过氧化氢对细胞膜上离子通道的作用

H2 O2 对细胞膜上不同的离子通道有广泛的作用 ,而且同一种通道在不同的组织类型中对H2 O2 的反应性亦不同。在培养的lymnaea(椎螺 )神经元中 ,H2 O2 可诱导剂量依赖性的内向Ca2 +电流的降低 ,L 型Ca2 +电流的降低 ,导致通道失活。在绵羊心肌细胞的内质网H2 O2 可直接调节Ca2 +释放通道 ,使其开放概率 (P0 )增加 ,但它不影响电导。H2 O2对K+通道的作用表明 ,H2 O2 介导的KCa通道活性改变因组织类别的不同而亦有差异。H2 O2 可诱导豚鼠心肌细胞ATP 敏感K+通道的活动增加。H2 O2 对全细胞Na+通道的影响及对单通道Na+电流的影响目前报道极少

Effects of hydrogen peroxide on cell membrane ion channels

The H 2O 2 has been shown to have comprahensive actions on various ion channels of cell membrane. But it has different effects on different tissues. H 2O 2 induced a dose dependent decreasing L type Ca 2 current on cultrued Lymnaea neurons. In sheep cardiac SR, H 2O 2 plays an important role in regulating directly on RyR Ca 2 release channel that caused an increasing of P 0, but it was no effects on conductance. It indicated that H 2O 2 induced different activities on K Ca channel with different tissues. In guinea pig ventricular myocytes, H 2O 2 induced increase in K ATP channels. There are few data on the effects of H 2O 2 on whole cell Na currents and single Na channels.