Pathway
Acetylcholine inhibits contraction of outer hair cells
Outer hair cells (OHCs) are synapsed with efferent cholinergic medial olivocochlear fibers (reviewed in Fritzsch and Elliott 2017, Fuchs and Lauer 2019). Acetylcholine released at the synapse binds an unusual, nicotine-antagonized, nicotinic receptor comprising CHRNA9 and CHRNA10. Upon binding acetylcholine, CHRNA9:CHRNA10 transports calcium ions into the OHC. The calcium activates nearby SK2 potassium channels (KCNN2, small potassium current channels) and BK potassium channels (KCNMA1:KCNMB1, big potassium current channels) which extrude potassium ions, hyperpolarize the OHC, and inhibit activation of the OHC.
Continue reading
The overall effects of acetylcholine on OHCs are complex. OHCs exhibit fast motility caused by voltage effect on SLC26A5 and slow motility caused by cytoskeleton organization.
What the reference databases state
Statements
5 statements
5 statements · 1 reference database · Subject: Acetylcholine inhibits contraction of outer hair cells · Sources: Reactome
- CHRNA10 participates in Acetylcholine inhibits contraction of outer hair cellsProteinReactome R-HSA-9667769Inferred only
- CHRNA9 participates in Acetylcholine inhibits contraction of outer hair cellsProteinReactome R-HSA-9667769Inferred only
- KCNMA1 participates in Acetylcholine inhibits contraction of outer hair cellsProteinReactome R-HSA-9667769Inferred only
- KCNMB1 participates in Acetylcholine inhibits contraction of outer hair cellsProteinReactome R-HSA-9667769Inferred only
- KCNN2 participates in Acetylcholine inhibits contraction of outer hair cellsProteinReactome R-HSA-9667769Inferred only