阿米诺利敏感的小鼠生精细胞离子电流

Currents Sensitive to Amiloride in Mouse Spermatogenic Cells

目的研究记录小鼠生精细胞上表皮钠通道电流。方法应用机械分离获得小鼠单个生精细胞,采用全细胞膜片钳技术记录上皮钠离子通道电流。结果当钳制电位在-50mV、指令电压-100～+40mV、步阶电压10mV,测试脉冲为200ms时,可记录到一快速激活并且不失活的电流。细胞外液中加入1μmol/L的阿米诺利能显著性抑制该电流,并呈现出两类不同的作用(抑制率分别为58.49±9.82%,31.44±5.69%)。结论电流特性和阿米诺利敏感性特征表明,生精细胞上所记录到的电流是上皮钠通道电流。

Objective To observe epithelial sodium channels （ENaC） currents in spermatogenic cells. Method Epithelial sodium channels were obtained in acutely dissociated mouse spermatogenic cells using whole-cell patch clamp. Results The currents were evoked by 200 ms test pulses between -100-＋40 mV in 10 mV increments from a holding potential （HP） of-50 mV. Test pulses elicited rapidly activating and non-inactivating Na^＋ current. Na^＋ currents amplitude were significantly reduced by adding Amiloride （1 μmol/L） to the external solution, and displayed two kinds of inhibition effects （the ratio of 58.49%±9.82%, 31.44%±5.69%）. Conclusion The characteristics of such currents and sensitive to Amiloride all approved that these currents recorded from mouse spermatogenic cells were produced through epithelial sodium channels.