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: 92/3/1668    most recent 00158.2004v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science 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 ISI Web of Science (14) Citing Articles via Google Scholar Google Scholar Articles by Beraneck, M. Articles by Vibert, N. Search for Related Content PubMed PubMed Citation Articles by Beraneck, M. Articles by Vibert, N.

Unilateral Labyrinthectomy Modifies the Membrane Properties of Contralesional Vestibular Neurons

Laboratoire de Neurobiologie des Réseaux Sensorimoteurs, Centre National de la Recherche Scientifique-Université Paris 5, Unite Mixte de Recherche 7060, 75270 Paris Cédex 06, France

Submitted 18 February 2004; accepted in final form 10 May 2004

Vestibular compensation after a unilateral labyrinthectomy leads to nearly complete disappearance of the static symptoms triggered by the lesion. However, the dynamic vestibular reflexes associated with head movements remain impaired. Because the contralesional labyrinth plays a prominent role in the generation of these dynamic responses, intracellular recordings of contralesional medial vestibular nucleus neurons (MVNn) were done after 1 mo of compensation. Their firing properties and cell type were characterized at rest, and their response dynamics investigated using step, ramp, and sinusoidal current stimulations. The sensitivity of the contralesional MVNn firing rates to applied current was increased, which, along with increased phase leads, suggests that significant changes in active conductances occurred. We found an increased proportion of the phasic type B neurons relative to the tonic type A neurons in the contralesional MVN. In addition, the remaining contralesional type A MVNn response dynamics tended to approach those of type B MVNn. Thus the contralesional MVNn in general showed more phasic response dynamics than those of control MVNn. Altogether, the firing properties of MVNn are differentially modified on the ipsilesional and contralesional sides of the brain stem 1 mo after unilateral labyrinthectomy. Ipsilesional MVNn acquire more "type A–like" tonic membrane properties, which would contribute to the stabilization of the spontaneous activity that recovers in the deafferented neurons during vestibular compensation. The bilateral increase in the sensitivity of MVNn and the acquisition of more "B-like" phasic membrane properties by contralesional MVNn should promote the restoration of the vestibular reflexes generated by the remaining, contralesional labyrinth.

This article has been cited by other articles:

				F. Bergquist, M. Ludwig, and M. B. Dutia Role of the commissural inhibitory system in vestibular compensation in the rat J. Physiol., September 15, 2008; 586(18): 4441 - 4452. [Abstract] [Full Text] [PDF]

				M. Beraneck, J. L. McKee, M. Aleisa, and K. E. Cullen Asymmetric Recovery in Cerebellar-Deficient Mice Following Unilateral Labyrinthectomy J Neurophysiol, August 1, 2008; 100(2): 945 - 958. [Abstract] [Full Text] [PDF]

				D. Eugene, S. Deforges, F. Guimont, E. Idoux, P.-P. Vidal, L. E. Moore, and N. Vibert Developmental regulation of the membrane properties of central vestibular neurons by sensory vestibular information in the mouse J. Physiol., September 15, 2007; 583(3): 923 - 943. [Abstract] [Full Text] [PDF]

				A. H. Gittis and S. du Lac Firing Properties of GABAergic Versus Non-GABAergic Vestibular Nucleus Neurons Conferred by a Differential Balance of Potassium Currents J Neurophysiol, June 1, 2007; 97(6): 3986 - 3996. [Abstract] [Full Text] [PDF]

				H. A. Raptis, E. Dannenbaum, N. Paquet, and A. G. Feldman Vestibular System May Provide Equivalent Motor Actions Regardless of the Number of Body Segments Involved in the Task J Neurophysiol, June 1, 2007; 97(6): 4069 - 4078. [Abstract] [Full Text] [PDF]

				M. W. Bagnall, R. J. Stevens, and S. du Lac Transgenic Mouse Lines Subdivide Medial Vestibular Nucleus Neurons into Discrete, Neurochemically Distinct Populations J. Neurosci., February 28, 2007; 27(9): 2318 - 2330. [Abstract] [Full Text] [PDF]

				S. G. Sadeghi, L. B. Minor, and K. E. Cullen Response of Vestibular-Nerve Afferents to Active and Passive Rotations Under Normal Conditions and After Unilateral Labyrinthectomy J Neurophysiol, February 1, 2007; 97(2): 1503 - 1514. [Abstract] [Full Text] [PDF]

				E. Idoux, M. Serafin, P. Fort, P.-P. Vidal, M. Beraneck, N. Vibert, M. Muhlethaler, and L. E. Moore Oscillatory and Intrinsic Membrane Properties of Guinea Pig Nucleus Prepositus Hypoglossi Neurons In Vitro J Neurophysiol, July 1, 2006; 96(1): 175 - 196. [Abstract] [Full Text] [PDF]