ATP-sensitive K(+)-channel currents were recorded from isolated membrane patches and voltage-clamped CRI-G1 insulin-secreting cells. Internal Mg2+ ions inhibited ATP-K+ channels by a voltage-dependent block of the channel current and decrease of open-state probability. The run-down of ATP-K+ channel activity was also shown to be [Mg2+]i dependent, being almost abolished in Mg2(+)-free conditions. Substitution of Mn2+ for Mg2+ did not prevent run-down, nor did the presence of phosphate-donating nucleotides, a protease or phosphatase inhibitor or replacement of Cl- by gluconate.

中文翻译：

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ATP敏感的K（+）通道损耗取决于Mg2 +。

从隔离的膜片和电压钳制的CRI-G1胰岛素分泌细胞中记录了ATP敏感的K（+）通道电流。内部Mg2 +离子通过依赖电压的通道电流阻滞和开态概率的降低来抑制ATP-K +通道。ATP-K +通道活性的下降也显示为[Mg2 +] i依赖性，在无Mg2（+）的条件下几乎被废除。用Mn2 +替代Mg2 +不能防止老化，也不能提供磷酸盐供体的核苷酸，蛋白酶或磷酸酶抑制剂或用葡萄糖酸盐替代Cl-。