Hisashi K, Komune S, Kimitsuki T, Nakagawa T, Uemura T
Department of Otorhinolaryngology, Faculty of Medicine, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812, Japan.
Eur Arch Otorhinolaryngol. 1994;251 Suppl 1:S48-52. doi: 10.1007/BF02565219.
To determine whether any differences exist in potassium circulation between the scala vestibuli and scala tympani, we recorded the change in K+ activity in both scalae of the guinea pig cochlea at the basal and third turns, using a double-barrelled, K(+)-sensitive microelectrode after perfusion with artificial perilymph containing 20 mM KCl and 130 mM NaCl. K+ activity increased immediately after the start of perfusion and decreased after its completion. The rates of decrease of K+ activities were approximately 1.0 mEq/l per min in the scala vestibuli of the basal and third turns, also 1.0 mEq/l per min in the scala tympani of the basal turn, and approximately 0.5 mEq/l per min in the scala tympani of the third turn. The rate of decrease of K+ activity in the scala tympani was significantly slower in the third turn than in the basal turn. Blockage of the cochlear aqueduct depressed the rate of decrease of K+ activity in the scala tympani more in the basal turn than in the third turn. These results suggest that there is a difference in potassium circulation between the scala vestibuli and scala tympani, and that the cochlear aqueduct plays an important role in potassium circulation in the perilymph of the scala tympani.
为了确定前庭阶和鼓阶之间的钾循环是否存在差异，我们在灌注含20 mM氯化钾和130 mM氯化钠的人工外淋巴后，使用双管钾敏感微电极记录了豚鼠耳蜗基底转和第三转的前庭阶和鼓阶中钾离子活性的变化。灌注开始后钾离子活性立即升高，灌注结束后降低。基底转和第三转前庭阶中钾离子活性的降低速率约为每分钟1.0 mEq/l，基底转鼓阶中也是每分钟1.0 mEq/l，第三转鼓阶中约为每分钟0.5 mEq/l。第三转鼓阶中钾离子活性的降低速率明显慢于基底转。阻塞蜗水管对基底转鼓阶中钾离子活性降低速率的抑制作用比对第三转的抑制作用更大。这些结果表明，前庭阶和鼓阶之间的钾循环存在差异，并且蜗水管在鼓阶外淋巴的钾循环中起重要作用。
