Department of Surgery/Otolaryngology, UCSD School of Medicine and VA Medical Center, La Jolla, California 92093, USA; Department of Neurosciences, UCSD School of Medicine and VA Medical Center, La Jolla, California 92093, USA.
Mol Cell Neurosci. 1991 Apr;2(2):179-87. doi: 10.1016/1044-7431(91)90011-c.
The distributions of mRNAs coding for three different isoforms of the alpha and two of the beta subunits of Na,K-ATPase were studied in the rat cochlea using in situ mRNA hybridization. The alpha1 and beta1 subunit isoforms were widely distributed and appear to mediate the Na and K transport needs of most cochlear cells. The mRNAs encoding the alpha2 and alpha3 subunit isoforms were present in glial and neuronal types, respectively. The only subunit isoform mRNAs found in the stria vascularis were alpha1 and beta2. This suggests that Na,K-ATPase consisting of the alpha1 and beta2 subunits plays a critical role in the maintenance of high extracellular K(+) levels in the cochlear endolymph and appears to transport K(+) ions against very low levels of intracellular potassium.
使用原位 mRNA 杂交技术研究了大鼠耳蜗中编码 Na,K-ATPase 的三种不同α亚基和两种β亚基同工型的 mRNA 分布。α1 和β1 亚基同工型广泛分布，似乎介导了大多数耳蜗细胞的 Na 和 K 转运需求。编码α2 和α3 亚基同工型的 mRNAs 分别存在于神经胶质和神经元类型中。血管纹中仅发现的亚基同工型 mRNAs 是α1 和β2。这表明由α1 和β2 亚基组成的 Na,K-ATPase 在维持耳蜗内淋巴中高细胞外 K(+)水平方面发挥着关键作用，并且似乎在细胞内钾水平非常低的情况下运输 K(+)离子。
