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(α-lipoic 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,α-LA使呼吸周期延长、幅度降低;同时α-LA可使Cd^2+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Cd^2+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Cd^2+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、Cd^2+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。[ |
关键词: 呼吸中枢 延髓面神经后核内侧区 活性氧 呼吸节律 |
DOI:10.3724/SP.J.1008.2007.00254 |
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基金项目:国家自然科学基金(30570670);广东省自然科学基金(5004714). |
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Role of reactive oxygen species in regulation of respiratory rhythm in medial area of nucleus retrofacialis |
HE Guo-jun , WU Zhong-hai , HU De-hui , QIAN Zhi-bin , WANG Xiao-hua |
(1. Department of Physiology, Southern Medical University, Guangzhou 510515, China; 2. No. 476 Clinical Department, General Hospital, PLA Fuzhou Military Area Command, Fuzhou 350002) |
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 (Ⅻ n) and mNRF, were made according to Suzue's method. Simultaneous recording of the Ⅻ n 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-lnsensitive pacemaker neurons. Conclusion: ROS has an excitatory effect on the respiratory rhythm and the cadmium-insensitlve respiratory pacemaker neurons through modulating sodium current.[ |
Key words: respiratory center the medial area of nucleus retrofacialis reactive oxygen species respiratory rhythm |