Contreras-Hernández E, Chávez D, Rudomin P
Department of Physiology, Biophysics and Neurosciences, Center of Research and Advanced Studies of the Instituto Politécnico Nacional, México.
El Colegio Nacional, México.
J Physiol. 2015 May 15;593(10):2343-63. doi: 10.1113/jphysiol.2014.288134. Epub 2015 Mar 17.
Previous studies on the correlation between spontaneous cord dorsum potentials recorded in the lumbar spinal segments of anaesthetized cats suggested the operation of a population of dorsal horn neurones that modulates, in a differential manner, transmission along pathways mediating Ib non-reciprocal postsynaptic inhibition and pathways mediating primary afferent depolarization and presynaptic inhibition. In order to gain further insight into the possible neuronal mechanisms that underlie this process, we have measured changes in the correlation between the spontaneous activity of individual dorsal horn neurones and the cord dorsum potentials associated with intermittent activation of these inhibitory pathways. We found that high levels of neuronal synchronization within the dorsal horn are associated with states of incremented activity along the pathways mediating presynaptic inhibition relative to pathways mediating Ib postsynaptic inhibition. It is suggested that ongoing changes in the patterns of functional connectivity within a distributed ensemble of dorsal horn neurones play a relevant role in the state-dependent modulation of impulse transmission along inhibitory pathways, among them those involved in the central control of sensory information. This feature would allow the same neuronal network to be involved in different functional tasks.
先前对麻醉猫腰段脊髓记录的自发脊髓背电位之间相关性的研究表明，一群背角神经元发挥作用，以不同方式调节沿介导Ib非交互性突触后抑制的通路以及介导初级传入去极化和突触前抑制的通路的传递。为了进一步深入了解这一过程背后可能的神经元机制，我们测量了单个背角神经元的自发活动与这些抑制性通路间歇性激活相关的脊髓背电位之间相关性的变化。我们发现，背角内高水平的神经元同步与介导突触前抑制的通路相对于介导Ib突触后抑制的通路活动增加的状态相关。有人提出，背角神经元分布式集合内功能连接模式的持续变化在沿抑制性通路的冲动传递的状态依赖性调节中发挥相关作用，其中包括参与感觉信息中枢控制的那些通路。这一特征将使同一个神经元网络能够参与不同的功能任务。
