Neuronal acetylcholine receptor subunit alpha-9 (CHRNA9)

Ionotropic receptor with a probable role in the modulation of auditory stimuli. Agonist binding induces a conformation change that contributes to the opening of an ion-conducting channel across the plasma membrane (PubMed:11752216, PubMed:25282151).

The channel is permeable to a range of divalent cations such as calcium, the influx of which may activate a potassium current which hyperpolarizes the cell membrane (PubMed:11752216, PubMed:25282151). In the ear, this can result in a reduction in basilar membrane motion, altering the activity of auditory nerve fibers and reducing the range of dynamic hearing.