外淋巴钠、钾离子浓度对豚鼠蜗内电位的影响

The Effects of Potassium and Sodium in Perilymph on the Endocochlear Potential (EP) in Guinea Pig

用全耳蜗外淋巴灌注技术改变豚鼠外淋巴中纳、钾离子浓度,观察其对蜗内电位的影响。实验分高钾、无钾和低纳外淋巴组。经20分钟灌注后,各组豚鼠的蜗内电位均受到显著抑制,其中高钾组的蜗内电位平均下降61%。无钾组的蜗内电位平均下降52%。低纳组的蜗内电位平均下降66%。各组蜗内电位的下降均和外淋巴中纳、钾离子浓度的改变使耳蜗血管纹边缘细胞的纳、钾离子泵受抑制有关。讨论了可能的作用途径。

In order to observe the relationship between endocochlear potential (EP) and the concentration of potassium and sodium in perilymph, the perilymphatic space of guinea pigs was perfusied with various preparations of artificial perilymph for 20 min. EP was depressed by 61% of pre-perfusion value in the group perfused with potssium-high perilymph, 52% in the group using potassium-free perilymph and 66% in the group using sodium deficiency perilymph. The depression of EP may be cused by the inhibition of Na^+-K^+-ATPase activity in the stria vascularis. The results indicated that the normal concentration of potassium and sodium in perilymph is an important factor in maintaining normal EP.