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Effer/Affer Interaction in Vestibular Caliceal vs. Dimorphic and Bouton Primary Afferent Neurons

ABSTRACT: The functional diversity of neuropeptides and/or their receptors may provide a complex means to modulate vestibular primary afferent neuronal function. The precise role of these neuropeptides in the physiology of the vestibular neuroepithelium is poorly understood. The vestibular caliceal afferent neurons when compared to the dimorphic and bouton afferent neurons have different functional properties. Immunofluorescent laser capture microdissection utilizing calretinin (calbindin 2, Calb2) antibodies allowed selective acquisition of these two primary afferent neuronal populations from the rat (Rattus norvegicus). After capturing the caliceal afferent neurons, as well as the dimorphic and bouton afferent neurons, microarray expression profiling was completed. Analysis of the resulting data revealed that there were 732 genes involved in synaptic/signaling, calcium binding/solute transport, and other. Of those genes, 52 were related to afferent modulation, including 21 genes representing neuropeptides or their receptors. The observed expression of 52 genes related to afferent modulation identified using microarray were confirmed using PCR from the Wackym-Soares normalized rat vestibular periphery cDNA library or by RT-PCR from fresh ganglia tissue. The majority of the neuropeptides and/or receptors were found to be expressed in both groups, although there were neuropeptides and/or receptors that were unique to the dimorphic and bouton afferent neuron pool. The expression of selected neuropeptides or their receptors was confirmed using immunohistochemistry in the crista ampullares. Our results suggest that the unexpected neuropeptide diversity and their differences in expression pattern could serve unique roles in the physiology of the vestibular neuroepithelium. Keywords: expression profiling, neuropeptides, vestibular neuroepithelium, calretinin

ORGANISM(S): Rattus norvegicus

PROVIDER: GSE4458 | GEO | 2006/04/01

SECONDARY ACCESSION(S): PRJNA94695

REPOSITORIES: GEO

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Effer/Affer Interaction in Vestibular Caliceal vs. Dimorphic and Bouton Primary Afferent Neurons

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