MECHANOELECTRICAL TRANSDUCER CURRENTS IN HAIR-CELLS OF THE CULTURED NEONATAL MOUSE COCHLEA
MECHANOELECTRICAL TRANSDUCER CURRENTS IN HAIR-CELLS OF THE CULTURED NEONATAL MOUSE COCHLEA
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DOI：
10.1098/rspb.1992.0102
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发表时间：
1992-08-22
影响因子：
4.7
通讯作者：
RICHARDSON, GP
中科院分区：
文献类型：
--
作者：
KROS, CJ;RUSCH, A;RICHARDSON, GP
在毛细胞中产生受体电位的第一步是通过静纤毛的偏转诱导换能器通道的门控和随后的换能器电流的流动。我们描述了新生小鼠外毛细胞的换能器电流的特性。对内毛细胞的不太广泛的观察表明，它们的换能器电流具有类似的特征。毛束受到来自流体喷射的力的刺激。外毛细胞中的传感器电流是迄今为止在任何毛细胞中发现的最大的，在-84 mV下的弦电导高达9.2 nS。传递函数表明通道至少有两个闭合状态和一个打开状态。钠、钾和铯的渗透性相似，与通道是相当非选择性的阳离子通道一致。在负电位下，电流在大多数细胞中适应，尽管从未像低等脊椎动物的毛细胞那样完全适应。如果换能器通道的单位电导与海龟的听毛细胞的单位电导相似（100 pS），那么每个毛束大约有90个通道，或者相邻行中每对相邻静纤毛之间有一个通道。
The first step towards the generation of the receptor potential in hair cells is the gating of the transducer channels and subsequent flow of transducer current, induced by deflection of the stereocilia. We describe properties of the transducer current in outer hair cells of neonatal mice. Less extensive observations on inner hair cells suggest that their transducer currents have similar characteristics. The hair bundles were stimulated by force from a fluid jet. The transducer currents in outer hair cells are the largest found so far in any hair cell, with a chord conductance of up to 9.2 nS at -84 mV. The transfer function suggests that the channel has at least two closed states and one open state. The permeabilities for sodium, potassium and caesium are similar, consistent with the channel being a fairly non-selective cation channel. At negative potentials the currents adapt in most cells, although never as completely as in hair cells of lower vertebrates. If the unit conductance of the transducer channel is similar to that of the turtle's auditory hair cells (100 pS), then there are about 90 channels per hair bundle, or one channel between every pair of adjacent stereocilia in neighbouring rows.