A method for potentiating Renshaw cell activity in humans.

R Mazzocchio; A Rossi

doi:10.1016/s1385-299x(97)00028-7

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A method for potentiating Renshaw cell activity in humans.

R Mazzocchio·A Rossi

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Abstract

Owing to the introduction of a special electrophysiological method [3] it has been possible to study spinal recurrent inhibition in humans. The method, however, is indirect and, being based on an H reflex technique, can only be tested in motor nuclei from which a large monosynaptic response can be obtained. We have developed a complementary method by which pharmacological stimulation of Renshaw cells is obtained [6]. It exploits the central cholinergic properties of L-acetylcarnitine [18], a substance which most likely acts potentiating the synaptic drive of the motoneurone collaterals [7], known to be the main source of excitation of Renshaw cells [15,20]. The use of L-acetylcarnitine has allowed to establish the validity of the original methodology [6] and to confirm the presence of recurrent inhibition, tested either by the H reflex technique [11-13] or, if not possible, by the PSTH technique and/or rectified averaged EMG analysis [1,4], in many limb motor nuclei. Thus, it can be expected that L-acetylcarnitine may be used as an independent means for identifying changes in motoneuronal activity related or attributed to the influence of Renshaw cells.

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Acetylcarnitine Adult Electric Stimulation Electromyography H-Reflex Humans Interneurons Knee Joint Motor Activity Motor Neurons Muscle, Skeletal Spinal Cord Synapses Wrist Joint Journal Article Research Support, Non-U.S. Gov't

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R Mazzocchio, A Rossi. 1997-12-01. A method for potentiating Renshaw cell activity in humans.. https://doi.org/10.1016/s1385-299x(97)00028-7

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