Involvement of mitochondrial Na+-Ca2+ exchange in intestinal pacemaking activity

瞄准：Cajal (国际计算中心) 的空隙的房间是产生慢波浪在的心律调整器房间胃肠(官方补给) 道。我们试图在 Cajal 的有教养的空隙的房间在肠的步调调整的活动调查 mitochondrial Na+-Ca2+ 交换的参与。方法：酶的消化被用来声言不赞成一只老鼠的小肠。整个房间的斑夹钳配置被用来记录膜电流(电压 clamp ) 和潜力(电流夹钳) 从有教养的国际计算中心。结果：Clonazepam 和 CGP37157 以一种剂量依赖者方式禁止了国际计算中心的步调调整的活动。从 20 ～ 60 micromol/L 的 Clonazepam 和从 10 ～ 30 micromol/L 的 CGP37157 有效地在国际计算中心的步调调整的活动从线粒体禁止了 Ca2+ 流出。clonazepam 和 CGP37157 的 IC50s 分别地是 37.1 和 18.2 micromol/L。到内部答案的 20 micromol/L NiCl2 的增加引起了一“打蜡”并且衰退国际计算中心的步调调整的活动的现象。结论：这些结果建议 mitochondrial Na+-Ca2+ 交换在肠的步调调整的活动有一个重要角色。

AIM： Interstitial cells of Cajal （ICCs） are the pacemaker cells that generate slow waves in the gastrointestinal （GI） tract. We have aimed to investigate the involvement of mitochondrial Na^＋-Ca^2＋ exchange in intestinal pacemaking activity in cultured interstitial cells of Cajal. METHODS： Enzymatic digestions were used to dissociate ICCs from the small intestine of a mouse. The whole-cell patch-clamp configuration was used to record membrane currents （voltage clamp） and potentials （current clamp） from cultured ICCs. RESULTS： Clonazepam and CGP37157 inhibited the pacemaking activity of ICCs in a dose-dependent manner. Clonazepam from 20 to 60 μmol/L and CGP37157 from 10 to 30 μmol/L effectively inhibited Ca^2＋ efflux from mitochondria in pacemaking activity of ICCs. The ICsos of clonazepam and CGP37157 were 37.1 and 18.2 μmol/ L, respectively. The addition of 20 μmol/L NiCl2 to the internal solution caused a ＂wax and wane＂ phenomenon of pacemaking activity of ICCs. CONCLUSION： These results suggest that mitochondria Na^＋-Ca^2＋ exchange has an important role in intestina pacemaking activity.