Inward and outward rectifying potassium currents set membrane potentials in activated rat microglia

被引:22
作者
Chung, S [1 ]
Jung, W [1 ]
Lee, MY [1 ]
机构
[1] Chung Ang Univ, Coll Med, Dept Physiol, Seoul 156756, South Korea
关键词
microglia; outward rectifying K+ channel; inward rectifying K+ channel; lipopolysaccharide; zero current membrane potential;
D O I
10.1016/S0304-3940(99)00053-1
中图分类号
Q189 [神经科学];
学科分类号
071006 ;
摘要
Activation of cultured rat microglial cells with lipopolysaccharide (LPS), induced outward rectifying K+ (Kv) current in addition to already existing inward rectifying K+ current (K-IR) BY measuring zero-current membrane-potentials using whole-cell patch-clamp method, we showed that K-V current plays a direct role in setting membrane potential to near -45 mV. Since the membrane potentials of microglia show two prominent peaks at -45 and -70 mV, we hypothesize that K-IR current might set the membrane potential to near -70 mV. We observed that cells with larger K-IR current had a zero-current membrane-potential at around -70 mV, and that blocking of K-IR current with Ba2+ depolarized membrane potentials to near -45 mV. These results indicate that the amounts of K-IR, and K-V current determine the zero-current membrane-potentials in LPS-activated microglia. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.
引用
收藏
页码:121 / 124
页数:4
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