细胞膜电压振荡对脊髓中间神经元节律性放电的调控作用  

Regulation of membrane voltage oscillation on rhythmic firing of spinal interneurons

作　　者：陈玥如 戴跃 CHEN Yueru;DAI Yue(School of Communication and Electronic Engineering,East China Normal University,Shanghai 200241,China)

机构地区：[1]华东师范大学通信与电子工程学院,上海200241

出　　处：《中国医学物理学杂志》2024年第5期610-615,共6页Chinese Journal of Medical Physics

基　　金：国家自然科学基金(32171129)。

摘　　要：为了探究细胞膜振荡状态下离子通道对脊髓中间神经元节律信号的影响,建立了两个猫脊髓中间神经元模型,它们通过交互式抑制的方式相互连接,当受到兴奋刺激时模型能够产生节律性放电。运用该模型,研究了突触输入下白噪音(WN组)、离子通道插入振荡因子(CF组)、以及白噪音与振荡因子同时作用(WN+CF组)3种条件下,神经元模型的兴奋性与运动节律的变化规律,定量化描述中间神经元节律性放电的电压阈值、步进占空比以及瞬时放电频率变化的规律。仿真结果表明,(1)WN组、CF组、WN+CF组电压阈值分别为-46.98、-46.48、-47.00 mV;与控制组相比,WN组和WN+CF组的电压阈值分别降低了0.47和0.49 mV,CF组提高了0.03 mV;(2)WN组、CF组和WN+CF组屈肌和伸肌的瞬时放电频率分别为41.01和41.28 Hz、27.45和27.43 Hz、40.20和40.17 Hz;与控制组相比,分别提高了15.20和15.25 Hz、1.64和1.40Hz、14.39和14.14 Hz;(3)WN组、CF组和WN+CF组步进频率分别为0.72、0.68和0.68 Hz;与控制组相比,WN组增加了0.01 Hz,CF组和WN+CF组分别降低了0.03和0.03 Hz;(4)WN组、CF组和WN+CF组步进占空比分别为49.41%、45.02%、50.18%;与控制组相比,WN组和WN+CF组的步进占空比分别增加了4.27%和5.04%,CF组则减少了0.12%。这些结果显示了膜振荡状态下离子通道对神经元兴奋性以及运动节律的调控作用,为后续的生理实验提供了预测和参考。A model involving two cat spinal interneurons is established to investigate the effects of ion channels on the rhythmic generation in spinal interneurons during the membrane voltage oscillation.In the model,the interneurons are connected with each other through reciprocal inhibition,and can produce rhythmic firing when stimulated by excitation.The established model is used to study the changes in the excitability and rhythmicity of the neurons under 3 conditions,including synapse input with white noise(WN group),channel flicker added to ion channels(CF group),and white noise plus channel flicker(WN+CF group),and to quantify the voltage threshold of interneuron rhythmic firing,step duty cycle,and instantaneous firing frequency.The simulation results show that(1)the voltage thresholds are-46.98,-46.48 and-47.00 mV in WN,CF and WN+CF groups,which are 0.47 mV lower,0.03 mV higher and 0.49 mV lower as compared with control group.(2)The instantaneous firing frequencies of extensor in WN,CF and WN+CF groups are 41.28,27.43 and 40.17 Hz,respectively,which are 15.25,1.40 and 14.14 Hz higher than control group;while the instantaneous firing frequencies of flexor are 41.01,27.45,40.20 Hz,which are 15.20,1.64 and 14.39 Hz higher than control group.(3)The frequencies of step period are 0.72,0.68 and 0.68 Hz in WN,CF and WN+CF groups,which are 0.01 Hz higher,0.03 Hz lower and 0.03 Hz lower as compared with control group.(4)The step duty cycles are 49.41%,45.02%and 50.18%in WN,CF and WN+CF groups.Compared with control group,WN group and WN+CF group increased step duty cycles by 4.27%and 5.04%,while CF group decreased it by 0.12%.These results demonstrate the regulations of ion channels on neuronal excitability and locomotor rhythmicity during the membrane oscillation,providing prediction and reference for subsequent physiological experiments.

关 键 词：膜振荡 中间神经元 离子通道 神经元兴奋性 运动节律 

分 类 号：R318[医药卫生—生物医学工程]