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Updated: Aug 16, 2026

Non-invasive Assessment of Changes in Corticomotoneuronal Transmission in Humans
Published on: May 24, 2017
Group Ia non-reciprocal inhibition from wrist extensor to flexor motoneurones in humans
1Unità di Malattie del Sistema Motorio e Scienze del Movimento, Università degli Studi di Siena, Italy.
Abstract:
Interneurones mediating disynaptic inhibition from extensor to flexor carpi radialis muscles were characterized by pharmacological stimulation of Renshaw cells. It is, indeed, known that only Ia interneurones are blocked by recurrent inhibition. Renshaw cell potentiation, induced by intravenous administration of 2 g levo-acetylcarnitine, blocked Ia reciprocal inhibition from triceps to biceps muscles but not disynaptic inhibition from extensor to flexor carpi radialis muscles. It is concluded that the interneurones mediating this latter inhibition are not Ia interneurones. This kind of inhibition could be an example of a Ia non-reciprocal inhibitory pathway.
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