Mammalian Locomotor Laboratory, Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
Nat Neurosci. 2010 Feb;13(2):246-52. doi: 10.1038/nn.2482. Epub 2010 Jan 17.
Central pattern generators (CPGs) are spinal neuronal networks required for locomotion. Glutamatergic neurons have been implicated as being important for intrinsic rhythm generation in the CPG and for the command signal for initiating locomotion, although this has not been demonstrated directly. We used a newly generated vesicular glutamate transporter 2-channelrhodopsin2-yellow fluorescent protein (Vglut2-ChR2-YFP) mouse to directly examine the functional role of glutamatergic neurons in rhythm generation and initiation of locomotion. This mouse line expressed ChR2-YFP in the spinal cord and hindbrain. ChR2-YFP was reliably expressed in Vglut2-positive cells and YFP-expressing cells could be activated by light. Photo-stimulation of either the lumbar spinal cord or the caudal hindbrain was sufficient to both initiate and maintain locomotor-like activity. Our results indicate that glutamatergic neurons in the spinal cord are critical for initiating or maintaining the rhythm and that activation of hindbrain areas containing the locomotor command regions is sufficient to directly activate the spinal locomotor network.
中枢模式发生器（CPG）是运动所必需的脊髓神经元网络。谷氨酸能神经元被认为对 CPG 的固有节律产生和启动运动的命令信号很重要，尽管这尚未得到直接证明。我们使用新生成的囊泡谷氨酸转运体 2-通道视紫红质 2-黄色荧光蛋白（Vglut2-ChR2-YFP）小鼠直接研究谷氨酸能神经元在节律产生和运动启动中的功能作用。这条小鼠品系在脊髓和后脑表达 ChR2-YFP。ChR2-YFP 在 Vglut2 阳性细胞中可靠表达，并且 YFP 表达细胞可以被光激活。对腰脊髓或尾侧后脑进行光刺激足以启动和维持类似运动的活动。我们的结果表明，脊髓中的谷氨酸能神经元对于启动或维持节律至关重要，并且激活包含运动命令区域的后脑区域足以直接激活脊髓运动网络。
