Yamasaki M, Komune S, Shimozono M, Matsuda K, Haruta A
Department of Otolaryngology, Miyazaki Medical College, Miyazaki, Japan.
ORL J Otorhinolaryngol Relat Spec. 2000 Sep-Oct;62(5):241-6. doi: 10.1159/000027753.
The present study was designed to clarify the chronological developmental process of monovalent ions (Na(+), K(+), Cl(-)) in the endolymph of the mouse in relation to the development of the endocochlear potential (EP). The EP and ionic concentrations were measured simultaneously with the ion-sensitive double-barreled microelectrodes from the scala media of the basal turn. The EP increased abruptly 7 days after birth (DAB) and reached approximately 80 mV 14 DAB. In the earliest postnatal days, the endolymphatic Na(+) concentration was significantly higher than that in adult mice, however, the K(+) and the Cl(-) concentrations were lower. The concentrations of all the monovalent ions in endolymph reached adult levels at 7 DAB when the EP was still under 20 mV. These data strongly suggest the presence of a different mechanism between the production of monovalent ions, especially of high K(+) in the endolymph and that of EP.
本研究旨在阐明小鼠内淋巴中单价离子（Na⁺、K⁺、Cl⁻）的时间发育过程与内耳蜗电位（EP）发育的关系。使用离子敏感双管微电极从蜗底中阶同时测量EP和离子浓度。出生后7天（DAB）EP突然升高，出生后14天达到约80 mV。在出生后的最初几天，内淋巴中Na⁺浓度显著高于成年小鼠，然而，K⁺和Cl⁻浓度较低。当EP仍低于20 mV时，内淋巴中所有单价离子的浓度在出生后7天达到成年水平。这些数据有力地表明，内淋巴中单价离子尤其是高K⁺的产生与EP的产生之间存在不同的机制。
