Skip to main content
PMC home page
The Journal of Physiology logoLink to The Journal of Physiology
. 1984 Nov;356:245–261. doi: 10.1113/jphysiol.1984.sp015462

An intracellular study of descending and non-cutaneous afferent input to spinocervical tract neurones in the cat.

P J Harrison, E Jankowska
PMCID: PMC1193161  PMID: 6097671

Abstract

Previous studies of input on to spinocervical tract neurones have been extended by investigating the post-synaptic actions of non-cutaneous afferent fibres and of descending tracts on to these neurones, using intracellular recording. In particular, actions of group II muscle, joint and Pacinian afferent fibres and rubro- and corticospinal tract fibres were investigated. Group II muscle afferent fibres evoked excitation and inhibition at a minimal latency compatible with a disynaptic linkage. Increasing the stimulus strength to include group III afferent fibres enhanced these post-synaptic actions only modestly. Inhibition was evoked less frequently and/or required trains of stimuli. Weak stimulation of the interosseous nerve evoked short latency (disynaptic) inhibition or excitation, the latter less frequently. Post-synaptic potentials evoked below threshold for group III afferent fibres of the interosseous nerve are attributed to the actions of Pacinian corpuscles. Low threshold joint afferent fibres evoked excitation at short latency. Higher threshold joint afferent fibres usually evoked inhibition at longer latency, although high threshold excitation was sometimes observed. Stimulation of the pyramidal tract evoked constant latency, unitary e.p.s.p.s which followed high frequencies. The evidence suggests that such e.p.s.p.s are evoked monosynaptically. Polysynaptic excitation and inhibition were also observed. No convincing evidence could be found of actions evoked directly by the rubrospinal tract, although actions mediated via other descending systems could be induced from the red nucleus. A large degree of convergence was seen from different peripheral and descending systems on to individual neurones.

Full text

PDF
245

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. ANDERSEN P., ECCLES J. C., SEARS T. A. Presynaptic inhibitory action of cerebral cortex on the spinal cord. Nature. 1962 May 26;194:740–741. doi: 10.1038/194740a0. [DOI] [PubMed] [Google Scholar]
  2. Baldissera F., Lundberg A., Udo M. Stimulation of pre- and postsynaptic elements in the red nucleus. Exp Brain Res. 1972;15(2):151–167. doi: 10.1007/BF00235579. [DOI] [PubMed] [Google Scholar]
  3. Brown A. G. Effects of descending impulses on transmission through the spinocervical tract. J Physiol. 1971 Dec;219(1):103–125. doi: 10.1113/jphysiol.1971.sp009652. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Brown A. G., Franz D. N. Responses of spinocervical tract neurones to natural stimulation of identified cutaneous receptors. Exp Brain Res. 1969;7(3):231–249. doi: 10.1007/BF00239031. [DOI] [PubMed] [Google Scholar]
  5. Brown A. G., Fyffe R. E. Form and function of dorsal horn neurones with axons ascending the dorsal columns in cat. J Physiol. 1981 Dec;321:31–47. doi: 10.1113/jphysiol.1981.sp013970. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Brown A. G., Kirk E. J., Martin H. F., 3rd Descending and segmental inhibition of transmission through the spinocervical tract. J Physiol. 1973 May;230(3):689–705. doi: 10.1113/jphysiol.1973.sp010212. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Brown A. G., Martin H. F., 3rd Activation of descending control of the spinocervical tract by impulses ascending the dorsal columns and relaying through the dorsal column nuclei. J Physiol. 1973 Dec;235(2):535–550. doi: 10.1113/jphysiol.1973.sp010402. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Brown A. G., Short A. D. Effects from the somatic sensory cortex on transmission through the spinocervical tract. Brain Res. 1974 Jul 12;74(2):338–341. doi: 10.1016/0006-8993(74)90588-5. [DOI] [PubMed] [Google Scholar]
  9. Brown A. G. The spinocervical tract. Prog Neurobiol. 1981;17(1-2):59–96. doi: 10.1016/0301-0082(81)90004-6. [DOI] [PubMed] [Google Scholar]
  10. CARPENTER D., LUNDBERG A., NORRSELL U. Effects from the pyramidal tract on primary afferents and on spinal reflex actions to primary afferents. Experientia. 1962 Jul 15;18:337–338. doi: 10.1007/BF02151866. [DOI] [PubMed] [Google Scholar]
  11. Cervero F., Iggo A., Molony V. Responses of spinocervical tract neurones to noxious stimulation of the skin. J Physiol. 1977 May;267(2):537–558. doi: 10.1113/jphysiol.1977.sp011825. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Cole J. D., Gordon G. Timing of corticofugal actions on the gracile and cuneate nuclei of the cat. J Physiol. 1983 Aug;341:139–152. doi: 10.1113/jphysiol.1983.sp014797. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Craig A. D., Jr, Tapper D. N. Lateral cervical nucleus in the cat: functional organization and characteristics. J Neurophysiol. 1978 Nov;41(6):1511–1534. doi: 10.1152/jn.1978.41.6.1511. [DOI] [PubMed] [Google Scholar]
  14. Dart A. M., Gordon G. Some properties of spinal connections of the cat's dorsal column nuclei which do not involve the dorsal columns. Brain Res. 1973 Aug 17;58(1):61–68. doi: 10.1016/0006-8993(73)90823-8. [DOI] [PubMed] [Google Scholar]
  15. Fu T. C., Santini M., Schomburg E. D. Characteristics and distribution of spinal focal synaptic potentials generated by group II muscle afferents. Acta Physiol Scand. 1974 Jul;91(3):298–313. doi: 10.1111/j.1748-1716.1974.tb05686.x. [DOI] [PubMed] [Google Scholar]
  16. HUNT C. C., McINTYRE A. K. Characteristics of responses from receptors from the flexor longus digitorum muscle and the adjoining interosseous region of the cat. J Physiol. 1960 Aug;153:74–87. doi: 10.1113/jphysiol.1960.sp006519. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Hamann W. C., Hong S. K., Kniffki K. D., Schmidt R. F. Projections of primary afferent fibres from muscle to neurones of the spinocervical tract of the cat. J Physiol. 1978 Oct;283:369–378. doi: 10.1113/jphysiol.1978.sp012506. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Harrison P. J., Johannisson T. Segmental actions of afferents of the interosseous nerve in the cat. J Physiol. 1983 Dec;345:373–389. doi: 10.1113/jphysiol.1983.sp014983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Harrison P. J., Taylor A. Individual excitatory post-synaptic potentials due to muscle spindle Ia afferents in cat triceps surae motoneurones. J Physiol. 1981 Mar;312:455–470. doi: 10.1113/jphysiol.1981.sp013638. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Hong S. K., Kniffke K. D., Mense S., Schmidt R. F., Wendisch M. Descending influences on the responses of spinocervical tract neurones to chemical stimulation of fine muscle afferents. J Physiol. 1979 May;290(2):129–140. doi: 10.1113/jphysiol.1979.sp012764. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Hongo T., Jankowska E., Lundberg A. Post-synaptic excitation and inhibition from primary afferents in neurones of the spinocervical tract. J Physiol. 1968 Dec;199(3):569–592. doi: 10.1113/jphysiol.1968.sp008669. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Hongo T., Jankowska E., Lundberg A. The rubrospinal tract. I. Effects on alpha-motoneurones innervating hindlimb muscles in cats. Exp Brain Res. 1969;7(4):344–364. doi: 10.1007/BF00237320. [DOI] [PubMed] [Google Scholar]
  23. Jankowska E., Rastad J., Zarzecki P. Segmental and supraspinal input to cells of origin of non-primary fibres in the feline dorsal columns. J Physiol. 1979 May;290(2):185–200. doi: 10.1113/jphysiol.1979.sp012767. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Jeneskog T., Johansson H. The rubro-bulbospinal path. A descending system known to influence dynamic fusimotor neurones and its interaction with distal cutaneous afferents in the control of flexor reflex afferent pathways. Exp Brain Res. 1977 Feb 16;27(2):161–179. doi: 10.1007/BF00237696. [DOI] [PubMed] [Google Scholar]
  25. Kirkwood P. A., Sears T. A. Excitatory post-synaptic potentials from single muscle spindle afferents in external intercostal motoneurones of the cat. J Physiol. 1982 Jan;322:287–314. doi: 10.1113/jphysiol.1982.sp014038. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Kniffki K. D., Mense S., Schmidt R. F. The spinocervical tract as a possible pathway for muscular nociception. J Physiol (Paris) 1977 Sep;73(3):359–366. [PubMed] [Google Scholar]
  27. LUNDBERG A., NORRSELL U., VOORHOEVE P. EFFECTS FROM THE SENSORIMOTOR CORTEX ON ASCENDING SPINAL PATHWAYS. Acta Physiol Scand. 1963 Dec;59:462–473. doi: 10.1111/j.1748-1716.1963.tb02762.x. [DOI] [PubMed] [Google Scholar]
  28. LUNDBERG A., VOORHOEVE P. Effects from the pyramidal tract on spinal reflex arcs. Acta Physiol Scand. 1962 Nov-Dec;56:201–219. doi: 10.1111/j.1748-1716.1962.tb02498.x. [DOI] [PubMed] [Google Scholar]
  29. Lundberg A., Malmgren K., Schomburg E. D. Characteristics of the excitatory pathway from group II muscle afferents to alpha motoneurones. Brain Res. 1975 May 9;88(3):538–542. doi: 10.1016/0006-8993(75)90667-8. [DOI] [PubMed] [Google Scholar]
  30. Lüscher H. R., Ruenzel P., Fetz E., Henneman E. Postsynatpic population potentials recorded from ventral roots perfused with isotonic sucrose: connections of groups Ia and II spindle afferent fibers with large populations of motoneurons. J Neurophysiol. 1979 Jul;42(4):1146–1164. doi: 10.1152/jn.1979.42.4.1146. [DOI] [PubMed] [Google Scholar]
  31. Mendell L. M., Henneman E. Terminals of single Ia fibers: location, density, and distribution within a pool of 300 homonymous motoneurons. J Neurophysiol. 1971 Jan;34(1):171–187. doi: 10.1152/jn.1971.34.1.171. [DOI] [PubMed] [Google Scholar]
  32. Muir R. B., Porter R. The effect of a preceding stimulus on temporal facilitation at corticomotoneuronal synapses. J Physiol. 1973 Feb;228(3):749–763. doi: 10.1113/jphysiol.1973.sp010110. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. NYBERG-HANSEN R., BRODAL A. Sites of termination of corticospinal fibers in the cat. An experimental study with silver impregnation methods. J Comp Neurol. 1963 Jun;120:369–391. doi: 10.1002/cne.901200302. [DOI] [PubMed] [Google Scholar]
  34. Porter R. Early facilitation at corticomotoneuronal synapses. J Physiol. 1970 May;207(3):733–745. doi: 10.1113/jphysiol.1970.sp009091. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. TAUB A., BISHOP P. O. THE SPINOCERVICAL TRACT: DORSAL COLUMN LINKAGE, CONDUCTION VELOCITY, PRIMARY AFFERENT SPECTRUM. Exp Neurol. 1965 Sep;13:1–21. doi: 10.1016/0014-4886(65)90002-6. [DOI] [PubMed] [Google Scholar]

Articles from The Journal of Physiology are provided here courtesy of The Physiological Society

RESOURCES