吸入麻醉剂氟烷对大鼠视上核和杏仁中央核神经元自发放电频率的影响

EFFECTS OF THE VOLATILE ANESTHETIC HALOTHANE ON THE SPONTANEOUS DISCHARGE RATE OF NEURONS IN THE SUPRAOPTIC NUCLEUS AND CENTRAL AMYGDALOID NUCLEUS IN THE RAT

为了探讨吸入麻醉剂对中枢神经元作用的机制 ,应用膜片钳全细胞记录技术在新生 SD大鼠脑薄片上观察了吸入麻醉剂氟烷对视上核和杏仁中央核自发放电频率的影响。结果证明 ,0 .75 %、1.5 %和 2 .5 5 %浓度的氟烷对杏仁中央核神经元的自发放电频率可产生不同程度的抑制作用 ,而对视上核神经元的自发放电频率则产生明显的增强效应。给药后用人工脑脊液冲洗 5min后 ,1.5 %浓度的氟烷对神经元的作用可恢复至给药前水平。本研究的结果提示 ,吸入麻醉剂氟烷能明显地改变中枢神经元自发放电频率 ,但对不同部位的神经元 ,氟烷的作用不同 ;视上核和杏仁中央核是麻醉剂对中枢神经系统作用的重要部位。

In order to investigate the mechanism of volatile anesthetic halothane on neurons in the central nervous system (CNS), the whole cell patch clamp recording technique was used to observe the effects of halothane on the spontaneous discharge rate of neurons in the supraoptic nucleus (SO) and central amygdaloid nucleus (Ce) on the brain slice of new born SD rat. After decapitation, the whole brain of the new born SD rat was removed and put into artificial cerebrospinal fluid (ACSF) saturated with 95% O 2 and 5% CO 2 mixed gas at 4℃. Brain was cut into 300～400 μm thick slices in which the SO and Ce were contained. Halothane with different concentrations (0.75%, 1.5% and 2.55%) had dose dependent reversible effects on the spontaneous discharge rate of neurons in the SO and Ce. Halothane increased and reduced the spontaneous discharge rate of neurons in the SO and Ce, respectively. 5 mins after ACSF washing following administration of halothane, the spontaneous discharge rate of the neurons in the SO and Ce recovered to the normal level as that before administration of halothane. The present results indicate that volatile anesthetic halothane might change the spontaneous discharge rate of neurons in the CNS, while in the different nucleus, the halothane has different effects on the neuronal electrical activities. The present results also suggest that SO and Ce are important action sites for general anesthetics in the CNS.