Elgoyhen A B, Johnson D S, Boulter J, Vetter D E, Heinemann S
Salk Institute for Biological Studies, La Jolla, California 92037.
Cell. 1994 Nov 18;79(4):705-15. doi: 10.1016/0092-8674(94)90555-x.
We report the isolation and functional characterization of a member of the nicotinic acetylcholine receptor subunit gene family, alpha 9. Xenopus oocytes injected with alpha 9 cRNA express a homomeric receptor-channel complex that is activated by acetylcholine. The alpha 9 receptor displays an unusual mixed nicotinic-muscarinic pharmacological profile. The unique properties of the alpha 9 receptor-channel complex closely match those described for the cholinergic receptor present in vertebrate cochlear hair cells. In situ hybridization studies reveal a restricted pattern of alpha 9 gene expression that includes the outer hair cells of the rat cochlea. Our results suggest that the alpha 9 receptor is involved in the cholinergic efferent innervation of cochlear hair cells and thus may modulate the encoding of auditory stimuli.
我们报告了烟碱型乙酰胆碱受体亚基基因家族成员α9的分离及功能特性。注射α9互补RNA（cRNA）的非洲爪蟾卵母细胞表达一种由乙酰胆碱激活的同聚受体-通道复合物。α9受体呈现出一种不寻常的混合型烟碱-毒蕈碱药理学特征。α9受体-通道复合物的独特特性与脊椎动物耳蜗毛细胞中存在的胆碱能受体所描述的特性非常匹配。原位杂交研究揭示了α9基因表达的局限性模式，包括大鼠耳蜗的外毛细胞。我们的结果表明，α9受体参与耳蜗毛细胞的胆碱能传出神经支配，因此可能调节听觉刺激的编码。
