JN Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Neurophysiol 81: 413-424, 1999;
0022-3077/99 $5.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Strassman, A. M.
Right arrow Articles by Raymond, S. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Strassman, A. M.
Right arrow Articles by Raymond, S. A.

The Journal of Neurophysiology Vol. 81 No. 2 February 1999, pp. 413-424
Copyright ©1999 by the American Physiological Society

Electrophysiological Evidence for Tetrodotoxin-Resistant Sodium Channels in Slowly Conducting Dural Sensory Fibers

A. M. Strassman1,3 and S. A. Raymond2,3

 1Department of Anesthesia, Beth Israel Deaconess Medical Center;  2Brigham and Women's Hospital; and  3Harvard Medical School, Boston, Massachusetts 02215

Electrophysiological evidence for tetrodotoxin-resistant sodium channels in mechanosensitive nerve endings of slowly conducting fibers in the intracranial dura. A tetrodotoxin (TTX)-resistant sodium channel was recently identified that is expressed only in small diameter neurons of peripheral sensory ganglia. The peripheral axons of sensory neurons appear to lack this channel, but its presence has not been investigated in peripheral nerve endings, the site of sensory transduction in vivo. We investigated the effect of TTX on mechanoresponsiveness in nerve endings of sensory neurons that innervate the intracranial dura. Because the degree of TTX resistance of axonal branches could potentially be affected by factors other than channel subtype, the neurons were also tested for sensitivity to lidocaine, which blocks both TTX-sensitive and TTX-resistant sodium channels. Single-unit activity was recorded from dural afferent neurons in the trigeminal ganglion of urethan-anesthetized rats. Response thresholds to mechanical stimulation of the dura were determined with von Frey monofilaments while exposing the dura to progressively increasing concentrations of TTX or lidocaine. Neurons with slowly conducting axons were relatively resistant to TTX. Application of 1 µM TTX produced complete suppression of mechanoresponsiveness in all (11/11) fast A-delta units [conduction velocity (c.v.) 5-18 m/s] but only 50% (5/10) of slow A-delta units (1.5 <c.v.<5 m/s) and 13% (2/15) of C units (c.v. <= 1.5 m/s). The mean TTX concentration that produced complete suppression of mechanoresponsiveness was ~270-fold higher in C units than in fast A-delta units. In contrast, no significant difference was found between C and A-delta units in the concentration of lidocaine required for complete suppression of mechanoresponsiveness, indicating that the greater TTX resistance of mechanoresponsiveness in C units is not attributable to differences in safety factor unrelated to channel subtype. These data offer indirect evidence that a TTX-resistant channel subtype is expressed in the terminal axonal branches of many of the more slowly conducting (C and slow A-delta ) dural afferents. The channel appears to be present in these fibers, but not in the faster A-delta fibers, in sufficient numbers to support the initiation and propagation of mechanically induced impulses. Comparison with previous data on the absence of TTX resistance in peripheral nerve fibers suggests that the TTX-resistant sodium channel may be a distinctive feature of the receptive rather than the conductive portion of the sensory neuron's axonal membrane.

0022-3077/99 $5.00 Copyright © 1999 The American Physiological Society



This article has been cited by other articles:


Home page
 J. Neurophysiol.Home page
V. Pinto, V. A. Derkach, and B. V. Safronov
Role of TTX-Sensitive and TTX-Resistant Sodium Channels in A{delta}- and C-Fiber Conduction and Synaptic Transmission
J Neurophysiol, February 1, 2008; 99(2): 617 - 628.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
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]

Home page
 Proc. Natl. Acad. Sci. USAHome page
J. Ekberg, A. Jayamanne, C. W. Vaughan, S. Aslan, L. Thomas, J. Mould, R. Drinkwater, M. D. Baker, B. Abrahamsen, J. N. Wood, et al.
{micro}O-conotoxin MrVIB selectively blocks Nav1.8 sensory neuron specific sodium channels and chronic pain behavior without motor deficits
PNAS, November 7, 2006; 103(45): 17030 - 17035.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
A. M. Strassman and D. Levy
Response Properties of Dural Nociceptors in Relation to Headache
J Neurophysiol, March 1, 2006; 95(3): 1298 - 1306.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
M. D Baker
Protein kinase C mediates up-regulation of tetrodotoxin-resistant, persistent Na+ current in rat and mouse sensory neurones
J. Physiol., September 15, 2005; 567(3): 851 - 867.
[Abstract] [Full Text] [PDF]

Home page
 J. Pharmacol. Exp. Ther.Home page
S. Yoshida and S. Matsumoto
Effects of {alpha}-Dendrotoxin on K+ Currents and Action Potentials in Tetrodotoxin-Resistant Adult Rat Trigeminal Ganglion Neurons
J. Pharmacol. Exp. Ther., July 1, 2005; 314(1): 437 - 445.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
D. Levy and A. M. Strassman
Modulation of Dural Nociceptor Mechanosensitivity by the Nitric Oxide-Cyclic GMP Signaling Cascade
J Neurophysiol, August 1, 2004; 92(2): 766 - 772.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
D. Levy and A. M. Strassman
Mechanical Response Properties of A and C Primary Afferent Neurons Innervating the Rat Intracranial Dura
J Neurophysiol, December 1, 2002; 88(6): 3021 - 3031.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurosci.Home page
N. T. Blair and B. P. Bean
Roles of Tetrodotoxin (TTX)-Sensitive Na+ Current, TTX-Resistant Na+ Current, and Ca2+ Current in the Action Potentials of Nociceptive Sensory Neurons
J. Neurosci., December 1, 2002; 22(23): 10277 - 10290.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
A. Grigaliunas, R. M. Bradley, D. K. MacCallum, and C. M. Mistretta
Distinctive Neurophysiological Properties of Embryonic Trigeminal and Geniculate Neurons in Culture
J Neurophysiol, October 1, 2002; 88(4): 2058 - 2074.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
M. S. Gold, L. Zhang, D. L. Wrigley, and R. J. Traub
Prostaglandin E2 Modulates TTX-R INa in Rat Colonic Sensory Neurons
J Neurophysiol, September 1, 2002; 88(3): 1512 - 1522.
[Abstract] [Full Text] [PDF]

Home page
 JGPHome page
R. W. Carr, S. Pianova, and J. A. Brock
The Effects of Polarizing Current on Nerve Terminal Impulses Recorded from Polymodal and Cold Receptors in the Guinea-pig Cornea
J. Gen. Physiol., August 26, 2002; 120(3): 395 - 405.
[Abstract] [Full Text] [PDF]

Home page
 Br J AnaesthHome page
A. Scholz
Mechanisms of (local) anaesthetics on voltage-gated sodium and other ion channels
Br. J. Anaesth., July 1, 2002; 89(1): 52 - 61.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
D. Levy and A. M. Strassman
Distinct sensitizing effects of the cAMP-PKA second messenger cascade on rat dural mechanonociceptors
J. Physiol., January 9, 2002; 538(2): 483 - 493.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online