HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 546/2/565    most recent 2002.026559v1 Services Email this article to a friend Similar articles in this journal 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 Google Scholar Google Scholar Articles by Djouhri, L. Articles by Lawson, S. N. Search for Related Content PubMed PubMed Citation Articles by Djouhri, L. Articles by Lawson, S. N.

Sensory and electrophysiological properties of guinea-pig sensory neurones expressing Na_v1.7 (PN1) Na⁺ channel subunit protein

Laiche Djouhri*, Richard Newton*, Simon Rock Levinson†, Carol M. Berry*, Barbara Carruthers* and Sally N. Lawson*

The TTX-sensitive Na_v1.7 (PN1) Na⁺ channel subunit protein is expressed mainly in small dorsal root ganglion (DRG) neurones. This study examines immunocytochemically whether it is expressed exclusively or preferentially in nociceptive primary afferent DRG neurones, and determines the electrophysiological properties of neurones that express it. Intracellular somatic action potentials (APs) evoked by dorsal root stimulation were recorded in L6/S1 DRG neurones at 30 ± 2 °C in vivo in deeply anaesthetised young guinea-pigs. Each neurone was classified, from its dorsal root conduction velocity (CV) as a C-, A- or A/-fibre unit and from its response to mechanical and thermal stimuli, as a nociceptive, low threshold mechanoreceptive (LTM) or unresponsive unit. Fluorescent dye was injected into the soma and Na_v1.7-like immunoreactivity (Na_v1.7-LI) was examined on sections of dye-injected neurones. All C-, 90 % of A- and 40 % of A/-fibre units, including both nociceptive and LTM units, showed Na_v1.7-LI. Positive units included 1/1 C-LTM, 6/6 C-nociceptive, 4/4 C-unresponsive (possible silent nociceptive) units, 5/6 A-LTM (D hair), 13/14 A-nociceptive, 2/9 A/-nociceptive, 10/18 A/-LTM cutaneous and 0/9 A/-muscle spindle afferent units. Overall, a higher proportion of nociceptive than of LTM neurones was positive, and the median relative staining intensity was greater in nociceptive than LTM units. Na_v1.7-LI intensity was clearly positively correlated with AP duration and (less strongly) negatively correlated with CV and soma size. Since nociceptive units tend overall to have longer duration APs, slower CVs and smaller somata, these correlations may be related to the generally greater expression of Na_v1.7 in nociceptive units.

This article has been cited by other articles:

				W. A. Catterall, S. Dib-Hajj, M. H. Meisler, and D. Pietrobon Inherited Neuronal Ion Channelopathies: New Windows on Complex Neurological Diseases J. Neurosci., November 12, 2008; 28(46): 11768 - 11777. [Abstract] [Full Text] [PDF]

				W. A. Schmalhofer, J. Calhoun, R. Burrows, T. Bailey, M. G. Kohler, A. B. Weinglass, G. J. Kaczorowski, M. L. Garcia, M. Koltzenburg, and B. T. Priest ProTx-II, a Selective Inhibitor of NaV1.7 Sodium Channels, Blocks Action Potential Propagation in Nociceptors Mol. Pharmacol., November 1, 2008; 74(5): 1476 - 1484. [Abstract] [Full Text] [PDF]

				M. Estacion, S. D. Dib-Hajj, P. J. Benke, R. H. M. te Morsche, E. M. Eastman, L. J. Macala, J. P. H. Drenth, and S. G. Waxman NaV1.7 Gain-of-Function Mutations as a Continuum: A1632E Displays Physiological Changes Associated with Erythromelalgia and Paroxysmal Extreme Pain Disorder Mutations and Produces Symptoms of Both Disorders J. Neurosci., October 22, 2008; 28(43): 11079 - 11088. [Abstract] [Full Text] [PDF]

				P. L. Sheets, J. O. Jackson II, S. G. Waxman, S. D. Dib-Hajj, and T. R. Cummins A Nav1.7 channel mutation associated with hereditary erythromelalgia contributes to neuronal hyperexcitability and displays reduced lidocaine sensitivity J. Physiol., June 15, 2007; 581(3): 1019 - 1031. [Abstract] [Full Text] [PDF]

				A. M. Rush, T. R. Cummins, and S. G. Waxman Multiple sodium channels and their roles in electrogenesis within dorsal root ganglion neurons J. Physiol., February 15, 2007; 579(1): 1 - 14. [Abstract] [Full Text] [PDF]

				W. Xie, J. A. Strong, H. Li, and J.-M. Zhang Sympathetic Sprouting Near Sensory Neurons After Nerve Injury Occurs Preferentially on Spontaneously Active Cells and Is Reduced by Early Nerve Block J Neurophysiol, January 1, 2007; 97(1): 492 - 502. [Abstract] [Full Text] [PDF]

				X. Fang, L. Djouhri, S. McMullan, C. Berry, S. G. Waxman, K. Okuse, and S. N. Lawson Intense isolectin-B4 binding in rat dorsal root ganglion neurons distinguishes C-fiber nociceptors with broad action potentials and high Nav1.9 expression. J. Neurosci., July 5, 2006; 26(27): 7281 - 7292. [Abstract] [Full Text] [PDF]

				S. D. Dib-Hajj, A. M. Rush, T. R. Cummins, F. M. Hisama, S. Novella, L. Tyrrell, L. Marshall, and S. G. Waxman Gain-of-function mutation in Nav1.7 in familial erythromelalgia induces bursting of sensory neurons Brain, August 1, 2005; 128(8): 1847 - 1854. [Abstract] [Full Text] [PDF]

				X Fang, S McMullan, S. N Lawson, and L Djouhri Electrophysiological differences between nociceptive and non-nociceptive dorsal root ganglion neurones in the rat in vivo J. Physiol., June 15, 2005; 565(3): 927 - 943. [Abstract] [Full Text] [PDF]

				X. Fang, L. Djouhri, S. McMullan, C. Berry, K. Okuse, S. G. Waxman, and S. N. Lawson trkA Is Expressed in Nociceptive Neurons and Influences Electrophysiological Properties via Nav1.8 Expression in Rapidly Conducting Nociceptors J. Neurosci., May 11, 2005; 25(19): 4868 - 4878. [Abstract] [Full Text] [PDF]

				T. R. Cummins, S. D. Dib-Hajj, and S. G. Waxman Electrophysiological Properties of Mutant Nav1.7 Sodium Channels in a Painful Inherited Neuropathy J. Neurosci., September 22, 2004; 24(38): 8232 - 8236. [Abstract] [Full Text] [PDF]

				M. A. Nassar, L. C. Stirling, G. Forlani, M. D. Baker, E. A. Matthews, A. H. Dickenson, and J. N. Wood Nociceptor-specific gene deletion reveals a major role for Nav1.7 (PN1) in acute and inflammatory pain PNAS, August 24, 2004; 101(34): 12706 - 12711. [Abstract] [Full Text] [PDF]

				S. Hong, T. J. Morrow, P. E. Paulson, L. L. Isom, and J. W. Wiley Early Painful Diabetic Neuropathy Is Associated with Differential Changes in Tetrodotoxin-sensitive and -resistant Sodium Channels in Dorsal Root Ganglion Neurons in the Rat J. Biol. Chem., July 9, 2004; 279(28): 29341 - 29350. [Abstract] [Full Text] [PDF]