title: Modulation by acute stress of chloride permeation across microdissected vestibular neurons membranes: different results in two rabbit strains and CRF involvement.
abstract: Free hand isolation of adult rabbit vestibular Deiters' neurons and dissection of their single membranes allows the study of their ionic permeability characteristics in a microchambers device. In the case of hare-like rabbits, the dissection of such membranes presents evidence of a high basal permeation of labelled chloride, possibly related to mechanical disturbance of the plasma membrane-related cytoskeleton and activation of chloride channels. This did not apply to the laboratory strain of white New Zealand rabbits. However, membranes from hare-like rabbits which were stressed by being rotated on a platform before the experiment, behaved like those from the New Zealand strain. Vice versa, habituation to handling day after day of New Zealand rabbits resulted in a chloride permeation equal to that of unstressed hare-like rabbits. We propose that the stressful conditions result in the release of neurochemical messages to the vestibular Deiters' cells which influence their electrophysiological behavior. The corticotropin releasing factor (CRF), a stress-related peptide present in the climbing fibers, actually blocks the basal chloride permeation across the Deiters' membranes and this effect is partially reversed by its receptor antagonist, alpha-helical CRF [9-41].
authors.affiliation: Centro di Neurofisiologia Cerebrale, C.N.R., Via De Toni, 5, 16132 Genoa, Italy.
authors.forename: M V
authors.initials: MV
authors.lastname: Rapallino
authors.forename: A
authors.initials: A
authors.lastname: Cupello
authors.forename: H
authors.initials: H
authors.lastname: Hydén
authors.forename: N L
authors.initials: NL
authors.lastname: Izvarina
mesh_terms: D000208:Acute Disease; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism*; D002463:Cell Membrane Permeability / Q000187:drug effects / Q000502:physiology*; D018118:Chloride Channels / Q000187:drug effects / Q000378:metabolism*; D003346:Corticotropin-Releasing Hormone / Q000187:drug effects / Q000378:metabolism*; D006185:Habituation, Psychophysiologic / Q000502:physiology; D008297:Male; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D011817:Rabbits; D013312:Stress, Physiological / Q000378:metabolism* / Q000503:physiopathology; D003689:Vestibular Nucleus, Lateral / Q000187:drug effects / Q000378:metabolism*
chemical_list: D018118:Chloride Channels; D003346:Corticotropin-Releasing Hormone