INTRACELLULAR ADP ACTIVATES K+ CHANNELS THAT ARE INHIBITED BY ATP IN AN INSULIN-SECRETING CELL-LINE
INTRACELLULAR ADP ACTIVATES K+ CHANNELS THAT ARE INHIBITED BY ATP IN AN INSULIN-SECRETING CELL-LINE
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DOI：
10.1016/0014-5793(86)81532-0
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发表时间：
1986-11-10
期刊：
影响因子：
3.5
通讯作者：
PETERSEN, OH
中科院分区：
文献类型：
--
作者：
DUNNE, MJ;PETERSEN, OH
借助皂苷透化细胞的单通道电流记录，研究了ADP对胰岛素分泌型RINm 5 F细胞系中ATP敏感性K+通道的影响。ADP（100-500 μM）加入到与膜内部接触的浴槽溶液中时，可显著激活K+通道。ADP-β-S不能模拟这种作用。在持续ATP（500 μM）诱发的K+通道开放抑制期间，500 μM ADP显著且可逆地激活通道。相反，ATP显著降低ADP激活通道的开放概率。这表明胰岛素分泌细胞中K+通道开放的生理控制是由ATP/ADP比值的变化介导的，而不仅仅是由ATP浓度决定的。
the effect of ADP on ATP‐sensitive K+channels in the insulin‐secreting RINm5F cell line has been investigated with the help of single‐channel current recording from saponin‐permeabilized cells. ADP (100–500 μM) markedly activates K+channels when added to the bath solution in contact with the membrane inside. ADP‐β‐S cannot mimick this effect. During sustained ATP (500 μM)‐evoked inhibition of K+channel opening, 500 μM ADP markedly and reversibly activates the channels. Conversely ATP markedly reduces the opening probability of ADP‐activated channels. It is suggested that the physiological control of K+channel opening in the insulin‐secreting cells is mediated by changes in ATP/ADP ratio rather than being solely determined by the ATP concentration.