Polysynaptic pathways from high threshold muscle afferents innervating hindlimb muscles to tail motoneurons in the spinalized cat.

Abstract

The postsynaptic potentials (PSPs) after stimulating hindlimb flexor (PBSt) and extensor muscle nerves (LGS) were recorded from 64 tail motoneurons innervating m. extensor caudae lateralis and m. flexor caudae longus in the spinalized cats. Postsynaptic potentials were produced after stimulating high threshold muscle afferent fibers (group II and group III) and the average central latencies of PSPs were distributed in a wide range between 4.5 and 15.1 ms. Opposite effects on tail motoneurons were observed between stimulation of flexor and extensor muscle nerves, or ipsilateral and contralateral muscle nerves.