Characterization of an ATP‐modulated large conductance Ca(2+)‐activated K+ channel present in rat cortical neurones.
Characterization of an ATP‐modulated large conductance Ca(2+)‐activated K+ channel present in rat cortical neurones.
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大鼠皮质神经元中存在的 ATP 调节大电导 Ca(2+) 激活 K+ 通道的表征。
DOI：
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
M. Ashford
中科院分区：
文献类型：
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作者：
K. Lee;I. Rowe;M. Ashford
1. 单通道电流记录用于研究大鼠运动皮质急性分离神经元中存在的大电导Ca（2+）激活的K+ (BKCa)通道的特性。将ATP应用于切除的内外斑块的细胞内表面，产生了BKCa通道活性的大量浓度依赖性增加。2. 这种ATP介导的激活依赖于细胞内洗浴液中Mg2+的存在，并被磷酸酶2,3 -丁二酮单肟（BDM）或碱性磷酸酶以及蛋白激酶抑制剂staurosporine， H - 7和PKI减少。3. ADP以依赖于Mg（2+）的方式刺激BKCa通道活性，同时使用PKI或BDM也会抑制这一作用。应用己糖激酶和葡萄糖或应用腺苷酸激酶抑制剂Ap5A可降低ADP的作用。在测试的其他核苷酸中，只有CTP持续激活BKCa通道活性。5. 利用细胞附着的结构，福斯克林或二丁基cAMP的浴液应用刺激了BKCa通道的活性。6. 结果表明，大鼠运动皮层的BKCa通道活性受一种密切相关的激酶活性的调节。cAMP激活剂刺激完整细胞中BKCa通道活性的能力表明该系统可能具有生理重要性。
1. Single channel current recordings were used to study the characteristics of a large conductance Ca(2+)‐activated K+ (BKCa) channel present in neurones acutely dissociated from the rat motor cortex. Application of ATP to the intracellular surface of excised inside‐out patches produced a large, concentration‐dependent increase in BKCa channel activity. 2. This ATP‐mediated activation was dependent upon the presence of Mg2+ in the intracellular bathing solution and was diminished by the phosphatases 2,3‐butanedione monoxime (BDM) or alkaline phosphatase and by the protein kinase inhibitors staurosporine, H‐7 and PKI. 3. ADP stimulated BKCa channel activity in a Mg(2+)‐dependent manner, an action also inhibited by the concomitant application of PKI or BDM. The effect of ADP was reduced by application of hexokinase and glucose or by application of the adenylate kinase inhibitor Ap5A. 4. Of other nucleotides tested, only CTP consistently activated BKCa channel activity. 5. Using the cell‐attached configuration, bath application of forskolin or dibutyryl cAMP stimulated BKCa channel activity. 6. It is concluded that BKCa channel activity in the rat motor cortex is subject to modulation by the activity of a closely associated kinase. The ability of cAMP activators to stimulate BKCa channel activity in the intact cell suggests that this system may be of physiological importance.
DOI：
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发表时间：
1989-12
期刊：
The Journal of biological chemistry
影响因子：
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作者：
P. Cohen;P. Cohen
通讯作者：
P. Cohen;P. Cohen