Journal of Neurophysiology, Vol 70, Issue 6 2370-2378, Copyright © 1993 by APS

ARTICLES

Neurons in the rat spinal trigeminal complex driven by corneal nociceptors: receptive-field properties and effects of noxious stimulation of the cornea

M. A. Pozo and F. Cervero
Department of Physiology, University of Bristol Medical School, University Walk, United Kingdom.

1. A survey of the receptive-field properties of neurons in the spinal trigeminal complex driven by stimulation of corneal afferents has been carried out. The afferent inputs to these neurons from the cornea and from the adjacent skin were studied as well as changes in the excitability of the cells and in the size of their receptive fields after thermal noxious stimulation of the cornea. 2. Single-unit electrophysiological recordings were made in pentobarbitone anesthetized rats from 54 neurons all of which were activated by mechanical stimulation of the ipsilateral cornea. Seventeen of these neurons were activated only by corneal stimulation and the other 37 had an additional cutaneous receptive field in the periorbital skin. Of the 37 neurons with a cutaneous receptive field, 29 were activated exclusively by noxious stimulation of the skin (Class 3) and the remaining 8 were driven by both innocuous and noxious cutaneous stimuli (Class 2). 3. All of the neurons were located in the ventro-lateral area of a region of the spinal trigeminal complex between +0.5 mm and -1.0 mm from the obex. This area corresponds to the most caudal part of subnucleus interpolaris, the transition zone between interpolaris and caudalis and the rostral half of subnucleus caudalis. Most neurons were located in the superficial layers of this part of the spinal trigeminal complex. No differences were observed between the locations of the recording sites of neurons with an exclusive corneal input and those with a corneal and a cutaneous receptive field.(ABSTRACT TRUNCATED AT 250 WORDS)

This article has been cited by other articles:

				Y. Feng and T. L. Simpson The Inhibitory Interaction between Human Corneal and Conjunctival Sensory Channels Invest. Ophthalmol. Vis. Sci., April 1, 2005; 46(4): 1251 - 1255. [Abstract] [Full Text] [PDF]

				A. Gruart, M. Streppel, O. Guntinas-Lichius, D. N. Angelov, W. F. Neiss, and J. M. Delgado-Garcia Motoneuron adaptability to new motor tasks following two types of facial-facial anastomosis in cats Brain, January 1, 2003; 126(1): 115 - 133. [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]

				C. T. Simons, J. -M. Dessirier, M. I. Carstens, M. O'Mahony, and E. Carstens Neurobiological and Psychophysical Mechanisms Underlying the Oral Sensation Produced by Carbonated Water J. Neurosci., September 15, 1999; 19(18): 8134 - 8144. [Abstract] [Full Text] [PDF]

				J. A. Trigo, A. Gruart, and J. M. Delgado-Garcia Discharge Profiles of Abducens, Accessory Abducens, and Orbicularis Oculi Motoneurons During Reflex and Conditioned Blinks in Alert Cats J Neurophysiol, April 1, 1999; 81(4): 1666 - 1684. [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]

				C. Roza, J. M. A. Laird, and F. Cervero Spinal Mechanisms Underlying Persistent Pain and Referred Hyperalgesia in Rats With an Experimental Ureteric Stone J Neurophysiol, April 1, 1998; 79(4): 1603 - 1612. [Abstract] [Full Text] [PDF]

				A. Ebersberger, M. Ringkamp, P. W. Reeh, and H. O. Handwerker Recordings From Brain Stem Neurons Responding to Chemical Stimulation of the Subarachnoid Space J Neurophysiol, June 1, 1997; 77(6): 3122 - 3133. [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]