HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Free Full Text (PDF) Free All Versions of this Article: 98/2/526    most recent 00970.2004v1 Submit a response Alert me when this article is cited Alert me when eLetters are posted 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 (8) Citing Articles via Google Scholar Google Scholar Articles by Mori, R. L. Articles by Yates, B. J. Search for Related Content PubMed PubMed Citation Articles by Mori, R. L. Articles by Yates, B. J.

Effects of bilateral vestibular nucleus lesions on cardiovascular regulation in conscious cats

Departments of Otolaryngology and Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania

Submitted 3 September 2004 ; accepted in final form 6 October 2004

The vestibular system participates in cardiovascular regulation during postural changes. In prior studies (Holmes MJ, Cotter LA, Arendt HE, Cas SP, and Yates BJ. Brain Res 938: 62–72, 2002, and Jian BJ, Cotter LA, Emanuel BA, Cass SP, and Yates BJ. J Appl Physiol 86: 1552–1560, 1999), transection of the vestibular nerves resulted in instability in blood pressure during nose-up body tilts, particularly when no visual information reflecting body position in space was available. However, recovery of orthostatic tolerance occurred within 1 wk, presumably because the vestibular nuclei integrate a variety of sensory inputs reflecting body location. The present study tested the hypothesis that lesions of the vestibular nuclei result in persistent cardiovascular deficits during orthostatic challenges. Blood pressure and heart rate were monitored in five conscious cats during nose-up tilts of varying amplitude, both before and after chemical lesions of the vestibular nuclei. Before lesions, blood pressure remained relatively stable during tilts. In all animals, the blood pressure responses to nose-up tilts were altered by damage to the medial and inferior vestibular nuclei; these effects were noted both when animals were tested in the presence and absence of visual feedback. In four of the five animals, the lesions also resulted in augmented heart rate increases from baseline values during 60° nose-up tilts. These effects persisted for longer than 1 wk, but they gradually resolved over time, except in the animal with the worst deficits. These observations suggest that recovery of compensatory cardiovascular responses after loss of vestibular inputs is accomplished at least in part through plastic changes in the vestibular nuclei and the enhancement of the ability of vestibular nucleus neurons to discriminate body position in space by employing nonlabyrinthine signals.

vestibular system; excitotoxicity; compensation; multisensory integration

This article has been cited by other articles:

				H. Zhu, J. R. Jordan, S. P. G. Hardy, B. Fulcher, C. Childress, C. Varner, B. Windham, B. Jeffcoat, R. W. Rockhold, and W. Zhou Linear acceleration-evoked cardiovascular responses in awake rats J Appl Physiol, August 1, 2007; 103(2): 646 - 654. [Abstract] [Full Text] [PDF]

				T. D. Wilson, L. A. Cotter, J. A. Draper, S. P. Misra, C. D. Rice, S. P. Cass, and B. J. Yates Vestibular inputs elicit patterned changes in limb blood flow in conscious cats J. Physiol., September 1, 2006; 575(2): 671 - 684. [Abstract] [Full Text] [PDF]

				T. D. Wilson, L. A. Cotter, J. A. Draper, S. P. Misra, C. D. Rice, S. P. Cass, and B. J. Yates Effects of postural changes and removal of vestibular inputs on blood flow to the head of conscious felines J Appl Physiol, May 1, 2006; 100(5): 1475 - 1482. [Abstract] [Full Text] [PDF]