Schieppati M, Gritti I, Romano C
Institute of Human Physiology II, University of Milano, Italy.
Acta Physiol Scand. 1991 Sep;143(1):27-32. doi: 10.1111/j.1748-1716.1991.tb09198.x.
A long-latency, long-lasting increase in the recurrent inhibitory effect on the soleus monosynaptic (Hoffmann, H) reflex was induced after intravenous administration of L-acetylcarnitine, a substance known to process central cholinergic activity. This effect was paralleled by disappearance of the H reflex inhibition (functionally disinhibition) induced by stimulation of Ia afferent fibres from the tibialis anterior (reciprocal inhibition) and gastrocnemius medialis muscle. Magnitude and time course of the L-acetylcarnitine-induced effects were significantly correlated. The data suggest that (1) the L-acetylcarnitine depression of the reciprocal inhibition is mediated by excitation of Renshaw cells impinging on Ia interneurones (INs), and (2) the inhibitory effect of GM Ia afferents onto Sol is mediated by INs subjected to Renshaw inhibition. The results point to the similarity in the wiring of the 'output stage' circuit between cat and humans, and provide a method for testing this network in man.
静脉注射L-乙酰肉碱（一种已知可调节中枢胆碱能活性的物质）后，对比目鱼肌单突触（霍夫曼，H）反射的反复抑制作用出现了长时间延迟且持久的增强。这种效应伴随着由刺激来自胫骨前肌（交互抑制）和内侧腓肠肌的Ia传入纤维所诱导的H反射抑制（功能性去抑制）的消失。L-乙酰肉碱诱导效应的大小和时间进程显著相关。数据表明：（1）交互抑制的L-乙酰肉碱抑制作用是由支配Ia中间神经元（INs）的闰绍细胞兴奋介导的；（2）GM Ia传入纤维对Sol的抑制作用是由受闰绍抑制的INs介导的。结果表明猫和人类“输出阶段”电路的布线相似，并提供了一种在人体中测试该网络的方法。
