8%乳化异氟醚后处理对大鼠局灶性脑缺血再灌注损伤的影响

目的 探讨8%乳化异氟醚后处理对大鼠局灶性脑缺血再灌注损伤的影响.方法 健康成年雄性SD大鼠48只,体重260～300 g,随机分为6组(n=8):假手术组(S组)、缺血再灌注组(I/R组)、低、中、高剂量乳化异氟醚后处理组(L-EI组、M-EI组和H-EI组)和脂肪乳组(LE组).除S组外,均采用大脑中动脉阻闭2 h,再灌注24 h的方法建立局灶性脑缺血再灌注模型.L-EI组、M-EI组和H-EI组分别于再灌注即刻腹腔注射8%乳化异氟醚3.5、7.0、10.5 ml/kg,LE组给予30%脂肪乳10.5 ml/kg,S组与I/R组不给药.再灌注24 h时行神经功能缺陷评分(NDS),取脑组织测定脑梗死体积.结果 与S组比较,其余各组NDS评分升高,脑梗死体积增大(P＜0.01);与I/R组比较,M-EI组和H-EI组NDS评分降低,脑梗死体积减小(P＜0.01),L-EI组和LE组上述指标差异无统计学意义(P＞0.05);与M-EI组比较,H-EI组NDS评分降低,脑梗死体积减小(P＜0.05).结论 8%乳化异氟醚后处理可减轻大鼠局灶性脑缺血再灌注损伤,且与剂量有关.

Effect of 8% emulsified isoflurane postconditioning on focal cerebral ischemia-reperfusion injury in rats

Objective To investigate the effect of postconditioning with 8 % emulsified isoflurane (EI) on focal cerebral ischemia-reperfusion (I/R) injury in rats. Methods Forty-eight male SD rats weighing 260-300 g were randomly divided into 6 groups ( n = 8 each): group Ⅰ sham operation (group S); group Ⅱ I/R; group Ⅲ,Ⅳ, Ⅴ 3 different doses of EI (group L-EI, M-EI, H-.EI) and group Ⅵ lipid emulsion (group LE). Right middle cerebral artery occlusion (MCAO) was induced by inserting a nylon thread 0.24 mm in diameter into right internal carotid artery. The thread was threaded cranially until resistance was met. MCAO was maintained for 2 h followed by 24 h reperfusion in group Ⅱ-Ⅵ. In group Ⅲ-Ⅴ EI 3.5, 7.0 and 10.5 ml/kg were injected intraperitoneally (IP) immediately before reperfusion respectively. In group LE 30% lipid emulsion 10.5 ml/kg was given instead of EI. The neurologic deficit was assessed and scored (0 = normal, 4 = unable to move and unconscious). The animals were then killed and infarct size was measured. Results IP 8% emulsified isoflurane 7.0 and 10.5 ml/kg injected before reperfusion significantly reduced neurologic deficit scores and infarct size in group M-EI and H-EI as compared with group I/R. Conclusion Postconditioning with 8% emulsified isoflurane can protect the brain against focal cerebral I/R injury.