七氟醚对老年大鼠认知功能影响  

Effect of sevoflurane on cognitive function in old rats after cerebral blood flow change

作　　者：陈揭晓[1] 刘毓和[2] 吴新民[2] 梁敏[1] 欧阳碧山[1] 

机构地区：[1]海南省人民医院麻醉科,海口570311 [2]北京大学第一医院麻醉研究室

出　　处：《中国公共卫生》2009年第6期712-714,共3页Chinese Journal of Public Health

基　　金：海南省自然科学基金(805103)

摘　　要：目的探讨吸入麻醉药影响老年大鼠认知功能的可能作用机制。方法老年Wistar大鼠随机分为4组,分别吸入0%(Ⅰ)、2%(Ⅱ)、3%(Ⅲ)七氟醚及左侧颈总动脉结扎+2%七氟醚(Ⅳ),同时分别吸入2L/min的O2+6L/minN2混合气体(5d×100min/d);第4组于吸入混合气体前1周结扎左侧颈总动脉。用Morris水迷宫测试大鼠的认知功能(5d×4次/d);用逆转录-聚合酶链反应法测定海马脑区N-甲基-D-天冬氨酸(NMDA)及其受体(NR)亚单位NR1和NR2B mRNA表达。结果大鼠的平均潜伏期由第1d的88s逐日缩短为第5d的36s,平均游泳距离由851cm缩短为485cm;第1d与第5d比较,前3组游泳距离明显缩短,差异有统计学意义(P<0.01);3%七氟醚组1d潜伏期明显长于Ⅰ组(P<0.05),Ⅳ组比Ⅰ组相应各天潜伏期均延长(P<0.05或P<0.01)。与Ⅰ组相比,Ⅲ组和Ⅳ组平台象限时间均明显缩短。与Ⅰ组比较,Ⅲ组NR mRNA的表达明显增加(P<0.05),Ⅳ组NR2B亚单位mRNA表达则明显增加(P<0.01)。结论七氟醚对老年大鼠术后认知功能呈剂量依赖性抑制作用;脑血流不足影响七氟醚对老年大鼠的认知功能,七氟醚对NMDA受体功能呈部分抑制作用,较低浓度时这种作用并不明显。Objective To investigate the effect of sevoflurane on spatitial cognitive function and the mRNA expressions of N-methyl-D-aspartate （NMDA） receptor and the subunits of NR1 and NR2B in the hippocampus of elderly rats during the cerebral blood flow changes. Methods Thirty Wistar rats were randomly divided into 4 groups：control group （ Ⅰ ,n = 8 ） ,2 % sevoflurane group （ Ⅱ , n = 8 ） ,3 % sevoflurance group （ Ⅲ, n = 8 ） and sevoflurane-isehemia-group （ Ⅳ, n = 6 ）. All rats received 0% ,2 %, 3 % sevoflurane and 02 in a flow rate of 2 L-min- 1 and N2 （6 L-rain- 1 ）, 100 rain every day for 5 days ,respectively. In group IV ,left common cartid artery was ligated before a week of the mixed gas exposure. The cognitive function was tested 4 times a day for 5 consecutive days using Morris water maze. The animals were killed after the Morris water maze test performance. NR, NR1 and NR2B mRNA expressions in the hippocampus were determined using reverse transcriptase-polymerase chain reaction （RT-PCR）. Results The mean of latency period in Ⅰ -Ⅳ groups graduatly short- erned from 88s to 36s on day 1-5 ,and the swimming distance shortened from 851cm to 485cm. The swimming distance was significantly shorter on the 5th day than on the I st day in group Ⅰ, Ⅱ and Ⅲ[ （ P 〈 0. 01 ）. The latency period on the I st day of group Ⅲ and on 1-5th day of group Ⅳ were significantly longer than in control group. The quadrant of hidden-platform of group Ⅲ and Ⅳ were obviously shorter than that of group Ⅰ. The NR mRNA expression in group Ⅲ and NR2B mRNA ex- pression in group IV were markedly higher than group Ⅰ. Conclusion Sevoflurane inhibits cognitive function of elderly rats in dose-dependent manner. Cerebral blood flow deficits influences the effect of sevoflurane on cognitive function in old rats. Sevoflurane at high concentration may inhibit the capacity of NMDA receptor.

关 键 词：七氟醚 脑血流 认知障碍 N-甲基-D-天冬氨酸受体 

分 类 号：R996[医药卫生—毒理学]