| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
The Journal of Neurophysiology Vol. 80 No. 3 September 1998,
pp. 1082-1093
Copyright ©1998 The American Physiological Society
1 Department of Neurosurgery, School of Medicine, The Johns Hopkins University, Baltimore 21205; 2 Institute of Physiology and Pathophysiology, Johannes Gutenberg University, D-55099 Mainz, Germany; and 3 Applied Physics Laboratory, The Johns Hopkins University, Laurel, Maryland 20723
Treede, Rolf-Detlef, Richard A. Meyer, and James N. Campbell. Myelinated mechanically insensitive afferents from monkey hairy skin: heat-response properties. J. Neurophysiol. 80: 1082-1093, 1998. To compare the heat responses of mechanically sensitive and mechanically insensitive A-fiber nociceptors, an electrical search technique was used to locate the receptive fields of 156 A-fibers that innervated the hairy skin in the anesthetized monkey (77 A
-fibers, 79 A
-fibers). Two-thirds of these afferents were either low-threshold mechanoreceptors (n = 91) or low-threshold cold receptors (n = 11). Nine A-fibers and 41 A-fibers were cutaneous nociceptors, and four A-fibers innervated subcutaneous tissue. The majority of cutaneous A-fiber nociceptors were heat sensitive (43/50 = 86%). Heat-insensitive cutaneous A-fiber nociceptors consisted of one cold nociceptor, three silent nociceptors, and three high-threshold mechanoreceptors. Two types of response were observed to an intense heat stimulus (53°C, 30 s). Type I (n = 26) was characterized by a long latency (mean: 5 s) and a late peak discharge (16 s). Type II (n = 17) was characterized by a short latency (0.2 s) and an early peak discharge (0.5 s). Type I fibers exhibited faster conduction velocities (25 vs. 14 m/s) and higher heat thresholds (>53 vs. 47°C, 1-s duration) than type II fibers. The possibility that the type I heat response was a result of sensitization was tested in three fibers by determining the heat threshold to 30-s duration stimuli (42-46°C). For this long stimulus duration heat thresholds were reproducible across multiple runs, and the threshold to the 1-s duration stimulus was not altered by these tests. Thus fibers with a type I heat response were not high-threshold mechanoreceptors that developed a heat response through sensitization. Fibers with a type II heat response had significantly higher mechanical thresholds (median: 15 bar) than fibers with a type I heat response (5 bar). This finding accounts for the observation that type II heat responses were infrequently observed in earlier studies wherein the search technique depended on mechanical responsiveness. Fibers with a type II response exhibited a graded response to heat stimuli, marked fatigue to repeated applications of heat stimuli, and adaptation to sustained heat stimuli similar to that seen in C-fiber nociceptors. First pain sensation to heat is served by type II A-fiber nociceptors that are mechanically insensitive. Type I A-fiber nociceptors likely signal pain to long-duration heat stimuli and may signal first pain sensation to mechanical stimuli.
This article has been cited by other articles:
|
|
 |
|
  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]
|
|
|
|
 |
|
 G. D. Iannetti, L. Zambreanu, and I. Tracey Similar nociceptive afferents mediate psychophysical and electrophysiological responses to heat stimulation of glabrous and hairy skin in humans J. Physiol., November 15, 2006; 577(1): 235 - 248. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. McMullan and B. M. Lumb Spinal dorsal horn neuronal responses to myelinated versus unmyelinated heat nociceptors and their modulation by activation of the periaqueductal grey in the rat J. Physiol., October 15, 2006; 576(2): 547 - 556. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. N. Wenk, J.-D. Brederson, and C. N. Honda Morphine Directly Inhibits Nociceptors in Inflamed Skin J Neurophysiol, April 1, 2006; 95(4): 2083 - 2097. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. D. Iannetti, L. Zambreanu, R. G. Wise, T. J. Buchanan, J. P. Huggins, T. S. Smart, W. Vennart, and I. Tracey From The Cover: Pharmacological modulation of pain-related brain activity during normal and central sensitization states in humans PNAS, December 13, 2005; 102(50): 18195 - 18200. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. D. Iannetti and J.C.W. Brooks On the interpretation of temporal differences of BOLD fMRI responses to nociceptive stimulation J Neurophysiol, June 1, 2005; 93(6): 3718 - 3719. [Full Text] [PDF]
|
|
|
|
|
|
S. Ohara, N. E. Crone, N. Weiss, R.-D. Treede, and F. A. Lenz Cutaneous Painful Laser Stimuli Evoke Responses Recorded Directly From Primary Somatosensory Cortex in Awake Humans J Neurophysiol, June 1, 2004; 91(6): 2734 - 2746. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. M. Slugg, J. N. Campbell, and R. A. Meyer The Population Response of A- and C-Fiber Nociceptors in Monkey Encodes High-Intensity Mechanical Stimuli J. Neurosci., May 12, 2004; 24(19): 4649 - 4656. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Becerra, M. Iadarola, and D. Borsook CNS Activation by Noxious Heat to the Hand or Foot: Site-Dependent Delay in Sensory But Not Emotion Circuitry J Neurophysiol, January 1, 2004; 91(1): 533 - 541. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Ploner, H. Holthusen, P. Noetges, and A. Schnitzler Cortical Representation of Venous Nociception in Humans J Neurophysiol, July 1, 2002; 88(1): 300 - 305. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. Magerl, P. N. Fuchs, R. A. Meyer, and R.-D. Treede Roles of capsaicin-insensitive nociceptors in cutaneous pain and secondary hyperalgesia Brain, September 1, 2001; 124(9): 1754 - 1764. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Ringkamp, Y. B. Peng, G. Wu, T. V. Hartke, J. N. Campbell, and R. A. Meyer Capsaicin Responses in Heat-Sensitive and Heat-Insensitive A-Fiber Nociceptors J. Neurosci., June 15, 2001; 21(12): 4460 - 4468. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. C. Petruska, J. Napaporn, R. D. Johnson, J. G. Gu, and B. Y. Cooper Subclassified Acutely Dissociated Cells of Rat DRG: Histochemistry and Patterns of Capsaicin-, Proton-, and ATP-Activated Currents J Neurophysiol, November 1, 2000; 84(5): 2365 - 2379. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Malick, R. M. Strassman, and R. Burstein Trigeminohypothalamic and Reticulohypothalamic Tract Neurons in the Upper Cervical Spinal Cord and Caudal Medulla of the Rat J Neurophysiol, October 1, 2000; 84(4): 2078 - 2112. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. M. Slugg, R. A. Meyer, and J. N. Campbell Response of Cutaneous A- and C-Fiber Nociceptors in the Monkey to Controlled-Force Stimuli J Neurophysiol, April 1, 2000; 83(4): 2179 - 2191. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Kirschstein, W. Greffrath, D. Busselberg, and R.-D. Treede Inhibition of Rapid Heat Responses in Nociceptive Primary Sensory Neurons of Rats by Vanilloid Receptor Antagonists J Neurophysiol, December 1, 1999; 82(6): 2853 - 2860. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. A. Ziegler, W. Magerl, R. A. Meyer, and R.-D. Treede Secondary hyperalgesia to punctate mechanical stimuli: Central sensitization to A-fibre nociceptor input Brain, December 1, 1999; 122(12): 2245 - 2257. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
