反复吸入七氟烷对幼年大鼠认知功能的影响

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

目的评价反复吸人七氟烷对幼年大鼠认知功能的影响。方法健康雄性SD大鼠108只，25～35日龄，体重90～100g，随机分为6组（n=18），C1组、C2组和C3组每天同一时间吸入纯氧0．5L／min，1h／次，分别吸入1、3、5d；S1组、S2组和S3组每天同一时间吸入2．3％七氟烷及纯氧0．5L／min，1h／次，分别吸1、3、5d。干预结束后7d，各组随机取10只大鼠进行水迷宫实验，记录达标所需训练次数、逃避潜伏期及进入盲端次数；其余8只记录神经电生理强直刺激后群峰电位（PS）振幅，计算长时程增强（LTP）诱发成功率。结果各组大鼠水迷宫实验达标所需训练次数、逃避潜伏期及进入盲端次数差异无统计学意义（P〉0．05）。与C3组比较，S3组LTP诱发成功率降低（P〈0．05）；C1组与S1组比较、C2组与S2组比较差异均无统计学意义（P〉0．05）。结论反复吸入七氟烷虽可抑制幼年大鼠LTP形成，但抑制程度较轻，对认知功能无明显影响。

Objective To investigate the effects of repeated inhalation of sevoflurane on cognitive function in infantile rats. Methods One hundred and eight 25-35 day old infantile SD rats weighing 90-100 g were randomly divided into 6 groups （ n = 18 each） ： group C1 , C2, C3 and group S1 ,S2, S3. Group C1 , C2 and C3 inhaled pure oxygen （0.5 L/min） 1 hid for 1, 3 and 5 d respectively, while group S1 , S2 and S3 inhaled 2.3% sevoflurane in 02 （0.5 L/min） 1 h/d for 1, 3 and 5 d respectively. Seven days after the last inhalation, learning and memory function were assessed using Morris Water Maze （MWM） test in 10 animals in each group; another 8 animals were decapitated under ether anesthesia. Brains were removed and hippocampal slices were prepared and long-term potentiation （LTP） was induced according to the technique described by Lynch. Results There were no significant differences in the number of exercises required for the rats to reach the safe platform, the latency of escaping and the number of times the rats entered the dead end between the corresponding group C and S. The success rats of LTP induction was significantly lower in group S3 than in group C3. There was no significant difference in the success rate of LTP induction between group C1 and S1 and group C2 and S2. Conclusion Although repeated inhalation of sevoflurane can depress the formation of LTP, the degree of depression is too low to influence the cognitive function in infantile rats.