QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

This Article Full Text Full Text (PDF) Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (24) Citing Articles via Google Scholar Google Scholar Articles by Woodbury, C. J. Articles by Koerber, H. R. Search for Related Content PubMed PubMed Citation Articles by Woodbury, C. J. Articles by Koerber, H. R.

 Previous Article  |  Next Article 

The Journal of Neuroscience, January 15, 2003, 23(2):601-610

Widespread Projections from Myelinated Nociceptors throughout the Substantia Gelatinosa Provide Novel Insights into Neonatal Hypersensitivity

C. Jeffery Woodbury and H. Richard Koerber

Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261

Skin sensory neurons have long been thought to undergo major changes in anatomy and physiology over the first few weeks of postnatal life. Low-threshold mechanoreceptors (LTMRs) are believed to project extensively throughout superficial dorsal horn laminas initially and provide the afferent limb for hyperactive nocifensive reflexes. However, our recent studies revealed that neonatal LTMRs do not project into "pain-specific" regions; instead, they exhibit adult-like anatomy shortly after birth. We sought to determine whether the same might be true for myelinated high-threshold mechanoreceptors (HTMRs). We used an intact, ex vivo somatosensory system preparation from neonatal mice to allow intrasomal recording and neurobiotin labeling of individual sensory neurons characterized via natural skin stimuli. Neonatal HTMRs displayed a number of key hallmarks of their adult counterparts; relative to LTMRs, they exhibited broader, inflected somal spikes and higher mechanical thresholds and/or responded in an increasingly vigorous manner to incrementally graded forces in a manner capable of encoding stimulus intensity. Two types were discerned on the basis of central anatomy: one subset projected to superficial laminas (I/II); the other gave rise to diffuse, dorsally recurving collateral arbors extending throughout the entire dorsal horn (I-V). The latter represent a novel cutaneous afferent morphology that persists in older animals. These studies reveal that inputs from myelinated afferents to superficial pain-specific laminas in neonates arise from HTMRs and not LTMRs as commonly thought. This frequently overlooked population is in a position, therefore, to contribute substantially to paradoxical nocifensive behaviors in neonates and various pain states in adults.

Key words: pain; development; spinal cord; dorsal horn; lamina II; skin; sensory; dorsal root ganglia; DRG

---

Copyright © 2003 Society for Neuroscience  0270-6474/03/232601-10$05.00/0

This article has been cited by other articles:

				M. D. Boada and C. J. Woodbury Myelinated Skin Sensory Neurons Project Extensively throughout Adult Mouse Substantia Gelatinosa J. Neurosci., February 27, 2008; 28(9): 2006 - 2014. [Abstract] [Full Text] [PDF]

				M. D. Boada and C. J. Woodbury Physiological Properties of Mouse Skin Sensory Neurons Recorded Intracellularly In Vivo: Temperature Effects on Somal Membrane Properties J Neurophysiol, August 1, 2007; 98(2): 668 - 680. [Abstract] [Full Text] [PDF]

				J. Hu and G. R. Lewin Mechanosensitive currents in the neurites of cultured mouse sensory neurones J. Physiol., December 15, 2006; 577(3): 815 - 828. [Abstract] [Full Text] [PDF]

				C. M. Elitt, S. L. McIlwrath, J. J. Lawson, S. A. Malin, D. C. Molliver, P. K. Cornuet, H. R. Koerber, B. M. Davis, and K. M. Albers Artemin Overexpression in Skin Enhances Expression of TRPV1 and TRPA1 in Cutaneous Sensory Neurons and Leads to Behavioral Sensitivity to Heat and Cold. J. Neurosci., August 15, 2006; 26(33): 8578 - 8587. [Abstract] [Full Text] [PDF]

				C. J. Woodbury, M. Zwick, S. Wang, J. J. Lawson, M. J. Caterina, M. Koltzenburg, K. M. Albers, H. R. Koerber, and B. M. Davis Nociceptors Lacking TRPV1 and TRPV2 Have Normal Heat Responses J. Neurosci., July 14, 2004; 24(28): 6410 - 6415. [Abstract] [Full Text] [PDF]

				A. R. Light "Nocifensor" System Re-Revisited. Focus on "Two Types of C Nociceptor in Human Skin and Their Behavior in Areas of Capaicin-Induced Secondary Hyperalgesia" J Neurophysiol, June 1, 2004; 91(6): 2401 - 2403. [Full Text] [PDF]

				D. I. Hughes, D. T. Scott, A. J. Todd, and J. S. Riddell Lack of Evidence for Sprouting of A{beta} Afferents into the Superficial Laminas of the Spinal Cord Dorsal Horn after Nerve Section J. Neurosci., October 22, 2003; 23(29): 9491 - 9499. [Abstract] [Full Text] [PDF]

				M. Shoykhet, P. Shetty, B. S. Minnery, and D. J. Simons Protracted Development of Responses to Whisker Deflection in Rat Trigeminal Ganglion Neurons J Neurophysiol, September 1, 2003; 90(3): 1432 - 1437. [Abstract] [Full Text] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help