EXPRESSION OF ALPHA-4 AND BETA-2 NICOTINIC ACETYLCHOLINE-RECEPTOR SUBUNIT MESSENGER-RNA AND LOCALIZATION OF ALPHA-BUNGAROTOXIN BINDING-PROTEINS IN THE RAT VESTIBULAR PERIPHERY
Pa. Wackym et al., EXPRESSION OF ALPHA-4 AND BETA-2 NICOTINIC ACETYLCHOLINE-RECEPTOR SUBUNIT MESSENGER-RNA AND LOCALIZATION OF ALPHA-BUNGAROTOXIN BINDING-PROTEINS IN THE RAT VESTIBULAR PERIPHERY, Cell biology international, 19(4), 1995, pp. 291-300
In situ hybridization histochemistry was used to map the distribution
of alpha 2, alpha 3, alpha 4, and beta 2 nAChR subunit mRNAs throughou
t the peripheral vestibular system of the rat. The alpha 4 and beta 2
nAChR subunit genes were co-expressed by populations of primary affere
nt neurons within Scarpa's ganglion, while there was no expression of
the alpha 2, alpha 3, alpha 4, or beta 2 nAChR subunit genes by type I
or type II vestibular hair cells. alpha-bungarotoxin binding to nAChR
s in the vestibular end-organs was primarily limited to the afferent c
halices surrounding type I hair cells and the basal aspect of type II
hair cells. These data suggest that nAChRs composed of alpha 4 and bet
a 2 subunits are localized on afferent chalices innervating the type I
vestibular hair cells and that the direct cholinergic efferent innerv
ation of the type II vestibular hair cells utilizes nAChR composed of
other subunits.