静止压力对血管平滑肌细胞容积调节性氯电流的影响

Effects of static pressure on volume-regulated chloride currents of vascular smooth muscle cell

目的 观察不同静止压力对血管平滑肌细胞容积调节性氯电流（ICl,vol）的影响.方法 将胚胎鼠血管平滑肌细胞株A10细胞分别在正常大气压下、100、200 mm Hg（1 mm Hg=0.133 kPa）的静止压力下培养,流式细胞仪测试样品的细胞周期与凋亡率,膜片钳全细胞记录技术观察细胞ICl、vol的变化.结果 100 mm Hg静止压力下培养的A10细胞基础电流在＋100 mV和-100 mV分别为（32.08±3.22）、（-12.50±1.34）pA/pF,低渗激活的电流在＋100 mV和-100 mV分别为（77.91±8.38）、（-39.39±5.72）pA/pF,较对照组（20.49±2.30）、（-9.14±1.35）和（42.34±4.34）、（-24.02±2.71）pA/pF显著增强（P〈0.05）;当压力达200 mm Hg时,在＋100 mV和-100 mV电流密度分别为（12.16±1.29）、（-5.80±0.87）pA/pF（Ib）,（28.29±5.20）、（-14.33±2.49）pA/pF（Ihypo）,较对照组显著减弱（P〈0.05）.结论 容积调节性氯通道在静止压力诱导细胞增殖与凋亡过程中发挥了重要作用.

Objective To investigate the change of volume-regulated chloride current（ICl,vol）under different static pressure in vascular smooth muscle cells.Methods A10 vascular smooth muscle cells were cultured at normal atmosphere,100 mm Hg and 200 mm Hg static pressure.Cell cycle and apoptosis rate were analyzed by flow cytometer,and whole cell currents were recorded in A10 cells by patch-clamp.Results Compared to control group[（20.49±2.30）,（-9.14±1.35）pA/pF and（42.34±4.34）,（-24.02±2.71）pA/pF],at the conditions of ＋100 mV and-100 mV,the basal current[（32.08±3.22）,（-12.50±1.34）pA/pF]and hypotonic activated-current[（77.91±8.38）,（-39.39±5.72）pA/pF]were significantly reinforced after exposure of A10 cells to lower static pressure.However the basal current [（12.16±1.29）,（-5.80±0.87）pA/pF]and hypotonic activated-current[（28.29±5.20）,（-14.33±2.49）pA/pF]were attenuated significantly when pressure was 200 mm Hg.Conclusion These findings demonstrated that volume-regulated chloride channel played an important role in static pressure-induced cell proliferation and apoptosis.