Electrophysiological properties of Ia excitation and recurrent inhibition in cat abdominal motoneurons

• Published in: The journal of physiological sciences Vol. 69; no. 2; pp. 253 - 262
• Main Authors: Niwa, Masatoshi, Muramatsu, Ken, Nakayama, Kiyomi, Sasaki, Sei-Ichi
• Format: Journal Article
• Language: English
• Published: Japan Springer 01.03.2019; BioMed Central; Springer Japan
• Subjects: Abdomen; Abdominal Cavity - physiology; Animals; Axon collaterals; Axons; Axons - physiology; Cats; Dorsal roots; Electric Stimulation - methods; Electrophysiological Phenomena - physiology; Hindlimb - physiology; Interneurons; Latency; Membrane Potentials - physiology; Motor neurons; Motor Neurons - physiology; Motor task performance; Muscle, Skeletal - physiology; Muscles; Original Paper; Renshaw cells; Sensory neurons; Spinal Nerve Roots - physiology; Synapses - physiology; Recurrent IPSP; Spinal cord; Ia-EPSP; Inhibition; Abdominal motoneuron
• ISSN: 1880-6546; 1880-6562
• DOI: 10.1007/s12576-018-0643-3

Ia excitation and recurrent inhibition are basic neuronal circuits in motor control in hind limb. Renshaw cells receive synaptic inputs from axon collaterals of motoneurons and inhibit motoneurons and Ia inhibitory interneurons. It is important to know properties of Ia excitation and recurrent inhibition of trunk muscle such as abdominal muscles. The abdominal muscles have many roles and change those roles for different kind of functions. Intracellular recordings were obtained from the abdominal motoneurons of the upper lumbar segments in cats anesthetized. First, dorsal roots were left intact, and sensory and motor axons were electrically stimulated. Ia excitatory post-synaptic potentials were elicited in five of eight motoneurons at same segment stimulated. Second, dorsal roots were sectioned, and motor axons were electrically stimulated. Recurrent inhibitory post-synaptic potentials were elicited in one of 11 abdominal motoneurons. Renshaw cells extracellularly fired high-frequency bursts at short latency and at same segment stimulated.