不同浓度七氟醚麻醉对新生大鼠远期学习记忆能力的影响

Effects of different concentrations of sevoflurane anesthesia on long-term learning and memory abilities in neonatal rats

目的评价不同浓度七氟醚麻醉对新生大鼠远期学习记忆能力的影响。方法新生SD大鼠27只，雌雄不拘，7日龄，体重12-20g，采用随机数字表法，将其分为3组（n=9）：对照组（C组）、2％七氟醚组（S1组）和3％七氟醚组（S2组），分别吸入空气、2％，七氟醚和3％七氟醚4h。新生大鼠饲养至35日龄行旷场实验，36日龄行Morris水迷宫实验，42日龄进行连续被动回避实验测定大鼠学习记忆能力。结果旷场实验：各组运动时间、运动速度和中央区时间的差异均无统计学意义（P〉0．05）。Morris水迷宫实验：与C组比较，S2组第2～5天、S1组第2～3天寻找平台潜伏期延长，S2组和S2组探索期平台象限滞留时间百分比降低（P〈0．05或0．01）；S2组第3～4天寻找平台潜伏期长于S1，组（P〈0．05）；连续被动回避实验：与C组比较，S1组和S2组训练后24h时潜伏期缩短（P〈0．05）；S2组训练后24h时潜伏期短于S1组（P〈0．05）。结论七氟醚麻醉可呈浓度依赖性地降低新生大鼠远期学习记忆能力。

Objective To evaluate the effects of different concentrations of sevoflurane anesthesia on long- term learning and memory abilities in neonatal rats. Methods Twenty-seven neonatal Sprague-Dawley rats of both sexes, aged 7 days, weighing 12-20 g, were randomly assigned into 3 groups （ n = 9 each） ： control group （C group）, 2% sevoflurane group （S1 group） and 3% sevoflurane group （S2 group）. Groups C, S1 and S2 inhaled air, 2% sevoflurane and 3 % sevofluran for 4 h, respectively. The neonatal rats were reared to 35 days old and underwent open field test, to 36 days old and underwent Morris water maze test, and to 42 days old and underwent continuous multiple-trail inhibition avoidance training. Results Open field test： There was no significant difference in the movement time, movement speed and the time the animals spent in the central square among the 3 groups （ P 〉 0.05）. Morris water maze test： Compared with C group, the looking for platform latency on 2nd-5th days in S2 group and on 2nd-3rd days in S1 group was significantly prolonged, and the percentage of time of staying at the platform quadrant was decreased in Sj and S2 groups （P 〈 0.05 or 0.01 ）. The looking for platform latency on 3rd- 4th days in S2 group was significantly longer than that in group S1 （P 〈 0.05）. Continuous multiple-trail inhibition avoidance training： The latency detected at 24 h after training was significantly shorter in S1 and S2 groups than in group C （ P 〈 0.05）, and in group S2 than in S1 group （ P 〈 0.05） . Conclusion Sevoflurane anesthesia decreas- es the long-term learning and memory function in neonatal rats in a concentration-dependent manner.