通过T型Cav3.1通道的单价电流及其被Mg2+阻断的情况。
Monovalent currents through the T-type Cav3.1 channels and their block by Mg2+.
作者信息
Kurejová M, Pavlovicová M, Lacinová L'
机构信息
Institute of Molecular Physiology and Genetics, Centre of Excellence for Cardiovascular Research, Slovak Academy of Sciences, Slovakia.
出版信息
Gen Physiol Biophys. 2007 Sep;26(3):234-9.
We have investigated the permeability of the Cav3.1 channel for Ca2+ and different monovalent cations and the block of the currents by Mg2+ ions. In the absence of extracellular divalent cations, the Cav3.1 channel was more permeable for Na+ than for Cs+ and impermeable for NMDG+. Monovalent currents were inhibited by Mg2+ of near physiological concentration by three orders of magnitude more effectively than the Ca2+ current. Inhibition of outward, but not inward current by Mg2+ was voltage-dependent. Furthermore, magnesium slowed down channel deactivation presumably by interacting with an open channel state.
我们研究了Cav3.1通道对Ca2+和不同单价阳离子的通透性以及Mg2+离子对电流的阻断作用。在没有细胞外二价阳离子的情况下，Cav3.1通道对Na+的通透性高于对Cs+的通透性，而对NMDG+则不通透。单价电流被接近生理浓度的Mg2+抑制的效率比Ca2+电流高三个数量级。Mg2+对外向电流而非内向电流的抑制作用是电压依赖性的。此外，镁可能通过与开放通道状态相互作用来减缓通道失活。
Zotero 插件