豚鼠耳蜗孤立外毛细胞中的钙通道。

Calcium channel in isolated outer hair cells of guinea pig cochlea.

作者信息

Nakagawa T, Kakehata S, Akaike N, Komune S, Takasaka T, Uemura T

机构信息

Department of Neurophysiology, Tohoku University School of Medicine, Sendai, Japan.

出版信息

Neurosci Lett. 1991 Apr 15;125(1):81-4. doi: 10.1016/0304-3940(91)90136-h.

DOI:10.1016/0304-3940(91)90136-h

PMID:1649986

Abstract

The physiological and pharmacological properties of the Ca2+ channel in outer hair cells (OHCs) freshly isolated from guinea pig cochlea were investigated using a whole-cell patch-clamp technique. The Ca2+ current (ICa) was activated from a membrane potential of -20 mV and reached peak value around +20 mV in external solution containing 20 mM Ca2+ at a holding potential of -70 mV. The peak amplitude of ICa increased in a hyperbolic manner with increasing extracellular Ca2+ concentration. The ion selectively was Ba2+ much greater than Ca2+ greater than or equal to Sr2+. It was concluded that the Ca2+ channel in OHCs of guinea pig is of the L-type.

摘要

采用全细胞膜片钳技术，研究了从豚鼠耳蜗新鲜分离的外毛细胞（OHCs）中Ca2+通道的生理和药理特性。在含有20 mM Ca2+的细胞外溶液中，于-70 mV的钳制电位下，Ca2+电流（ICa）从-20 mV的膜电位开始激活，并在+20 mV左右达到峰值。ICa的峰值幅度随细胞外Ca2+浓度的增加呈双曲线方式增加。离子选择性为Ba2+远大于Ca2+大于或等于Sr2+。得出结论，豚鼠OHCs中的Ca2+通道为L型。