高氧液对兔心肌缺血再灌注损伤pHi的影响

Effect of hyperoxic liquid on gastric intramucosal pH after myocardial ischemic reperfusion injury in rabbits

目的观察兔心肌缺血再灌注时胃黏膜pH值(pHi)的变化,探讨高氧液对心肌缺血再灌注兔pHi的影响。方法20只成年雄性新西兰大白兔随机分成对照组(n=10)及高氧液组(n=10)。高氧液组每天静脉给予10 mL/kg高氧液,20 min内匀速泵完,连续7 d,对照组用同样方法给予生理盐水,最后一次处理结束后,开胸结扎兔冠状动脉左室支30 min,再灌注后1 h、2 h分别记录心电图,左室内收缩压(LVSP)、左室收缩压上升最大速率(+dp/dt max)、心率和pHi值。结果高氧液明显降低心电图S-T段的升高程度并改善血流动力学变化。pHi在缺血再灌注后显著降低,但高氧液组pHi降低幅度在再灌注后1 h、2 h明显小于对照组(P<0.05)。结论在兔缺血再灌注前,静脉输入高氧液可以明显改善胃肠道微循环灌注和组织氧合。

Objective To investigate the changes in gastric intramucosal pH （pHi） and the effect of hyperoxic liquid on intramucosal pH （pHi） after myocardial ischemia-reperfusion injury in rabbits. Methods Twenty healthy male adult rabbits, weighing 2.3 -3.0 kg, were randomly divided into two groups： control group （ n = 10） and hyperoxic liquid group （n = 10）. Hyperoxic liquid group received the routine infusion of hyperoxic liquidle of 10 mL/kg for seven days, while control group received the routine treatment infusion of saline instead of hyperoxic liquid of 10 mL/kg. Seven days later, the myocardial ischemic reperfusion model （I/R） was established, and ECG and homodynamic indexes were monitored simultaneously. Hemodynamic indexes and pHi were measured before myocardial ischemia, 30 min after myocardial ischemia as well as 1 h and 2 h after reperfusion. Results Hyperoxic liquid could lower ST segment and improve hemodynamic indexes, pHi decreased significantly after myocardial ischemia-reperfusion injury in both groups. Compared with that in control group, pHi was significantly higher at 1 h and 2 h after reperfusion in hyperoxic liquid group （P〈0.05）. Conclusion pHi decreases significantly after myocardial ischemia-reperfusion injury in rabbits. Hyperoxic liquid infusion can improve gastrointestinal microcirculatory per fusion.