A critical role for the inward rectifying potassium channel Kir7.1 in oligodendrocytes of the mouse optic nerve.
A critical role for the inward rectifying potassium channel Kir7.1 in oligodendrocytes of the mouse optic nerve.
复制标题
小鼠视神经少突胶质细胞内向整流钾通道 Kir7.1 的关键作用。
DOI：
10.1007/s00429-020-02043-4
复制
发表时间：
2020
影响因子：
3.1
通讯作者：
Papanikolaou M
中科院分区：
文献类型：
--
作者：
Papanikolaou M
Inward rectifying potassium channels (Kir) are a large family of ion channels that play key roles in ion homeostasis in oligodendrocytes, the myelinating cells of the central nervous system (CNS). Prominent expression of Kir4. 1 has been indicated in oligodendrocytes, but the extent of expression of other Kir subtypes is unclear. Here, we used qRT-PCR to determine expression of Kir channel transcripts in the mouse optic nerve, a white matter tract comprising myelinated axons and the glia that support them. A novel finding was the high relative expression of Kir7. 1, comparable to that of Kir4. 1, the main glial Kir channel. Significantly, Kir7. 1 immunofluorescence labelling in optic nerve sections and in isolated cells was localised to oligodendrocyte somata. Kir7. 1 are known as a K+ transporting channels and, using patch clamp electrophysiology and the Kir7. 1 blocker VU590, we demonstrated Kir7. 1 channels carry a significant proportion of the whole cell potassium conductance in oligodendrocytes isolated from mouse optic nerves. Notably, oligodendrocytes are highly susceptible to ischemia/hypoxia and this is due at least in part to disruption of ion homeostasis. A key finding of this study is that blockade of Kir7. 1 with VU590 compromised oligodendrocyte cell integrity and compounds oligodendroglial loss in ischemia/hypoxia in the oxygen–glucose deprivation (OGD) model in isolated intact optic nerves. These data reveal Kir7. 1 channels are molecularly and functionally expressed in oligodendrocytes and play an important role in determining oligodendrocyte survival and myelin integrity.
