Journal of Neurophysiology, Vol 39, Issue 5 936-953, Copyright © 1976 by APS

ARTICLES

Trigeminothalamic neurons in nucleus caudalis responsive to tactile, thermal, and nociceptive stimulation of monkey's face

D. D. Price, R. Dubner and J. W. Hu

1. A total of 113 trigeminothalamic neurons and over 200 presumed interneurons of nucleus caudalis (0-5 mm below the obex) and subjacent reticular formation were studied in rhesus monkeys anesthetized with chloralose or nitrous oxide. Each cell was characterized in terms of its antidromic responses to stimulation of ventral posterior medial and/or posterior thalamic nuclei and to three types of stimuli applied to its receptive field: a) graded 5-s temperature shifts at a rate of 9 degrees C/s from 35 degrees C to final temperatures of 20-52 degrees C, generated by a contact thermode; b) graded intensities of electrical stimulation to determine the conduction velocities of converging primary afferent fiber populations; and c) mechanical stimulation ranging from light touch to pinch with serrated forceps. 2. This analysis yielded five classes of units distinguished by the range of responses to mechanical stimuli and by the convergence of different primary afferent fiber populations. These five classes were found among both trigeminothalamic neurons and neurons which could not be antidromically activated. Class 1 units exhibited rapidly adapting responses to hair movement or light touch and received only A-beta primary afferent input. Class 2 units responded to light touch and pressure with maintained discharges and received A-beta primary afferent input. Class 3 units responded maximally to pinch with serrated forceps but also were activated by light touch and pressure. They received A-beta, A-delta, and C fiber input. Class 4 units responded to firm pressure and maximally to pinch with serrated forceps. These units had A-delta and sometimes C fiber input. Class 5 units responded only to pinch with serrated forceps and had exclusive A-delta fiber input. Some cells in all five classes responded antidromically to stimulation of the thalamus. Antidromic action-potential latencies of classes 1,2, and 3 units were shorter than those of classes 4 and 5 units (P less than 0.001). Receptive-field sizes were usually small (1-2 cm2) for classes 1, 2, 4, and 5 units, and larger for class 3 units (one to three trigeminal divisions). The marginal layer of nucleus caudalis contained mostly classes 4 and 5 units, some class 3 units, but no classes 1 or 2 units. The superficial portion of the magnocellular layer contained mostly classes 1 and 2 units, while neurons at the base of this layer contained class 3 units and some classes 4 and 5 units. Cells in the sujacent reticular formation included all 5 classes but showed a tendency to have large receptive fields (greater than 1 trigeminal division). 3. Neurons responding to noxious thermal stimuli (44-52 degrees C) were classes 3 or 4 units. The response patterns of classes 3 and 4 units to noxious thermal stimuli were similar. No classes 1 or 2 units and only one class 5 unit responded to increases in skin temperature. Thermal thresholds ranged from 38 to 50 degrees C and most heat-responsive units responded monotonically to temperatures between 45 and 52 degrees C...

This article has been cited by other articles:

				K. Saito, S. Hitomi, I. Suzuki, Y. Masuda, J. Kitagawa, Y. Tsuboi, M. Kondo, B. J. Sessle, and K. Iwata Modulation of Trigeminal Spinal Subnucleus Caudalis Neuronal Activity Following Regeneration of Transected Inferior Alveolar Nerve in Rats J Neurophysiol, May 1, 2008; 99(5): 2251 - 2263. [Abstract] [Full Text] [PDF]

				K. Kubo, Y. Shibukawa, M. Shintani, T. Suzuki, T. Ichinohe, and Y. Kaneko Cortical Representation Area of Human Dental Pulp J. Dent. Res., April 1, 2008; 87(4): 358 - 362. [Abstract] [Full Text] [PDF]

				G. Cruccu, G. D. Iannetti, J. J. Marx, F. Thoemke, A. Truini, S. Fitzek, F. Galeotti, P. P. Urban, A. Romaniello, P. Stoeter, et al. Brainstem reflex circuits revisited Brain, February 1, 2005; 128(2): 386 - 394. [Abstract] [Full Text] [PDF]

				A. Graziano and E. G. Jones Widespread Thalamic Terminations of Fibers Arising in the Superficial Medullary Dorsal Horn of Monkeys and Their Relation to Calbindin Immunoreactivity J. Neurosci., January 7, 2004; 24(1): 248 - 256. [Abstract] [Full Text] [PDF]

				A. Woda Pain in the Trigeminal System: from Orofacial Nociception to Neural Network Modeling J. Dent. Res., October 1, 2003; 82(10): 764 - 768. [Full Text] [PDF]

				G.D. Iannetti, A. Truini, A. Romaniello, F. Galeotti, C. Rizzo, M. Manfredi, and G. Cruccu Evidence of a Specific Spinal Pathway for the Sense of Warmth in Humans J Neurophysiol, January 1, 2003; 89(1): 562 - 570. [Abstract] [Full Text] [PDF]

				B. Hu, C. Y. Chiang, J. W. Hu, J. O. Dostrovsky, and B. J. Sessle P2X Receptors in Trigeminal Subnucleus Caudalis Modulate Central Sensitization in Trigeminal Subnucleus Oralis J Neurophysiol, October 1, 2002; 88(4): 1614 - 1624. [Abstract] [Full Text] [PDF]

				D. D. Price Central Neural Mechanisms that Interrelate Sensory and Affective Dimensions of Pain Mol. Interv., October 1, 2002; 2(6): 392 - 403. [Abstract] [Full Text] [PDF]

				A. F. M. DaSilva, L. Becerra, N. Makris, A. M. Strassman, R. G. Gonzalez, N. Geatrakis, and D. Borsook Somatotopic Activation in the Human Trigeminal Pain Pathway J. Neurosci., September 15, 2002; 22(18): 8183 - 8192. [Abstract] [Full Text] [PDF]

				D. Andrew and A. D. Craig Responses of Spinothalamic Lamina I Neurons to Maintained Noxious Mechanical Stimulation in the Cat J Neurophysiol, April 1, 2002; 87(4): 1889 - 1901. [Abstract] [Full Text] [PDF]

				A. Romaniello, J. Valls-Sole, G. D. Iannetti, A. Truini, M. Manfredi, and G. Cruccu Nociceptive Quality of the Laser-Evoked Blink Reflex in Humans J Neurophysiol, March 1, 2002; 87(3): 1386 - 1394. [Abstract] [Full Text] [PDF]

				D. J. Kelly, M. Ahmad, and S. J. Brull Preemptive analgesia I: physiological pathways and pharmacological modalities : [L'analgesie preventive I : mecanismes physiologiques et modalites pharmacologiques] Can J Anesth, November 1, 2001; 48(10): 1000 - 1010. [Abstract] [Full Text] [PDF]

				A. D. Craig, K. Krout, and D. Andrew Quantitative Response Characteristics of Thermoreceptive and Nociceptive Lamina I Spinothalamic Neurons in the Cat J Neurophysiol, September 1, 2001; 86(3): 1459 - 1480. [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]

				H. Bester, V. Chapman, J.-M. Besson, and J.-F. Bernard Physiological Properties of the Lamina I Spinoparabrachial Neurons in the Rat J Neurophysiol, April 1, 2000; 83(4): 2239 - 2259. [Abstract] [Full Text] [PDF]

				K. Iwata, A. Tashiro, Y. Tsuboi, T. Imai, R. Sumino, T. Morimoto, R. Dubner, and K. Ren Medullary Dorsal Horn Neuronal Activity in Rats with Persistent Temporomandibular Joint and Perioral Inflammation J Neurophysiol, September 1, 1999; 82(3): 1244 - 1253. [Abstract] [Full Text] [PDF]

				E. Carstens, N. Kuenzler, and H. O. Handwerker Activation of Neurons in Rat Trigeminal Subnucleus Caudalis by Different Irritant Chemicals Applied to Oral or Ocular Mucosa J Neurophysiol, August 1, 1998; 80(2): 465 - 492. [Abstract] [Full Text] [PDF]

				W. D. Hutchison, J. Tsoukatos, and J. O. Dostrovsky Quantitative Analysis of Orofacial Thermoreceptive Neurons in the Superficial Medullary Dorsal Horn of the Rat J Neurophysiol, June 1, 1997; 77(6): 3252 - 3266. [Abstract] [Full Text] [PDF]

				I. D. Meng, J. W. Hu, A. P. Benetti, and D. A. Bereiter Encoding of Corneal Input in Two Distinct Regions of the Spinal Trigeminal Nucleus in the Rat: Cutaneous Receptive Field Properties, Responses to Thermal and Chemical Stimulation, Modulation by Diffuse Noxious Inhibitory Controls, and Projections to the Parabrachial Area J Neurophysiol, January 1, 1997; 77(1): 43 - 56. [Abstract] [Full Text] [PDF]

				B. E. Cairns, S. A. McErlane, M. C. Fragoso, W. G. Jia, and P. J. Soja Spontaneous Discharge and Peripherally Evoked Orofacial Responses of Trigemino-Thalamic Tract Neurons during Wakefulness and Sleep J. Neurosci., December 15, 1996; 16(24): 8149 - 8159. [Abstract] [Full Text] [PDF]

				K. Casey and T. Morrow Ventral posterior thalamic neurons differentially responsive to noxious stimulation of the awake monkey Science, August 12, 1983; 221(4611): 675 - 677. [Abstract] [PDF]

				M. Ruda Opiates and pain pathways: demonstration of enkephalin synapses on dorsal horn projection neurons Science, March 19, 1982; 215(4539): 1523 - 1525. [Abstract] [PDF]