Effects of betahistine on the spatiotemporal response properties of vestibulospinal neurons to labyrinthine volleys
European Journal of Pharmacology. 2005-05-01; 515(1-3): 73-82
DOI: 10.1016/j.ejphar.2005.03.043
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1. Eur J Pharmacol. 2005 May 16;515(1-3):73-82.
Effects of betahistine on the spatiotemporal response properties of
vestibulospinal neurons to labyrinthine volleys.
Barresi M(1), Bruschini L, Li Volsi G, Manzoni D.
Author information:
(1)Dipartimento di Scienze Fisiologiche, Università di Catania, Viale A. Doria 6,
I-95125 Catania, Italy.
Betahistine, a drug used in the treatment of vestibular disorders, speeds-up the
recovery from hemilabyrinthectomy in experimental animals, likely through the
activation of histamine receptors. In order to better understand the mechanism of
action of this drug we investigated, in adult, urethane anesthetized rats,
whether betahistine modifies the spatial (directional) and temporal response
properties of vestibular nuclear neurons to the labyrinthine input, as well as
the convergence of different labyrinthine signals on single units. Extracellular
single-unit activity was recorded from the caudal, spinal-projecting region of
the vestibular nuclei during tilt of the animal, before and after i.p. injection
of betahistine. The two orthogonal directions of maximal and minimal response to
tilt, as well as the corresponding gains were determined for each neuron.
Betahistine reduced the maximal response gain of units showing larger basal
values of this parameter and increased it in neurons with smaller basal values,
while the minimal response gain was on the average raised. These changes led to a
significant decrease in the spatial specificity of the neurons, suggesting that
betahistine affects the process of spatiotemporal convergence on vestibular
units, likely through a rearrangement of the various inputs. This could be
related to the effect of the drug on vestibular compensation.
DOI: 10.1016/j.ejphar.2005.03.043
PMID: 15878499 [Indexed for MEDLINE]