异氟醚和安氟醚对大鼠海马神经元自发放电活动的影响

目的　研究吸入麻醉剂安氟醚和异氟醚对大鼠海马神经元自发放电活动的影响。方法　将新生SD大鼠迅速断头取全脑 ,置于通入 1.3 6g·L- 1(95% )O2 和 0 .0 98g·L- 1(5% )CO2 混合气体的 4℃人工脑脊液 (ACSF)中 ,再用振动切片机切制成 3 0 0～ 40 0 μm含海马的脑薄片 ,然后用全细胞膜片钳记录技术 ,分别观察不同浓度的安氟醚和异氟醚对海马神经元自发放电频率的影响。结果　安氟醚和异氟醚都能浓度依赖性地抑制海马CA1区神经元放电频率。安氟醚 (0 .2g·L- 1～ 0 .6g·L- 1)和异氟醚 (0 .12g·L- 1～ 0 .3 6g·L- 1)能使海马CA1区神经元放电频率产生明显的抑制作用 ,冲洗 5min后 ,放电频率可逐渐恢复到给药前水平。结论　安氟醚和异氟醚对大鼠海马CA1区神经元自发放电活动可产生明显可逆性的抑制作用 ,表明海马CA1区是吸入麻醉剂在中枢神经系统中的重要作用部位。

Effects of isoflurane and enflurane on spontaneous neural discharge of hippocampus in rats

Objective To investigate the effects of inhaling isoflurane and enflurane on the spontaneous neural discharge of the neurones in rat hippocampus. Methods Whole cell patchclamp recording te chnique was used to observe the effects of isoflurane and enflurane on the spont aneous discharge rate of the neurons in the hippocampus on the brain slice of ne w-born SD rats. After decapitation, the whole brain of the rat was removed and put into artificial cerebrospinal fluid (ACSF) saturated with 1.36 g·L -1 O 2 and 0.098 g·L -1 CO 2 mixed gas at 4 ℃ . Brain was cut into 300～400 μ m thick slices containing the hippocampus. Whole cell patchc lamp recording technique was used to observe the effects of isoflurane with dif ferent concentrations on the spontaneous discharge rate of neurons in the hippoc ampus on the brain slices. Results Isoflurane and enfluran e could significantly inhibit the spontaneous neural discharge of neurons in the hippocampus in a dose-dependant manner. The effects of spontaneous neural disc harge of hippocampus inhibited by isoflurane (0.12 g·L -1 ～0.36 g·L -1 ) and enflurane (0.2 g·L -1 ～0.6 g·L -1 ) could be recove red following washing off with ACSF for 5 min. Conclusion T he spontaneous discharge rate of neurons in the hippocampus can be reversibly in hibited by isoflurane and enflurane. Hippocampus may be an important action site of anesthetics isoflurane and enflurane in the central nervous system.