| First Author | Morley BJ | Year | 2017 |
| Journal | J Comp Neurol | Volume | 525 |
| Issue | 5 | Pages | 1216-1233 |
| PubMed ID | 27718229 | Mgi Jnum | J:241158 |
| Mgi Id | MGI:5897932 | Doi | 10.1002/cne.24131 |
| Citation | Morley BJ, et al. (2017) Nicotinic acetylcholine receptors regulate vestibular afferent gain and activation timing. J Comp Neurol 525(5):1216-1233 |
| abstractText | Little is known about the function of the cholinergic efferents innervating peripheral vestibular hair cells. We measured vestibular sensory evoked potentials (VsEPs) in alpha9 knockout (KO) mice, alpha10 KO mice, alpha7 KO mice, alpha9/10 and alpha7/9 double KO mice, and wild-type (WT) controls. We also studied the morphology and ultrastructure of efferent terminals on vestibular hair cells in alpha9, alpha10, and alpha9/10 KOs. Both type I and type ll vestibular hair cells express the alpha9 and alpha10 subunits. The efferent boutons on vestibular cells in alpha9, alpha10, and alpha9/10 KOs appeared normal, but a quantitative analysis was not performed. Mean VsEP thresholds were significantly elevated in alpha9 and alpha9/10 KO animals. Some alpha9 and alpha9/10 KO animals, however, had normal or near-normal thresholds, whereas others were greatly affected. Despite individual variability in threshold responses, latencies were consistently shortened. The double alpha7/9 KO resulted in decreased variance by normalizing waveforms and latencies. The phenotypes of the alpha7 and alpha10 single KOs were identical. Both alpha7 and alpha10 KO mice evidenced normal thresholds, decreased activation latencies, and larger amplitudes compared with WT mice. The data suggest a complex interaction of nicotinic acetylcholine receptors (nAChRs) in regulating vestibular afferent gain and activation timing. Although the alpha9/10 heteromeric nAChR is an important component of vestibular efferent activity, other peripheral or central nAChRs involving the alpha7 subunit or alpha10 subunit and alpha9 homomeric receptors are also important. J. Comp. Neurol. 525:1216-1233, 2017. (c) 2016 Wiley Periodicals, Inc. |
