酸处理对老龄大鼠心肌缺血再灌注后血流动力学的影响

Effects of acidosis on cardiac hemodynamics in aged rat heart after reperfusion injury

目的:观察短暂延迟性酸处理对老龄大鼠心肌缺血再灌注后血流动力学的影响。方法:60只SD老龄大鼠(≥18个月),随机分为6组(n=10):(1)空白对照(C组)组;(2)缺血再灌注(I/R)组;(3)缺血后处理(IPO)组;(4)酸处理(H+)组;(5)缺血后处理+碱处理(IPO+OH-)组;(6)碱处理(OH-)对照组。采用Langendorff离体心脏灌流方法,以心率(HR)、左室收缩压(LVSP)、左室舒张末压(LVEDP)、左室内压最大上升速率(+dp/dtmax)和左室内压最大下降速率(-dp/dtmax)5项血流动力学参数为指标,观察短暂延迟性酸处理对老龄大鼠心肌缺血再灌注后收缩和舒张能力的影响。结果:与C组比较,再灌注期间I/R组、IPO组、H+组、IPO+OH-组和OH-组的LVEDP升高,HR、LVSP、±dp/dtmax降低(P<0.05);与I/R组比较,IPO组和H+组LVEDP降低,HR、LVSP、±dp/dtmax升高(P<0.05)。结论:短暂延迟性酸处理能模拟缺血后处理对离体心脏血流动力学的保护作用,且这种保护作用对老龄大鼠同样有效。

Objective：To observe the effects of prolonged transient acidosis on cardiac hemodynamics in aged rat heart after reperfusion injury. Methods： 60 isolated SD rats hearts（≥ 18 months） perfused by Langendorff were randomly divided into 6 groups （n=10）：（ 1 ）normal control （ C ）group ; （ 2 ） reperfusion injury （ I/R ） group ; （ 3 ）ischemic postconditioning （ IPO ） group ; （4）acidosis （ H ＋ ） group ; （ 5 ）post- conditioning＋alkalotic （IPO＋OH-） group; （6）alkalotic （OH-） group. The direct effects of prolonged transient acidosis on myocardiac contractility were observed by a langendorff apparatus through the hemodynamics parameters including heart rate （HR）, left ventricular systolic pressure （LVSP）, left ventricular end-diastolic pressure （LVEDP）, and ± dp/dtmax. Results：The LVEDP were increased and HR, LVSP, ± dp/dtmax were decreased in I/R group, IPO group, H＋ group, IPO＋OH- group and OH group compared with those in C group （P 〈0.05 ）. The LVEDP were decreased and HR, LVSP, ± dp/dtmax were increased in IPO group and H＋ group compared with those in I/R group（P〈0.05 ）. Conclusion： By comparsion with hemodynamics parameters, prolonged transient acidosis can protect isolated rat heart as well as posteonditioning, and it has the same role on aged rat.