Parallel reflex pathways from flexor muscle afferents evoking resetting and flexion enhancement during fictive locomotion and scratch in the cat
Parallel reflex pathways from flexor muscle afferents evoking resetting and flexion enhancement during fictive locomotion and scratch in the cat
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来自屈肌传入的平行反射通路在猫的虚构运动和抓挠过程中引起重置和屈曲增强
DOI：
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
D. McCrea
中科院分区：
文献类型：
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作者：
K. Stecina;J. Quevedo;D. McCrea
在去大脑猫的中脑刺激诱发的虚构运动和虚构抓挠期间，对外周神经中记录的同侧运动神经元活动检查了后肢屈肌神经中肌肉传入的反射作用。在屈曲阶段期间，以足以激活组I和组II传入神经（5倍阈值，T）的强度提供刺激（15-30次电击，200 Hz）。在许多制备中，胫骨前肌（TA）神经刺激终止了持续的屈曲并将运动周期重置为伸展（19/31个实验），而趾长伸肌（EDL）刺激增加并延长了持续的屈肌阶段活动（20/33个制备）。缝匠肌、髂腰肌和腓骨长肌的传入刺激的效果在性质上类似于EDL神经。仅在较高强度刺激（5 T）下观察到复位至伸展，而在I组强度（2 T）刺激下，持续屈肌活动通常增强。屈肌神经刺激的效果是定性相似的虚构的划痕。在一些虚构的运动准备一致观察到反射逆转。在这些情况下，EDL刺激产生复位到伸展和TA刺激延长了正在进行的屈曲阶段。偶尔反射逆转自发发生在几个刺激介绍之一。屈肌传入神经对运动步周期的变化和相反的作用表明存在平行的脊髓反射通路。一个假设的组织反射路径从屈肌传入脊髓图案发生器网络与竞争的行动组I和组II传入的屈肌和伸肌部分，这个中央电路的建议。
Reflex actions of muscle afferents in hindlimb flexor nerves were examined on ipsilateral motoneurone activity recorded in peripheral nerves during midbrain stimulation‐evoked fictive locomotion and during fictive scratch in decerebrate cats. Trains of stimuli (15–30 shocks at 200 Hz) were delivered during the flexion phase at intensities sufficient to activate both group I and II afferents (5 times threshold, T). In many preparations tibialis anterior (TA) nerve stimulation terminated ongoing flexion and reset the locomotor cycle to extension (19/31 experiments) while extensor digitorum longus (EDL) stimulation increased and prolonged the ongoing flexor phase activity (20/33 preparations). The effects of sartorius, iliopsoas and peroneus longus muscle afferent stimulation were qualitatively similar to those of EDL nerve. Resetting to extension was seen only with higher intensity stimulation (5T) while ongoing flexor activity was often enhanced at group I intensity (2T) stimulation. The effects of flexor nerve stimulation were qualitatively similar during fictive scratch. Reflex reversals were consistently observed in some fictive locomotor preparations. In those cases, EDL stimulation produced a resetting to extension and TA stimulation prolonged the ongoing flexion phase. Occasionally reflex reversals occurred spontaneously during only one of several stimulus presentations. The variable and opposite actions of flexor afferents on the locomotor step cycle indicate the existence of parallel spinal reflex pathways. A hypothetical organization of reflex pathways from flexor muscle afferents to the spinal pattern generator networks with competing actions of group I and group II afferents on the flexor and extensor portions of this central circuitry is proposed.
影响因子：
2.5
作者：
Carlson-Kuhta, P;Trank, TV;Smith, JL
通讯作者：
Smith, JL
影响因子：
2.5
作者：
Smith, JL;Carlson-Kuhta, P;Trank, TV
通讯作者：
Trank, TV