摘要
目的:观察缺血预处理对失血性休克血管反应性和钙敏感性的影响。方法:通过观察不同缺血预处理方法对失血性休克大鼠存活时间和24 h存活率的影响,选择最适缺血预处理方法。在体实验,观察缺血预处理对失血性休克大鼠肠系膜上动脉(SMA)血管管径对去甲肾上腺素(NE)收缩反应性和NE升压反应的影响;离体实验,应用离体血管环张力测定技术,观察缺血预处理对失血性休克后大鼠SMA环血管反应性和钙敏感性的影响。结果:确定最适缺血预处理方法为:夹闭腹主动脉1 min,开放5 min,重复3次,2 h后复制失血性休克模型,这种方法可显著增加失血性休克大鼠的存活时间和24 h存活率。在体实验,缺血预处理可显著增加休克晚期NE的升压效应和在体SMA对NE的收缩反应(P<0.01)。离体实验,与失血性休克对照组比较,缺血预处理组SMA在休克早期(休克即刻)对NE的收缩反应性和钙敏感性明显下降(P<0.05),但与正常对照组比较无显著差异(P>0.05);在休克后期(休克2 h、3 h、4 h),缺血预处理组SMA对NE的收缩反应性和钙敏感性显著增加(P<0.05),且与正常对照组比较无显著差异(P>0.05)。结论:缺血预处理可能通过改善血管钙敏感性发挥对休克后期血管反应性的保护效应。
AIM： To investigate the effect of ischemic preconditioning（IPC） on vascular reactivity and calcium sensitivity during hemorrhagic shock.METHODS： Appropriate method of IPC was selected by observing the effect of different strategies of IPC on the survival time and the survival rate in hemorrhagic shock rats.The effect of IPC on the pressor effect of norepinephrine（NE,3 μg/kg） and the contractile response of superior mesenteric artery（SMA） to NE and calcium in vivo and in vitro were observed.RESULTS： Among 3 strategies of IPC,3 cycles of abdominal aorta occlusion for 1 min and loosing for 5 min increased the survival time and 24 h survival rate significantly,which was superior to the other two IPC methods.In vivo,IPC significantly increased the pressor response to NE and the contractile response of SMA to NE（P〈0.01）.In vitro,IPC significantly improved the reactivity of SMA to NE and Ca2＋.The Emax values of SMA to NE and Ca2＋ in IPC group were significantly higher than that in shock control group（P〈0.01）.CONCLUSION： Ischemic preconditioning reverses Shock-induced vascular hyporeactivity via improving calcium sensitivity of the vasculatures.
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2011年第3期437-442,共6页
Chinese Journal of Pathophysiology
基金
国家杰出青年基金资助项目(No.30625037)
关键词
缺血预处理
休克
出血性
血管反应性
钙敏感性
Ischemic preconditioning
Shock
hemorrhagic
Vascular reactivity
Calcium sensitivity
