微透析-电化学法检测缺血再灌注损伤对兔肾皮质乳酸代谢的影响

The impact of warm ischemia/reperfusion injury on the lactate metabolism of renal cortical in rabbit measured by in vivo microdialysis coupled with on-line electrochemical detection

目的:采用微透析-电化学方法研究缺血再灌注损伤状况下兔肾皮质乳酸浓度变化的规律。方法:普通级大耳白兔16只,其中实验组10只,戊巴比妥麻醉后,游离出左肾,将微透析探针置入肾皮质内,正常血流灌注状态下平衡60min,再用动脉夹阻断肾动静脉60min,然后开放动静脉60min。应用电化学方法实时在线监测肾透析液中乳酸含量的变化。假手术组6只,同样留置微透析针取样,连续测定乳酸浓度各60min,但是对照组仅游离肾动静脉而不结扎血管。比较正常灌注期、缺血期和再灌注期三种状态下乳酸浓度的变化。结果:兔肾皮质正常状态下透析液乳酸浓度为(1.35±0.33)mmol,缺血期乳酸平均浓度为(3.33±0.35)mmol,缺血期较自身正常灌注期平均升高241.8%。再灌注期肾皮质透析液乳酸浓度平均为(1.86±0.46)mmol,再灌注期内比正常灌注期乳酸浓度平均升高131.4%。实验组内正常灌注期与缺血期肾皮质乳酸浓度差异有统计学意义(P<0.001),与再灌注期乳酸浓度比较差异无统计学意义(P>0.05)。两组正常灌注期和再灌注期组间差异无统计学意义(P>0.05);缺血期乳酸浓度组间差异有统计学意义(P<0.05)。结论:应用微透析-电化学法测定乳酸水平可以良好地实时反映肾皮质缺血状态;热缺血60min内,再灌注后肾皮质乳酸浓度可以下降接近正常水平。

Objective：To investigate the impact of warm ischemia reperfusion injury on the lactate metabolism of renal cortical in rabbit using the methods of in vivo microdialysis coupled with on-line electrochemical detection. Methods： Two groups of rabbits were underwent kidney operation. The left kidney was dissociated and a microdialysis probe was inserted into the renal cortex under anesthesia by intravenous injection of barbitone. Ischemia was achieved by clamping the renal pedicle for 60 minutes followed by perfusion for another 60 minutes in 10 rabbits. The shamed procedure was performed at the same time interval in 6 rabbits as the control group without clamping the renal pedicle. Microdialysis samples Were collected before, during and after ischemia and lactate in the microdialysates were on-line measured with the electrochemical method. Results.. The renal cortical interstitial concentrations of lactate in the microdialysates before, during and after renal warm ischemia were （1.35±0.33） mmol, （3.33±0.35） mmol and （1.86±0.46） mmol, respectively. The concentration of lactate was increased rapidly by 241.8% following ischemia in relative to the basal level （P〈0. 05）. The level of lactate was decreased quickly following reperfusion without a difference （P〉0.05） compared with the basal level and without a difference between groups. Conclusions： The degree of ischemia in renal context can be reflected in real-time by the change of lactate concentration measured by in vivo microdialysis coupled with on-line electrochemical method. The level of lactate could be decreased to nearly the basal level after reperfusion for 60 minutes.