Activation of a novel non-selective cation channel by alloxan and H2O2 in the rat insulin-secreting cell line CRI-G1
Activation of a novel non-selective cation channel by alloxan and H2O2 in the rat insulin-secreting cell line CRI-G1
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DOI：
10.1111/j.1469-7793.1997.059bo.x
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发表时间：
1997-05-15
影响因子：
5.5
通讯作者：
Ashford, MLJ
中科院分区：
文献类型：
--
作者：
Herson, PS;Ashford, MLJ
1. 四氧嘧啶及其自动氧化产物过氧化氢 (H2O2) 不可逆地使胰岛素瘤去极化。通过打开非选择性阳离子通道来激活细胞。打开的通道的特征是线性电流-电压关系，电导约为70 pS，动力学非常慢（秒级）。2． H2O2 和羟基自由基清除剂的存在可以保护细胞免受四氧嘧啶诱导的通道开放和随后的细胞去极化的影响。3．自由基激活的非选择性阳离子通道在孤立的斑块中不起作用，但可以通过将 β-NAD(+) 应用于膜的细胞质方面来激活。
1. Alloxan and its auto-oxidation product hydrogen peroxide (H2O2) irreversibly depolarize insulinoma. cells by opening a non-selective cation channel. The channel opened is characterized by a linear current-voltage relation with a conductance of approximately 70 pS and very slow kinetics (of the order of seconds).2. Cells are protected against the alloxan-induced channel opening and consequent cell depolarization by the presence of H2O2 and hyrdroxyl radical scavengers.3. The free radical-activated non-selective cation channel is not operative in isolated patches but can be activated by the application of beta-NAD(+) to the cytoplasmic aspect of the membrane.