[The facilitation of transmission in the 1a inhibition pathway to the lumbar extensor motoneurons during stimulation of the nerves of the cat forelimbs].
Activation of forelimb flexor reflex afferents (FRA) exerted a facilitating effect upon the reciprocal 1a IPSP recorded in extensor motoneurones of lumbosacral segments. The latency of this spatial facilitation was 18-20 ms, duration up to 60 ms, the amplitude of the test disynaptic 1a IPSP being several times greater than in the control. Facilitation of the 1a IPSP occurs against the background of the IPSP evoked by descending interlimb impulses. Therefore the facilitation of synaptic transmission in the 1a inhibitory pathway to extensor motoneurones induced by the descending interlimb volleys, favours more pronounced reciprocal interrelations between flexor and extensor spinal motor centres.
Avelev
V D
VD
I. P. Pavlov Institue of Physiology, Russian Acad. Sci., St. Petersburg, Russia.
D000818:Animals; D002415:Cats; D004558:Electric Stimulation; D005071:Evoked Potentials / Q000502:physiology; D005552:Forelimb / Q000294:innervation; D007395:Interneurons / Q000502:physiology; D007796:Laminectomy; D008161:Lumbosacral Region / Q000294:innervation; D008839:Microelectrodes; D009046:Motor Neurons / Q000502:physiology*; D009433:Neural Inhibition / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology*