ACTIVITIES OF IDENTIFIED INTERNEURONS, MOTO-NEURONS, AND MUSCLE-FIBERS DURING FICTIVE SWIMMING IN THE LAMPREY AND EFFECTS OF RETICULOSPINAL AND DORSAL CELL STIMULATION
ACTIVITIES OF IDENTIFIED INTERNEURONS, MOTO-NEURONS, AND MUSCLE-FIBERS DURING FICTIVE SWIMMING IN THE LAMPREY AND EFFECTS OF RETICULOSPINAL AND DORSAL CELL STIMULATION
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DOI：
10.1152/jn.1982.47.5.948
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发表时间：
1982-01-01
影响因子：
2.5
通讯作者：
COHEN, AH
中科院分区：
文献类型：
--
作者：
BUCHANAN, JT;COHEN, AH
应用D-谷氨酸的七鳃鳗离体脊髓产生阶段性活动的腹根，这是类似的完整的游泳动物的肌肉。离体脊髓可以作为一个模型来解释脊椎动物运动节律的产生。几乎所有的慢肌纤维在游泳活动中表现出兴奋性连接电位（EJP）。EJP/cycle的数目随着前根（VR）爆发强度的增加而增加。很少有抽搐纤维是活跃的，这些触发动作电位只有在高强度的VR爆发。如Russell和Wallen所发现的，肌节运动神经元在虚拟游泳期间具有振荡膜电位，其平均在VR爆发（Φ）的中间达到峰值去极化。= 0.21 .+-. 0.05; = 0被定义为VR爆发的开始，并且循环的持续时间被设置为等于1）。外侧中间神经元具有与肌节运动神经元同步的振荡膜电位（峰值去极化φ）。= 0.21 .+-. 0.10）。具有向对侧和尾侧突出的轴突的中间神经元（CC中间神经元）具有振荡膜电位，其在周期中显著更早达到峰值（峰值去极化Φ）。= 0.06 .+-. 0.12）。在虚构的游泳过程中，Mueller细胞的重复细胞内刺激通常引起同侧VR的爆发强度增加和对侧VR的爆发强度降低。在游泳活动中，外侧中间神经元和CC中间神经元在虚构的游泳过程中是活跃的，可能有助于协调身体的波动，但它们在图案生成中的作用尚不清楚。中央模式发生器受到下行和感觉输入的修改。
Application of D-glutamate to the isolated spinal cord of the lamprey produces phasic activity in ventral roots, which is similar to that of the muscles of the intact swimming animal. The isolated spinal cord may be used as a model to explain the generation of locomotor rhythms in a vertebrate. Almost all slow muscle fibers exhibited excitatory junctional potentials (EJP) during swimming activity. The number of EJP/cycle increased with the intensity of ventral root (VR) bursting. Few twitch fibers were active, and these fired action potentials only during high intensities of VR bursts. As was found by Russell and Wallen, myotomal motoneurons had oscillating membrane potentials during fictive swimming which, on the average reached a peak depolarization in the middle of the VR burst (.phi. = 0.21 .+-. 0.05; .phi. = 0 is defined as the onset of the VR burst, and the duration of the cycle is set equal to 1). Lateral interneurons had oscillating membrane potentials in synchrony with those of myotomal motoneurons (peak depolarization .phi. = 0.21 .+-. 0.10). Interneurons with axons projecting contralaterally and caudally (CC interneurons) had oscillating membrane potentials that peaked significantly earlier in the cycle (peak depolarization .phi. = 0.06 .+-. 0.12). Repetitive intracellular stimulation of Mueller cells during fictive swimming generally evoked an increased burst intensity in ipsilateral VR and a decreased burst intensity in contralateral VR. During swimming activity, lateral interneurons and CC interneurons are active during fictive swimming and probably help coordinate the undulations of the body, but their roles in pattern generation are not known. The central pattern generator is subject to modification by descending and sensory inputs.