反复吸入七氟烷对老年大鼠认知功能的影响

目的 评价反复吸入七氟烷对老年大鼠认知功能的影响.方法 健康Wistar大鼠24只,月龄18月,体重270-450 g,雌雄各半,随机分为3组(n=8):对照组(C组)、2%七氟烷组(S1组)和3%七氟烷组(S2组).C组不吸入七氟烷;S1和S2组分别吸入2%、3%七氟烷,100 min/d,连续5d.于干预结束后1-6d(T1-6)时进行水迷宫实验,记录T1-5时游泳时间和游泳距离及T6时第4象限探索时间和游泳距离.于最后1次水迷宫实验结束后60 min处死大鼠,取海马组织,采用RT-PCR法测定海马N-甲基肌天冬氨酸受体(NMDAR)、NR1和NR2B mRNA的表达.结果 与C组比较,S1组T1时游泳时间和游泳距离延长.T6时第4象限探索时间缩短,NMDAR mRNA表达上调(P<0.05),NRI和NR2B mRNA的表达差异无统计学意义(P<0.05).结论 反复吸入2%七氟烷不会导致老年大鼠认知功能减退;而反复吸入3%七氟烷可导致一过性认知功能减退.

Effect of repeated inhalation of sevoflurane on cognitive function in aged rats

Objective To investigate the effects of repeated inhalation of sevoflurane on cognitive function in aged rats. Methods Twenty-four Wistar rats of beth sexes aged 18 months weighing 270-450 g were randomly divided into 3 groups(n=8 each):control group(C),2%aevoflurane group(S1)and 3% sevoflurane group (S2).Group C inhaled oxygen(2.5 L/min)and nitrogen(6L/min)only, while group S1 and S2 inhaled 2%and 3%sevonurane in oxygen(2.5 L/min)and nitrogen(6 L/min)100 min/d for 5 d respecfivelv. The Morris watemaze test was performed once a day for 6 consecutive clays after the last inhalation(T1-6).The swimming time and distance at T1-5 and probe time and swimming distance in the fourth quadrant at T6 were recorded. The aninlala were killed within 60 min after the last test and the hippecampus were immediately removed for determination ofthe expression of NMDAR, NRI and NR2B mRNA using RT-PCR.Results The swimming time and disl .ance were significantly longer at T1,and the probe time in the fourth quadrant shorter and expression of NMDAR mRNA hisher at T6 in group s2 than in group C(P<0.05).Conclusion Repeated inhalation of 2% sevoflurane can not induce cognitive disordel-,while 3%sevoflurane Call induce transient cognitive decline in aged rats.