大鼠移植肾脏细胞凋亡通路与丙泊酚的影响

摘要

背景:肾脏缺血/再灌注损伤是临床常见的病理生理改变,全麻药丙泊酚已证实有一定的抗缺氧损伤的作用,有关细胞凋亡通路方面的作用尚不明确.目的:观察丙泊酚对肾移植大鼠肾脏局部血流动力学的改变以及对内源性线粒体凋亡信号通路中关键蛋白表达的干预,探讨丙泊酚是否具有保护肾脏的作用.设计:随机对照动物实验.单位:首都医科大学附属天坛医院麻醉科,首都医科大学附属友谊医院麻醉科.材料:实验于2005-01/04在北京友谊医院动物实验中心完成.选取成年近交系Lewis雄性大鼠40只,随机数字表法分为假手术组(8只)、单纯肾移植组(供体8只,受体8只)、肾移植+丙泊酚组(供体8只,受体8只).丙泊酚(意大利Astrazeneca公司,产品批号CG414).方法:①大鼠肾脏移植模型制作:单纯肾移植组供体大鼠麻醉后常规取肾,体外修复供体肾脏.受体大鼠以同法麻醉,切除受体的左侧肾脏,行异体原位肾移植术,供体在进行取肾前25 min单次静脉输入乳酸林格液1 mL/kg,受体在开放肾血管前15 min持续输注乳酸林格液2.5 mL/(kg·h).肾移植+丙泊酚组肾移植模型制作同单纯肾移植组,在对应时间点供体大鼠单次注射丙泊酚20 mg/kg,受体大鼠输注丙泊酚1 mg/(kg·min).假手术组不进行肾脏移植,造成左肾缺血,夹闭1 h后松钳使血流再灌注.②用多普勒血流超声仪进行血流动力学观察,置超声探头于检测的血管局部测定供肾在自体和异体血管再通后的肾静脉血流速度.采用蛋白免疫印迹分析法观察内源性线粒体细胞凋亡通路中Bcl-2,Bax,Caspase 3以及细胞色素C的表达.主要观察指标:①各组大鼠血流动力学的变化.②丙泊酚对大鼠移植肾脏细胞凋亡通路蛋白表达的影响.结果:①各组大鼠血流动力学的变化:与假手术组比较,单纯肾移植组、肾移植+丙泊酚组供肾在供体时肾静脉血流速度差异无显著性意义(P＞0.05);单纯肾移植组、肾移植+丙泊酚组供肾在受体时肾静脉血流速度均显著下降[(7.33±0.42),(5.79±0.38),(4.46±0.43)cm/s;P＜0.05].②丙泊酚对大鼠移植肾脏细胞凋亡通路蛋白表达的影响:与假手术组比较,单纯肾移植组抑凋亡蛋白Bcl-2表达降低,而促凋亡蛋白Bax、细胞色素C以及Caspase 3表达增强.与单纯肾移植组比较,肾移植+丙泊酚组肾组织Bcl-2表达增强,同时Bax、细胞色素C以及Caspase 3的表达降低.结论:丙泊酚可降低大鼠移植肾脏的肾静脉血流速度,同时抑制大鼠移植肾脏的冷缺血/再灌注损伤引发的内源性线粒体细胞凋亡信号通路中相关蛋白的表达,可能具有肾保护作用.%BACKGROUND: Renal ischemia/reperfusion injury is a common patho physiological change on clinic. It is proved that propofol has a certain ef fect on anti-hypoxia injury, but its effect on apoptosis pathways is still unclear.OBJECTIVE: To observe the local changes of hemodynamics and expressions of the key protein in endogenetic-mitochondrion signaling apoptosis pathways, and to verify the protective effect of propofol on renal function of rats in during renal transplantation.DESIGN: Randomized controlled animal study. SETTING: Department of Anesthesiology, Tiantan Hospital affiliated to Capital University of Medical Sciences; Department of Anesthesiology,Friendship Hospital affiliated to Capital University of Medical Sciences.MATERIALS: The experiment was carried out at the Animal Experimental Center of Beijing Friendship Hospital from January to April 2005. Fortymale adult Lewis rats from inbred line were divided into three groups according to randomly digital table, including sham operation group (n=8),mere renal transplantation group (8 donators, 8 receptors) and renal transplantation + propofol group (8 donators, 8 receptors). Propofol was provided by Astrazeneca Company, Italian (batch number: CG414).METHODS: ① Establishment of models of renal transplantation: Donator rats in mere renal transplantation group were anesthetized to routinely obtain kidney which was repaired in vitro. Receptor rats were anesthetized with the same way. Left kidney was resected and suffered from xenoma renal transplantation in situ. Twenty-fiveminutes ago, donators were intra venously injected with 1 mL/kg ringer lactate solution, and receptors were successively infused with 2.5 mL/(kg·h) ringer lactate solution at 15 minutes before opening renal vessel. Rats in renal transplantation + propofol group were treated with the same way mentioned above. However, at the same time point, donators were infused with 20 mg/kg propofol and receptors were infused with 1 mg/(kg·min) propofol in renal transplantation+ propofol group. Rats in sham operation group did not suffer from renal transplantation, but induced ischemia of left kidney. Then, blood was reperfused at 1 hour after ischemia. ② Hemodynamics was observed with Doppler blood ultrasound technique, and blood velocity of renal vein was detected with ultrasonic probe which was fixed at local vessels after repenetration of auto- and foreign vessels. Expressions of Bcl-2, Bax, caspase 3 and cytochrome C were detected in endogenetic-mitochondrion signaling apoptosis pathways with the method of Western Blot.MAIN OUTCOME MEASURES: ① Hemodynamic changes; ② effect of propofol on expressions of apoptosis-pathways protein during renal transplantation.RESULTS: ① Hemodynamic changes: Blood velocity of renal vein of donators was not significantly different in mere renal transplantation group and renal transplantation + propofol group from that in sham operation group (P ＞ 0.05); but blood velocity of renal vein of receptors was decreased in all three groups [(7.33±0.42), (5.79±0.38), (4.46±0.43) cm/s; P＜ 0.05]. ② Effect of propofol on expressions of apoptosis-pathways protein during renal transplantation: As compared with those in sham operation group, expression of Bcl-2 protein was decreased in mere renal transplantation group, but expressions of Bax, cytochrome C and caspase 3 were in creased. As compared with those in mere renal transplantation group, expression of Bcl-2 protein was increased in renal transplantation + propofol group, but expressions of Bax, cytochrome C and caspase 3 were decreased.CONCLUSION: Propofol can decrease the blood velocityof renal vein,inhibit the expressions of relative proteins in endogenetic-mitochondrion signaling apoptosis pathways induced by cold ischemia/reperfusion injury,and protect renal function of rats during renal transplantation.