不同剂量乳化异氟醚预处理对大鼠肾脏缺血再灌注损伤的影响

Effects of different doses of emulsified isoflurane preconditioning on renal ischemia-reperfusion injury

目的 观察不同剂量乳化异氟醚静脉预处理对大鼠肾脏缺血再灌注损伤的影响.方法 选取42只SPF级雄性成年SD大鼠,建立左侧单肾45 min缺血180 min再灌注模型,随机分为6组：假手术组、模型组、乳化异氟醚低、中、高剂量（分别为1、2、4 ml/kg）预处理组及脂肪乳剂预处理组,每组7只.再灌注180 min时测定血清肌酐、尿素氮浓度,光镜及电镜观察肾组织病理学变化,并行肾小管Paller评分.结果 血清肌酐浓度：乳化异氟醚中、高剂量预处理组血清肌酐浓度分别为（61±6）、（63±3）μmol/L,明显低于模型组、乳化异氟醚低剂量及脂肪乳剂预处理组[分别为（98±6）、（96±11）、（94±15） μmol/L] （P＜0.05）,而乳化异氟醚中、高剂量预处理组间比较差异无统计学意义（P＞0.05）;血清尿素氮浓度：乳化异氟醚中、高剂量预处理组血清尿素氮浓度分别为（9.3±2.3）、（9.6±4.2） mmol/L,明显低于模型组、乳化异氟醚低剂量及脂肪乳剂预处理组[分别为（14.5±4.7）、（14.0±3.5）、（13.9 ±4.5）mmol/L] （P ＜0.05）,而乳化异氟醚中、高剂量预处理组间比较差异无统计学意义（P＞0.05）;光镜及电镜观察：与模型组、乳化异氟醚低剂量及脂肪乳剂预处理组比较,乳化异氟醚中、高剂量预处理后肾组织病理损伤程度明显减轻;肾小管Paller评分：乳化异氟醚中、高剂量预处理组肾小管Paller评分分别为（18.5±4.5）、（19.4±4.3）分,明显低于模型组、乳化异氟醚低剂量及脂肪乳剂预处理组[分别为（33.5±5.6）、（32.9±4.8）、（33.2±3.8）分] （P＜0.05）,而乳化异氟醚中、高剂量预处理组间比较差异无统计学意义（P＞0.05）.结论 2、4 ml/kg乳化异氟醚静脉预处理对大鼠肾缺血再灌注损伤具有相似的防护作用.

Objective To observe the effects of different doses of emulsified isoflurane preconditioning on renal ischemia-reperfusion injury of rats.Methods Forty-two male adult SD rats underwent 45 min ischemia followed by 180 min reperfusion of the left kidney after right nephrectomy; these rats were randomly divided into six groups：sham operation group,model group,low,middle and high doses （1,2,4 ml/kg） of emulsified isoflurane preconditioning groups and intralipid preconditioning group,with seven animals in each group.Serum creatinine （Cr） and blood urea nitrogen （BUN） concentrations were measured after 180 min reperfusion.Renal pathological changes were observed by light and electron microscope.Paller scores were calculated according to the tubular injury.Results Serum Cr concentrations：the serum Cr concentrations in middle and high doses of emulsified isoflurane preconditioning groups were significantly decreased compared with those in model group （98 ± 6） μmol/L,low dose of emulsified isoflurane preconditioning group （96 ± 11） μmol/L and intralipid preconditioning group （94 ± 15） μmol/L （P 〈 0.05）.There was no significant difference of serum Cr concentration between the middle and high doses of emulsified isoflurane preconditioning groups （P 〉 0.05）.Serum BUN concentrations：the serum BUN concentrations in middle and high doses of emulsified isoflurane preconditioning groups were markedly reduced compared with those in model group （14.5 ± 4.7） mmol/L,low dose of emulsified isoflurane preconditioning group （14.0 ± 3.5） mmol/L and intralipid preconditioning group （13.9 ± 4.5） mmol/L （P 〈 0.05）.No significant difference was observed on serum BUN concentration between the middle and high doses of emulsified isoflurane preconditioning groups （P 〉 0.05）.Compared with model group,in low dose of emulsified isoflurane and intralipid preconditioning group,the injury of kidney tissues was significantly alleviated after middle and high doses of emulsified isoflurane preconditioning.The Paller＆#39;s scores for acute renal tubular injury in middle and high doses of emulsified isoflurane preconditioning groups were markedly decreased compared with model group （33.5 ± 5.6） scores,low dose of emulsified isoflurane preconditioning group （32.9 ± 4.8） scores and intralipid preconditioning group （33.2 ± 3.8） scores （P 〈 0.05）.No significant differences were observed regarding Paller＆#39;s scores between the middle and high doses of emulsified isoflurane preconditioning groups （P 〉 0.05）.Conclusion Preconditioning with 2 or 4 ml/kg emulsified isoflurane can provide good protection against renal ischemia-reperfusion injury in rats.