Experimental Brain Research

, Volume 18, Issue 3, pp 256–267 | Cite as

Responses to nerve stimulation in the bilateral ventral flexor reflex tract (bVFRT) of the cat

  • Ingmar Rosén
  • Peter Scheid
Article
Received:

Summary

  1. 1.

    93 axons recorded in the ventral part of the lateral funiculus of the spinal cord and activated from bilateral receptive fields as well as from the contralateral ventral quadrant (bVFRT axons) were tested for their responses to stimulation of fore- and hind limb nerves.

     
  2. 2.

    bVFRT neurones with cell bodies in the cervico-thoracic region of the cord were found to respond to stimulation of hind limb afferents as well as forelimb afferents. Similarly bVFRT neurones with cell bodies in the lumbar region responded to stimulation of forelimb afferents via descending spinal paths as well as to hind limb afferents.

     
  3. 3.

    To a large extent the convergence of effects from fore- and hind limb afferents observed in neurones of the lateral reticular nucleus (LRN) (Rosén and Scheid, 1973a) can be explained by a convergence onto bVFRT neurones at segmental levels of the spinal cord. The functional significance of this observation is considered.

     
  4. 4.

    The latencies of excitatory and inhibitory responses in bVFRT axons were compared with those of LRN neurones examined by the same technique. The result supports the conception that LRN receives its main excitatory input from bVFRT.

     

Key words

Spinal cord Afferent pathways to lateral reticular nucleus (bVFRT) 

Abbreviations

C:1

cervical segments 1–2

L:2

lumbar segment 2

VQ

ventral quadrant of the spinal cord at C:3

LF

lateral funiculus of the spinal cord at L:2

i;c

ipsilateral and contralateral, respectively, to recording site For further abbreviations see preceding paper (Rosén and Scheid, 1973a)

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Copyright information

© Springer-Verlag 1973

Authors and Affiliations

  • Ingmar Rosén
    • 1
  • Peter Scheid
    • 1
    • 2
  1. 1.Department of PhysiologySchool of Medicine, State University of New York at BuffaloNew YorkUSA
  2. 2.Abteilung PhysiologieMax-Planck-Institut für experimentelle MedizinGöttingenGermany

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