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Updated: Jul 19, 2026

Measuring Spinal Presynaptic Inhibition in Mice By Dorsal Root Potential Recording In Vivo
Published on: March 29, 2014
Presynaptic inhibition evoked by muscle contraction
Abstract:
1. Contractions of flexor and extensor muscles of the knee and ankle were used to investigate presynaptic inhibition at the spinal level.2. Contractions evoked dorsal root potentials, and increased the excitability of the central terminals of group Ia, Ib and low threshold cutaneous primary afferent fibres.3. The monosynaptic reflexes recorded in response to stimulation of flexor or extensor muscle nerves were depressed, in the presence of strychnine hydrochloride 0.1 mg/kg I.V., by the contractions.4. It is suggested that these presynaptic inhibitory effects are largely due to the activation of Golgi tendon organs by contraction.
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