美国哈佛医学院Zhigang He研究小组发现，延髓头端腹内侧的脊髓投射神经元共同调节运动和交感神经张力。这一研究成果于2024年5月10日在线发表在国际学术期刊《细胞》上。
通过光刺激麻醉小鼠的不同脊髓下行投射神经元（SPN）群，研究人员发现刺激延髓头端腹内侧（rVMM）的兴奋性SPN会导致躯体运动和交感神经活动同时增加。相反，光刺激rVMM的抑制性SPN则会降低这两种活动。在解剖学上，这些SPN同时支配交感神经节前神经元和脊髓中与运动相关的区域。纤维光度记录表明，在不同的唤醒状态下，rVMM SPN的活动与不同水平的肌肉和交感神经张力相关。
抑制rVMM兴奋性SPN会降低基础肌肉和交感神经张力，从而影响运动的启动和高速表现。与此相反，在快速眼动（REM）睡眠期间，抑制性群体的沉默可消除肌肉失张力和交感神经活性低下。这些结果共同表明，rVMM SPN是控制躯体运动系统和交感系统张力的脊髓下行投射通路。
据悉，许多行为都需要躯体功能和自律神经功能的协调作用。然而，其潜在的机制仍然难以捉摸。
附：英文原文
Title: Spinal projecting neurons in rostral ventromedial medulla co-regulate motor and sympathetic tone
Author: Zicong Zhang, Junfeng Su, Jing Tang, Leeyup Chung, Jessica C. Page, Carla C. Winter, Yuchu Liu, Evgenii Kegeles, Sara Conti, Yu Zhang, Jason Biundo, Joshua I. Chalif, Charles Y. Hua, Zhiyun Yang, Xue Yao, Yang Yang, Shuqiang Chen, Jan M. Schwab, Kuan Hong Wang, Chinfei Chen, Michael J. Prerau, Zhigang He
Issue&Volume: 2024-05-10
Abstract: Many behaviors require the coordinated actions of somatic and autonomic functions.However, the underlying mechanisms remain elusive. By opto-stimulating different populationsof descending spinal projecting neurons (SPNs) in anesthetized mice, we show thatstimulation of excitatory SPNs in the rostral ventromedial medulla (rVMM) resultedin a simultaneous increase in somatomotor and sympathetic activities. Conversely,opto-stimulation of rVMM inhibitory SPNs decreased both activities. Anatomically,these SPNs innervate both sympathetic preganglionic neurons and motor-related regionsin the spinal cord. Fiber-photometry recording indicated that the activities of rVMMSPNs correlate with different levels of muscle and sympathetic tone during distinctarousal states. Inhibiting rVMM excitatory SPNs reduced basal muscle and sympathetictone, impairing locomotion initiation and high-speed performance. In contrast, silencingthe inhibitory population abolished muscle atonia and sympathetic hypoactivity duringrapid eye movement (REM) sleep. Together, these results identify rVMM SPNs as descendingspinal projecting pathways controlling the tone of both the somatomotor and sympatheticsystems.
DOI: 10.1016/j.cell.2024.04.022
Source: https://www.cell.com/cell/abstract/S0092-8674(24)00447-1