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目的:探讨布美他尼对多次七氟烷麻醉后新生大鼠NKCC1、KCC2 mRNA表达变化及成年后焦虑状态的影响。方法:81只新生5 d雄性SD大鼠，随机分为3组(每组n n＝27)。对照组(C组)：正常笼内喂养，不接受麻醉；多次七氟烷麻醉组(MS组)：出生后第5天，第7天，第9天分别接受每天七氟烷麻醉2 h；布美他尼＋七氟烷组(B组)：每次麻醉前30 min接受腹腔注射1.82 mg/kg布美他尼。其中，C组和MS组动物在麻醉前30 min接受皮下注射同等剂量的二甲基亚砜皮下注射，以排除溶媒引起的影响。麻醉苏醒观察30 min后，继续笼内正常母乳喂养。第9天麻醉结束即刻每组取6只动物，动脉血气针左心室穿刺取血进行血气分析；麻醉苏醒后30 min，每组取6只动物断头处死后留取脑组织下丘脑部分，利用RT-PCR技术检测IL-6 mRNA、NKCC1 mRNA和KCC2 mRNA的表达。每组其余15只大鼠继续笼内饲养至60 d进行高架十字迷宫(elevated plus maze，EPM)检测。n 结果:与C组比较，MS组下丘脑IL-6 mRNA和NKCC1 mRNA表达上调[IL-6：(1.000±0.207)，(1.782±0.231)；n t＝6.899，n P<0.01；NKCC1：(1.000±0.255)，(1.639±0.290)；n t＝3.518，n P<0.01]、KCC2 mRNA表达下调[(1.000±0.140)，(0.733±0.115)；n t＝3.017，n P<0.001]、NKCC1/KCC2 mRNA比值增高[(1.000±0.276)，(2.054±0.521)；n t＝5.078，n P<0.001]，差异有统计学意义。与MS组比较，B组下丘脑IL-6 mRNA和NKCC1mRNA表达下调[IL-6：(1.147±0.140)；n t＝5.635，n P<0.01；NKCC1：(1.038±0.385)；n t＝3.310，n P＝0.01]、KCC2 mRNA表达上调[(0.988±0.194)；n t＝2.880，n P<0.05]、NKCC1/KCC2 mRNA比值降低[(1.027±0.200);n t＝4.950，n P<0.001]，差异有统计学意义。EPM行为学实验显示，与C组比较，MS组大鼠开放臂停留时间明显缩短[(18.4±10.1)s，(4.3±3.1)s；n P<0.01]；与MS组比较，B组开放臂停留时间明显延长[(16.6±7.6)s，n P<0.05]。n 结论:布美他尼可以减轻多次七氟烷麻醉后新生大鼠NKCC1表达上调、KCC2表达下调及成年后的焦虑状态。“,”Objective:To investigate the effects of bumetanide on changes of NKCC1 and KCC2 mRNA expression in hypothalamus and anxiety in adulthood induced by multiple sevoflurane exposure in neonatal rats.Methods:Eighty-one healthy male Sprague-Dawley rats, at postnatal 5 days (P5), were randomly divided into 3 groups (n n=27 in each group): control group (group C), multiple sevoflurane group (group MS) and bumetanide group (group B). The rats were commonly reared in the cage and received no anesthesia in group C. Animals were exposed to 2.1% sevoflurane for 2 h on P5, P7, P9 in group MS and group B. In group B, animals received intraperitoneal injection of 1.82 mg/kg bumetanide(Nan + -Kn + -2Cln - cotransporter 1 blocker, NKCC1 blocker)at 30 min before every anesthesia.The animals in group C and group MS received the same dose of dimethyl sulfoxide subcutaneously at the same time as group B. The rats were observed for 30 minutes after recovery from anesthesia, and then breastfed normally.On the 9th day after birth, six rats were taken from each group immediately at the end of anesthesia and the blood was collected by left ventricular puncture for blood gas analysis.At 30 min after anesthesia, 6 animals in each group were decapitated and the hypothalamus part of brain tissue was collected.Then the expression level of IL-6 mRNA, NKCC1 mRNA and KCC2 mRNA were detected by RT-PCR.The other rats in each group were raised to 60 days for the elevated plus maze (EPM) test.n Results:Compared with group C, the expression of IL-6 mRNA and NKCC1 mRNA in hypothalamus of MS group was up-regulated (IL-6: (1.000±0.207) n vs (1.782±0.231); n t=6.899, n P<0.01; NKCC1: (1.000±0.255)n vs (1.639±0.290); n t=3.518, n P<0.01), the KCC2 mRNA expression was down-regulated ((1.000±0.140)n vs (0.733±0.115); n t=3.017, n P<0.001) and the NKCC1/KCC2 mRNA ratio increased ((1.000±0.276)n vs (2.054±0.521); n t=5.078, n P<0.001) and the differences were statistically significant.Compared with MS group, the expression of IL-6 mRNA and NKCC1 mRNA in hypothalamus of group B was down-regulated (IL-6: (1.147±0.140);n t=5.635, n P<0.01; NKCC1: (1.038±0.385);n t=3.310, n P=0.01), KCC2 mRNA expression was up-regulated((0.988±0.194); n t=2.880, n P<0.05), NKCC1 / KCC2 mRNA ratio was decreased((1.027±0.200);n t=4.950, n P<0.001), and the differences were statistically significant.EPM behavioral test showed that compared with group C, the open arm residence time in MS group was significantly shorter than that in group C ((18.4±10.1)sn vs (4.3±3.1)s; n P<0.01); compared with group MS, the open arm residence time in group B was significantly prolonged((16.6±7.6)s,n P<0.05).n Conclusion:Bumetanide can reduce the up-regulation of NKCC1 level and the down-regulation of KCC2 level in neonatal rats after sevoflurane anesthesia, and alleviate the anxiety state of adult rats.