Distribution of Unmyelinated Primary Afferent Fibers in the Dorsal Horn

  • Y. Sugiura
  • N. Terui
  • Y. Hosoya
  • K. Kohno


Primary afferent neurons with fibers in peripheral nerve encode sensory information from many tissues and organs. They represent the first step in processing information about peripheral events. Peripheral afferent fibers can be divided into two major groups on the basis of size and structure, myelinated or unmyelinated. These two categories account for the principal conduction velocity subsets, A (myelinated) and C (unmyelinated) of both somatic and visceral afferent fibers.


Dorsal Root Ganglion Dorsal Horn Afferent Fiber Superficial Dorsal Horn Unmyelinated Fiber 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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  1. ABRAHAMS, V.C., RICHMOND, F.J. AND KEANE, J. (1984) Projections from C2 and C3 nerves supplying muscles and skin of the cat neck: A study using transganglionic transport of horseradish peroxidase. Journal of Comparative Neurology 230, 142–154.CrossRefGoogle Scholar
  2. ARVIDSSON, J. AND THOMANDER, L. (1984) An HRP study of the central course of sensory intermediate and vagal fibers in peripheral facial nerve branches in the cat., Journal of Comparative Neurology 223, 35–45.CrossRefGoogle Scholar
  3. BEACHAM, W.S. and KUNZE, D.L. (1969) Renal receptors evoking a spinal vasometer reflex. Journal of Physiology 201, 73–85.Google Scholar
  4. BESSOU, P. and PERL, E.R. (1966) A movement receptor of the small intestine., Journal of Physiology 182, 404–426.Google Scholar
  5. BESSOU, P. and PERL, E.R. (1969) Response of cutaneous sensory units with unmyelinated fibers to noxious stimuli. Journal of Neurophysiology 32, 1025–1043.Google Scholar
  6. BROWN, A.G. (1981a) The terminations of cutaneous nerve fibers in the spinal cord. Trends in Neuroscience 4, 64–67.CrossRefGoogle Scholar
  7. BROWN, A.G., (1981b) Organization in the spinal cord. Springer-Verlag. New York.Google Scholar
  8. BROWN, A.G. and FYFFE, R.E.W. (1977) The morphology of group la afferent fibre collaterals in the spinal cord of the cat., Journal of Physiology 274, 111–127.Google Scholar
  9. BROWN, A.G. and FYFFE, R.E.W. (1979) The morphology of group lb afferent fibre collaterals in the spinal cord of the cat. Journal of Physiology 296, 215–228.Google Scholar
  10. CERVERO, F. (1983) Somatic and visceral inputs to the thoracic spinal cord of the cat: effects of noxious stimulation of the biliary system., Journal of Physiology 337, 51–67.Google Scholar
  11. CERVERO, F. and CONNELL, L.A. (1984a) Fine afferent fibers from viscera do not terminate in the substantia gelatinosa of the thoracic spinal cord. Brain Research 294, 370–374.CrossRefGoogle Scholar
  12. CERVERO, F. and CONNELL, L.A. (1984b) Distribution of somatic and visceral primary afferent fibres within the thoracic spinal cord of the cat, Journal of Comparative Neurology 230, 88–98.CrossRefGoogle Scholar
  13. CERVERO, F. and TATTERSALL, J.E.H., (1987) Somatic and visceral inputs to the thoracic spinal cord of the cat: Marginal zone (lamina I) of the dorsal horn., Journal of Physiology 383, 383–395.Google Scholar
  14. CIRIELLO, J. and CALARESU, F.R., (1983). Central projections of afferent renal fibers in the rat: An anterograde transport study of horseradish peroxidase. Journal of the Autonomic Nervous System 8, 273–285.CrossRefGoogle Scholar
  15. CRAIG, A.D. and KNIFFKI, K.D., (1985). Spinothalamic lumbosacral lamina I cells responsive to skin and muscle stimulation in the cat. Journal of Physiology 365, 197–221.Google Scholar
  16. CRAIG, A.D. and MENSE, S. (1983) The distribution of afferent fibers from the gastrocnemius-soleus in the dorsal horn of the cat, as revealed by the transport of horseradish peroxidase. Neuroscience Letters 41, 233–238.CrossRefGoogle Scholar
  17. DEGROAT, W.C., NADELHAFT, I., MORGAN, C. and SCHAUBLE, T. (1978) Horseradish peroxidase tracing of visceral efferent and primary afferent pathways in the cats sacral spinal cord using benzidine processing. Neuroscience Letters 10, 103–108.CrossRefGoogle Scholar
  18. EARLE, K.M., (1952) The tract of Lissauer and its possible relation to the pain pathway. Journal of Comparative Neurology 96, 93–111.CrossRefGoogle Scholar
  19. FIELDS, H.L., MEYER, G.A. and PARTRIDGE, Jr., L.D. (1970) Convergence of visceral and somatic input onto spinal neurons. Experimental Neurology 26, 36–52.CrossRefGoogle Scholar
  20. FITZGERALD, M. (1984) The course and termination of primary afferent fibres. In Textbook of Pain, eds. WALL, P.D., MELZACK, R., Churchill, Livingstone.Google Scholar
  21. FYFFE, R.E.W. (1984) Afferent fibres. In Handbook of the Spinal Cord Vol. 2 and 3., ed. Davidoff, R.A. pp. 79–136. New York: Marcel Dekker.Google Scholar
  22. GERFEN, C.R. and SAWACHENKO, P.E., (1984). An anterograde neuroanatomical tracing method that shows the detailed morphology of neurons, their axons and terminals: Immunohistochemical localization of an axonally transported plant lectin, phaseolus vulgaris leucoagglutinin (PHA-L). Brain Research 290, 219–238.CrossRefGoogle Scholar
  23. GOBEL, S., FALL, W.M. and HUMPHREY, E. (1981). Morphology and synaptic connections of ultrafine primary axons in lamina I of the spinal dorsal horn: Candidates for the terminal axonal arbors of primary neurons with unmyelinated (C) axon. Journal of Neuroscience 1, 1163–1179.Google Scholar
  24. HARPER, A.A. and LAWSON, S.N. (1985) Conduction velocity is related to morphological cell type in rat dorsal root ganglion neurones. Journal of Physiology 359, 31–46.Google Scholar
  25. HSU, S.-H., RAINE, L. and FANGER, H., (1981a) The use of avidin-bioitinperoxidase complex (ABC) in immunoperoxidase techniques: A comparison between ABC and unlabelled antibody (PAP) procedures. Journal of Histochemistry and Cytochemistry 29, 577–580.CrossRefGoogle Scholar
  26. HSU, S.-H., RAINE, L., FANGER, H., (1981b) A comparative study of the peroxidase-antiperoxidase method and an avidine-biotin complex method for studying polypeptide hormones with radioimmunoassay antibodies. American Journal of Clinical Pathology 75, 734–738.Google Scholar
  27. ISHIZUKA, N., MANNEN, H., HONGO, T. and SASAKI, S. (1979) Trajectory of group la afferent fibers stained with horseradish peroxidase in the lumbosacral spinal cord of the cat: Three dimensional reconstructions from serial sections., Journal of Comparative Neurology 186, 189–212.CrossRefGoogle Scholar
  28. JANIG, W. and MORRISON, J.F.B. (1986) Functional properties of spinal visceral afferent supplying abdominal and pelvic organs, with special emphasis on visceral nociception., Progress in Brain Research 67, 87–114 eds. CERVERO, F., Morrison, J.F.B. Elsevier, Amsterdam.Google Scholar
  29. KUMAZAWA, T. and PERL, E.R. (1977) Primate cutaneous sensory units with unmyelinated (C) afferent fibers., Journal of Neurophysiology 40, 1325–1338.Google Scholar
  30. KUO, D.C. and NADELHAFT, I., HISAMITSU, T. and DEGROAT, W.C. (1983) Segmental distribution and central projections of renal afferent fibers in the cat studied by transganglionic transport of horseradish peroxidase. Journal of Comparative Neurology, 216, 162–174.Google Scholar
  31. LIGHT, A.R. and PERL, E.R., (1979) Spinal termination of functionally identified primary afferent neurons with slowly conducting myelinated fibers. Journal of Comparative Neurology 186, 133–150.CrossRefGoogle Scholar
  32. MENSE, S. and PROBHAKAR, N.R. (1986) Spinal termination of nociceptive afferent fibers from deep tissues in the cat., Neuroscience Letters 66, 169–174.CrossRefGoogle Scholar
  33. MOLANDRER, C. and GRANT, G. (1987) Spinal cord projections form hindlimb muscle nerves in the rat studied by transganglionic transport of horseradish peroxidase, wheat germ agglutinin conjugated horseradish peroxidase, or horseradish peroxidase with dimethylsulfoxide. Journal of Comparative Neurology 260, 246–255.CrossRefGoogle Scholar
  34. MORGAN, C., DEGROAT, W.C. and NADELHAFT, I. (1986). The spinal distribution of sympathetic preganglionic and visceral primary afferent neurons that send axons into the hypogastric nerves of the cat. Journal of Comparative Neurology 243, 23–40.CrossRefGoogle Scholar
  35. MORGAN, C., NADELHAFT, I. and DEGROAT, W.C. (1981) The distribution of visceral primary afferents from the pelvic nerve to Lissauer’s tract and the spinal gray matter and its relationship to the sacral parasympathetic nucleus. Journal of Comparative Neurology 201, 415–440.CrossRefGoogle Scholar
  36. MOSS, N.G. (1987) Electrophysiological characteristics of sensory mechanisms in the kidney., In Clinical and Experimental HypertensionPart A: Theory and Practice, ed. Slater, I.H., pp. 1–13. New York: Marcel Dekker, Inc.Google Scholar
  37. NADELHAFT, I. and BOOTH, A.M., (1984). The location and morphology of preganglionic neurons and the distribution of visceral afferents from the rat pelvic nerve: A horseradish peroxidase study. Journal of Comparative Neurology 226, 238–245.CrossRefGoogle Scholar
  38. NADELHAFT, I., ROPPOLO, J., MORGAN, C. and DEGROAT, W.C. (1983). Parasympathetic preganglionic neurons and visceral primary afferents in monkey sacral spinal cord revealed following application of horseradish peroxidase to pelvic nerve. Journal of Comparative Neurology 216, 36–52.CrossRefGoogle Scholar
  39. NESS, T.J. and GEBHART, G.H. (1987) Characterization of neuronal responses to noxious visceral and somatic stimuli in the medial lumbosacral spinal cord of rat. Journal of Neurophysiology 57, 1867–1892.Google Scholar
  40. NUNEZ, R., GROSS, G.H. and SACHS, B.D., (1986). Origin and central projections of rat dorsal penile nerve: Possible direct projection to autonomic and somatic neurons by primary afferents of nonmuscle origin. Journal of Comparative Neurology 247, 417–429.CrossRefGoogle Scholar
  41. POMERANZ, B., WALL, P.D. and WEBER, W.V. (1968) Cord cells responding to fine myelinated afferents from viscera, muscle and skin., Journal of Physiology 199, 511–532.Google Scholar
  42. RÉTHELYI, M. (1977) Preterminal and terminal axon arborizations in the substantia gelatinosa of cat’s spinal cord., Journal of Comparative Neurology 172, 511–527.CrossRefGoogle Scholar
  43. REXED, B. (1952) The cytoarchitectonic organization of the spinal cord in the cat. Journal of Comparative Neurology 96, 415–495.CrossRefGoogle Scholar
  44. PIERAU, F.-K., FELLMER, G. and TAYLOR, D.C.M. (1984) Somato-visceral convergence in cat dorsal root ganglion neurones demonstrated by double- labelling with fluorescent tracers., Brain Research 321, 63–70.CrossRefGoogle Scholar
  45. SAWACHENKO, P.E. and GERFEN, C.R. (1985) Plant lectins and bacterial toxins as tools for tracing neuronal connections., Trends in Neuroscience 8, 378–384.CrossRefGoogle Scholar
  46. SELZER, M. and SPENCER, W.A. (1969a) Convergence of visceral and cutaneous afferent pathways in the lumbar spinal cord., Brain Research 14, 331–348.CrossRefGoogle Scholar
  47. SELZER, M. and SPENCER, W.A. (1969b) Interactions between visceral and cutaneous afferent in the spinal cord: Reciprocal primary afferent fiber depolarization., Brain Research 14,349 –366.CrossRefGoogle Scholar
  48. SHARKEY, K.A., WILLIAMS, P.G., SHULTZBERG, M. and DOCKRAY, G.J. (1983) Sensory substance P-innervation of the urinary bladder: Possible site of action of capsaicin in causing urine retention in rats., Neuroscience 10, 861–868.CrossRefGoogle Scholar
  49. SHEA, V.K. and PERL, E.R. (1985) Sensory receptors with unmyelinated (C) fibers innervating the skin of the rabbit’s ear., Journal of Neurophysiology 54, 491–501.Google Scholar
  50. SNOW, P.J., ROSE, P.K. and BROWN, A.G. (1976) Tracing axon and axon collaterals of spinal neurons using intracellular injection of horseradish peroxidase., Science 191, 312–313.CrossRefGoogle Scholar
  51. SPRAGUE, J.M. and HA, H. (1964) The terminal fields of dorsal root fibers in the lumbosacral spinal cord of the cat, and the dendritic organization of the motor nuclei. In Organization of the Spinal Cord., eds., Eccles, J.C., Schade, J.P., pp. 120–154. Amsterdam: Elsevier.CrossRefGoogle Scholar
  52. SUGIURA, Y., HOSOYO, Y., ITO, R. AND KOHNO, K. (1988). Ultrastructural features of functionally identified primary afferent neurons with C (unmyelinated) fibers of the guinea pig. Classification of dorsal root ganglion cell type with reference to sensory modality. Journal of Comparative Neurology, (in press).Google Scholar
  53. SUGIURA, Y., LEE, C.L. and PERL, E.R. (1986) Central projections of identified, unmyelinated (C) afferent fibers innervating mammalian skin. Science 234, 358–361.CrossRefGoogle Scholar
  54. SUGIURA, Y., SCHRANK, E. and PERL, E.R., (1985) Central terminal distribution of unmyelinated afferent fibers., Society of Neuroscience Abstract 11, 118.Google Scholar
  55. SZENTAGOTHAI, J. (1964). Neuronal and synaptic arrangement in the substantia gelatinosa Rolandi., Journal of Comparative Neurology 122, 219–239.CrossRefGoogle Scholar
  56. TER HORST, G.J., GROENWEGEN, H.J., KARUST, H. and LUITEN, P.G.M. (1985) Phaseolus vulgaris leukoagglutinin immunocytochemistry., A comparison between autoradiographic and lectin tracing neuronal efferents. Brain Research 307, 379–383.CrossRefGoogle Scholar

Copyright information

© Plenum Press 1989

Authors and Affiliations

  • Y. Sugiura
    • 1
    • 2
  • N. Terui
    • 1
  • Y. Hosoya
    • 1
  • K. Kohno
    • 1
  1. 1.Institute of Basic Medical SciencesUniversity of TsukubaTsukuba, IbarakiJapan
  2. 2.Department of AnatomyFukushima Medical CollegeFukushima City, FukushimaJapan

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