【摘要】 目的:探讨活性氧族(reactive oxygen species,ROS)在延髓面神经后核内侧区(the medial area of nucleus retrofacia-lis,mNRF)对呼吸节律调控的作用。方法:仿Suzue方法制作新生大鼠含有舌下神经根及mNRF的离体延髓脑片标本,以吸附电极记录舌下神经根呼吸节律性放电活动(respiratory rhythmic activity,RRA)作为呼吸活动的指标,采用全细胞膜片钳记录模式在mNRF同步记录呼吸神经元。分别观察特丁基氢过氧化物(t-butyl hydroperoxide,tBHP)、α-硫辛酸(-αlipoic acid,α-LA)对mNRF呼吸起步神经元及RRA的影响。结果:tBHP可显著使呼吸周期缩短、幅度增加,-αLA使呼吸周期延长、幅度降低;同时α-LA可使Cd2+非敏感性呼吸起步神经元动作电位周期显著延长,幅度降低,对Cd2+敏感性呼吸起步神经元无显著影响;voltage steps和ramps表明α-LA可抑制Cd2+非敏感性起步神经元的短暂性和持久性的钠电流。结论:ROS对RRA、Cd2+非敏感性起步神经元具有兴奋性作用,是通过调节钠电流而起作用的。更多还原

【Abstract】 Objective:To explore the role of reactive oxygen species（ROS,i.e,H₂O₂ and O₂-） in regulation of respiratory rhythm in the medial area of nucleus retrofacialis（mNRF）.Methods: Medullary slices of neonatal SD rats,including hypoglossal nerve（Ⅻn） and mNRF,were made according to Suzue’s method.Simultaneous recording of the Ⅻn respiratory rhythmic activity（RRA） with suction electrode and the respiratory neuronal discharge were performed with whole cell patch in the mNRF on the brainstem slice in vitro.The effect of t-butyl hydroperoxide（tBHP） and α-lipoic acid（α-LA） on the respiratory pacemaker neurons and respiratory rhythm in the mNRF were observed.Results: tBHP significantly decreased respiratory cycle（RC） and increased respiratory amplitude;α-LA significantly increased RC and decreased its amplitude.Meanwhile,α-LA significantly prolonged the action potential of the respiratory cadmium-insensitive pacemaker neurons and reduced its amplitude,but it had no significant effect on the cadmium-sensitive respiratory pacemaker neurons.Voltage steps and ramps showed that α-LA inhibited both the transient and persistent sodium current of cadmium-insensitive pacemaker neurons.Conclusion: ROS has an excitatory effect on the respiratory rhythm and the cadmium-insensitive respiratory pacemaker neurons through modulating sodium current.更多还原