肺动脉高压大鼠肺动脉平滑肌细胞钾通道的研究  

Studies of potassium channel in pulmonary artery smooth muscle cells of pulmonary hypertension rats

作　　者：姜雨鸽[1] 徐龙河[1] 张宏[1] 汪海[2] 

机构地区：[1]中国人民解放军总医院麻醉科,北京100853 [2]军事医学科学院毒物药物研究所,北京100850

出　　处：《中国病理生理杂志》2006年第8期1554-1557,共4页Chinese Journal of Pathophysiology

基　　金：国家重点科技攻关项目资助(No.969010101)

摘　　要：目的:观察肺动脉高压大鼠(PHR)肺动脉平滑肌细胞膜电容(Cm)、膜电流(I)、电流密度(pA/pF)及I-V曲线,并与正常SD大鼠进行比较。观察盐酸埃他卡林对正常血压及肺动脉高压大鼠动脉平滑肌钾通道的影响。方法:SD大鼠,置于常压缺氧(10%O2)舱内,每天6 h,每周6 d,持续4周,使之平均肺动脉压升高,建立肺动脉高压大鼠模型。急性分离大鼠肺内动脉平滑肌细胞,用全细胞记录(whole cell record ing)技术记录细胞钾电流、膜电容并计算电流密度。结果:PHR肺动脉平滑肌细胞Cm值、细胞膜钾电流值均显著高于正常血压SD大鼠(P<0.05);PHR肺动脉平滑肌细胞钾电流密度值显著低于正常血压大鼠(P<0.05)。与正常SD大鼠比较,PHR钾电流I-V曲线下移。盐酸埃他卡林在10μmol.L-1浓度下,可显著增强正常血压SD大鼠及PHR动脉平滑肌钾电流(P<0.05)。结论:PHR肺动脉平滑肌细胞的膜电容、膜钾电流比正常血压SD大鼠高;钾电流密度比正常血压SD大鼠低,I-V曲线下移。盐酸埃他卡林对正常血压大鼠及肺动脉高压大鼠动脉平滑肌钾电流都有增强作用。AIM： In this work, we investigated the difference of membrane capacitance, membrane current, current density and 1 - V curves between smooth muscle cells isolated from pulmonary hypertension rat （PHR） or normotensire rat （NTR） pulmonary arteries. METHODS： Thirty young male Sprague - Dawley rats, aged 8 -9 weeks, were used. Body weight was （ 200 ± 20） g at the start of experiments. These rats were placed into a normobaric chamber for 6 h · day ^-1, 6 day · week ^-1 for 4 weeks. Hypoxic exposure was accomplished by ventilation with room a/r and N2 resulting in a constant O2 concentration of （ 10 ±0. 5 ）%. Whole cell recordings were made from smooth muscle cells freshly isolated from pulmonary arteries derived from PHR or NTR. RESULTS： The membrane capacitance of pulmonary hypertension rats was larger than that in SD rats; but membrane current and current density were lower than those in SD rats （P 〈0. 05）. The 1 - V curves of pulmonary hypertension rat were downward shift compared with that in SD rat. Iptakalim hydrochloride 10 μmol · L^-1 significantly increased potassium currents. CONCLUSIONS： Membrane capacitance, membrane current, membrane potential are decreased, 1 - V curves was shift downward, compared with NTR. Iptakalim hydrochloride significantly increased NTR and PHR potassium currents.

关 键 词：平滑肌血管 膜电位 膜电流 膜电容 膜片钳术 钾通道 肺动脉高压 

分 类 号：R363[医药卫生—病理学]