatic tourniquet had the best protective effect to rat skeletal muscle on ischemia and reperfusion injury for 3 hours in ischemia. Conclusion Ischemia preconditioning with pneumatic tourniquet has obvious protective effects to ischemia and reperfusion injury, the best protective effect appears in ischemia for 3 hours and reperfusion for 3 days.