[Retuning of segmental responses to peripheral stimulation during fictive locomotion in cats].
Segmental reflex responses of the lumbosacral spinal cord to peripheral afferent stimulation were investigated in immobilized decorticated cats before and during fictitious locomotion. Appearance of fictitious locomotion was accompanied by an increase of the N1 component of the dorsal cord potential and of the dorsal root potential. Modulation of these responses depending on the phase of fictitious locomotion was observed against a background of their tonic increase. The N1 component and dorsal root potential had larger amplitudes when they appear at the end of the "extensor" phase and at the beginning of the "flexor" phase and smaller amplitudes when they were evoked at the end of the "flexor" phase and at the beginning of the "extensor" phase. Poly- and monosynaptic reflex responses of motoneurons revealed the same phase dependence during fictitious locomotion. Mechanisms and physiological significance of the revealed retuning of segmental reflex responses are discussed on the basis of the obtained data.
D000818:Animals; D002415:Cats; D004558:Electric Stimulation; D004594:Electrophysiology; D008124:Locomotion; D008409:Mastication; D009475:Neurons, Afferent / Q000502:physiology; D012867:Skin / Q000294:innervation; D013116:Spinal Cord / Q000502:physiology*; D013126:Spinal Nerve Roots / Q000502:physiology*; D013569:Synapses / Q000502:physiology; D009435:Synaptic Transmission
Perestroĭka segmentarnykh reaktsiĭ na perifericheskuiu stimuliatsiiu vo vremia fiktivnoĭ lokomotsii u koshki.