七氟烷全身麻醉下SD大鼠外侧缰核与前额叶神经功能网络的研究

Neural functional network of the lateral habenula and prefrontal cortex in SD rats under general anesthesia with sevoflurane

Key words:  七氟烷  全身麻醉  多通道记录  脑电图； 大鼠

Key words:  sevoflurane  general anesthesia  multi-electrode recording  electroencephalogram  rat

Abstract:

目的 研究SD大鼠外侧缰核与前额叶在七氟烷麻醉下脑功能网络的动态变化，揭示七氟烷发挥全身麻醉作用的潜在神经机制。 方法 选择8~12周龄的SD大鼠，采用在体多通道电极分别在前额叶及外侧缰核脑区植入电极，采用2%的七氟烷进行诱导与维持，采集外侧缰核及前额叶皮层脑电的实时电信号。分别计算并比较清醒、麻醉以及复苏期的前额叶与外侧缰核脑电功率、相干性以及格兰杰因果关系等指标，探究七氟烷麻醉对外侧缰核及前额叶电生理活动的影响。 结果 相比清醒状态，七氟烷麻醉可以引起前额叶与外侧缰核的delta频段功率显著上升(前额叶: P=0.030 9；外侧缰核: P<0.001)以及高频gamma振荡的下降(前额叶: P=0.682 4；外侧缰核: P<0.000 1)；七氟烷麻醉可以引起显著的delta频段的相干性增加(P<0.001)以及前额叶到外侧缰核的信息流动异常增强(P<0.01)。 结论 外侧缰核与前额叶delta频段功率以及相干性的增加，并伴随前额叶到外侧缰核的信息流动异常增强是导致七氟烷麻醉引起意识丧失的可能机制。

Abstract:

Objective To investigate the dynamic changes in the brain functional network between the lateral habenula and the prefrontal cortex under anesthesia with sevoflurane in rats, and to elucidate the potential neural mechanisms by which sevoflurane exerts its systemic anesthetic effects. Methods Eight to twelve-week-old SD rats were selected. Multi-channel electrodes were implanted separately in the prefrontal cortex and lateral habenula brain regions. Anesthesia was induced and maintained with 2% sevoflurane, and real-time electrical signals were collected from the lateral habenula and prefrontal cortex. The power, coherence, and Granger causality of the prefrontal cortex and lateral habenula electroencephalogram(EEG) were calculated and compared during wakefulness, anesthesia, and recovery periods to explore the effects of sevoflurane on the electrophysiological activity of the lateral habenula and prefrontal cortex. Results Compared to the awake state, sevoflurane anesthesia induced a significant increase in delta-band power in the prefrontal cortex and lateral habenula(prefrontal cortex: P=0.030 9; lateral habenula: P<0.001), as well as a decrease in high-frequency gamma oscillations(prefrontal cortex: P=0.682 4; lateral habenula: P<0.000 1). Sevoflurane anesthesia leaded to a significant increase in coherence in the delta frequency band(P<0.001) and abnormal enhancement of information flow from the prefrontal cortex to the lateral habenula(P<0.01). Conclusion The increase in delta band power and coherence between the lateral habenula and prefrontal cortex, along with the enhanced abnormal information flow from the prefrontal cortex to the lateral habenula, may be potential mechanisms underlying the loss of consciousness induced by sevoflurane anesthesia.