Ohmori H
National Institute for Physiological Sciences, Okazaki, Japan.
Jpn J Physiol. 1989;39(5):643-57. doi: 10.2170/jjphysiol.39.643.
Auditory and vestibular inputs are applied to the hair cell hair bundle as mechanical energy, and are transduced into electrical energy by gating ion channels, most likely at the base of the hair bundle. The mechano-electrical transduction channel has a unitary conductance of 50 pS and has a broad selectivity to monovalent cations and to divalent cations. Ca ions are the most permeable through the channel. The angular displacement of the hair bundle is the primary gating factor. However, we still do not know the exact linkage between the angular displacement and the channel gating. Circumstantial evidence indicates a possibility of the direct gating of channels by the membrane deformation itself. ATP and cholinergic muscarinic receptors likely mediate the inhibitory efferent innervation to the hair cell.
听觉和前庭传入信号作为机械能作用于毛细胞的毛束，并通过离子通道门控转换为电能，最有可能是在毛束基部。机械电转导通道的单通道电导为50 pS，对单价阳离子和二价阳离子具有广泛的选择性。钙离子是通过该通道最易通透的离子。毛束的角位移是主要的门控因素。然而，我们仍然不知道角位移与通道门控之间的确切联系。间接证据表明存在膜变形本身直接门控通道的可能性。ATP和胆碱能毒蕈碱受体可能介导对毛细胞的抑制性传出神经支配。
