肾性高血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 DERIVED FROM RENAL HYPERTENSIVE RAT

作　　者：姜雨鸽[1] 徐龙河[1] 米卫东[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：《中国应用生理学杂志》2006年第3期263-267,共5页Chinese Journal of Applied Physiology

基　　金：国家重点科技攻关项目(969010101)

摘　　要：目的：观察肾性高血压大鼠（RHR）肺动脉平滑肌细胞膜电容（Em）、膜电流（I）、电流密度（pA／pF）、膜电位和I-V曲线的变化及盐酸埃他卡林对正常血压及肾性高血压大鼠肺动脉平滑肌钾通道的影响。方法：用内径为0．2～0．3mm的银夹夹住大鼠左肾肾动脉起始部．制成两肾一夹RHR模型．血压以无创性套尾法测量。急性分离大鼠肺内动脉平滑肌细胞．用全细胞记录技术记录细胞钾电流、膜电容并计算电流密度。结果：RHR肺动脉平滑肌细胞膜电容均值为（3．43±1．16）pF，比正常血压大鼠（NTR，4．98±0．62pF）降低31．1％；钾电流值为（0．54±0．26）nA．比正常大鼠（1．70±0．67nA）降低68．2％；电流密度值为（180±90）pA／pF，比正常大鼠（350±80pA／pF）降低48．6％；膜电位为（-26．96±7．23）mv．比正常大鼠（-27．66±7．1mV）降低2．5％。盐酸埃他卡林在0．1—100μmol．L^-1浓度下，可显著增强正常血压大鼠动脉平滑肌钾电流；在1．0—100μmol．L^-1浓度下，可显著增强肾性高血压大鼠动脉平滑肌钾电流。结论：RHR的膜电容、膜电流、电流密度比正常血压大鼠低，I—V曲线下移。盐酸埃他卡林对正常血压大鼠及肾性高血压大鼠动脉平滑肌钾电流都有增强作用。Aim： To investigate the differences of membrane capacitance, membrane current, current density and I-V curves between smooth muscle cells isolated from RHR and NTR pulmonary arteries. Methods： Under antiseptic conditions, the left renal artery was exposed through a retroperitoneal flank incision and carefully dissected free of the left renal vein. A silver clip with an internal diameter of 0.2 - 0.3 mm was placed around the left renal artery, resulting in partial occlusion of renal perfusion. SBP was observed by tail blood pressure. Whole cell recordings were made from smooth muscle cells freshly isolated from pulmonary arteries derived from RHR or NTR. Results： The average of membrane capacitance was （3.43 ± 1.16） pF, decreased by 31.1% ; membrane current was （0.54 ± 0.26） hA, decreased by 68.2 % ; current density was （180 ± 90）pA/pF, decreased by 48.6 % ;membrane potential was（ - 26.96 ± 7.23 ）mV, decreased by 2.5 %, all compared with that of NTR respectively. Iptakalim hydrochloride at the concentration of 0.1 - 100 μmol/L can significantly increased NTR potass/um currents. Iptakalim hydrochloride 1 - 100 μmol/L can significantly increased RHR potassium currents. Conclusion： Membrane capacitance,membrane current, membrane potential were decreased, I-V curves were shift downward, compared with that of NTR. Iptakalim hydroehloride might significandy increase NTR and RHR potassium currents.

关 键 词：两肾一夹 血管平滑肌 膜电位 膜电流 膜电容 电流密度 

分 类 号：R645.1[医药卫生—外科学]