Rela Lorena, Piantanida Ana Paula, Bordey Angelique, Greer Charles A
Departments of Neurosurgery, Yale University School of Medicine, New Haven, Connecticut.
Systems Neuroscience Section, Department of Physiology and Biophysics, School of Medicine, University of Buenos Aires, Argentina.
Glia. 2015 Sep;63(9):1646-59. doi: 10.1002/glia.22834. Epub 2015 Apr 9.
The olfactory nerve is permissive for axon growth throughout life. This has been attributed in part to the olfactory ensheathing glial cells that encompass the olfactory sensory neuron fascicles. Olfactory ensheathing cells (OECs) also promote axon growth in vitro and when transplanted in vivo to sites of injury. The mechanisms involved remain largely unidentified owing in part to the limited knowledge of the physiological properties of ensheathing cells. Glial cells rely for many functions on the properties of the potassium channels expressed; however, those expressed in ensheathing cells are unknown. Here we show that OECs express voltage-dependent potassium currents compatible with inward rectifier (Kir ) and delayed rectifier (KDR ) channels. Together with gap junction coupling, these contribute to the heterogeneity of membrane properties observed in OECs. The relevance of K(+) currents expressed by ensheathing cells is discussed in relation to plasticity of the olfactory nerve.
嗅觉神经在一生中都允许轴突生长。这部分归因于包围嗅觉感觉神经元束的嗅鞘胶质细胞。嗅鞘细胞（OECs）在体外以及移植到体内损伤部位时也能促进轴突生长。所涉及的机制在很大程度上仍未明确，部分原因是对鞘细胞生理特性的了解有限。胶质细胞的许多功能依赖于所表达的钾通道的特性；然而，在鞘细胞中表达的那些钾通道尚不清楚。在这里，我们表明OECs表达与内向整流器（Kir）和延迟整流器（KDR）通道相符的电压依赖性钾电流。与缝隙连接耦合一起，这些促成了在OECs中观察到的膜特性的异质性。结合嗅觉神经的可塑性讨论了鞘细胞所表达的K(+)电流的相关性。
