低氧对培养的不同内径的肺动脉平滑肌细胞增殖的影响

目的和方法：分离培养三种不同内径的肺动脉平滑肌细胞（PASMCs）,用^3H－TdR掺入速率和细胞计数作为细胞增殖的指标,观察低氧对其增殖作用的影响。结果：低氧对三种不同内径的PASMCs（内径分别为＞1000μm、500－800μm、300-400μm）增殖促进作用显著不同,其^3H－TdR掺入速率和细胞计数分别增加23.5％和11.1％、60.0％和33.8％、141.4％和52.0％,选择对低氧最敏感的PASMCs（内径为300－400μm）,进一步探讨低氧促PASMCs增殖作用的细胞机制：钙拮抗剂verapail、蛋白激酶C抑制剂staurosporine(Stau)和细胞Na-H交换抑制剂amiloride可显著降低低氧情况下PASMCs^3H－TdR掺入速率和细胞计数。结论：低氧对三种不同内径的PASMCs增殖促进作用显著不同; Ca^2 、蛋白激酶C和Na^2 －H^ 交换的激活,可能是低氧促PASMCs增殖的重要胞内信息转导机制。

Effects of hypoxia on proliferation of pulmonary arterial smooth muscle cells

To investigate the effects of hypoxia on the prolifera tion of different diameter intra-pulmonary artery smooth muscle cells(PASMCs) ,and to study the possible signal transduction pathway in proliferation caused b y hypoxia. Methods: PASMCs were isola-ted from three different size of pulmonary arteries (>1 000 μm. 500～800 μm. 300～400 μm diameter) and cultured separetely.3H-TdR incorporation and cell number were used to measur e cell proliferation. Results:3H-TdR incorporation and cell numbe r of PASMCs from three sizes of pulmonary artery (>1 000 μm, 500～800μm, 800～ 400 μm diameter) increased 23. 5% and 11.1%, 60.0% and 33.8%, 141.4% and 52 .0%, respe ctively. Calcium antagonist (verapail) , PKC inhibitor (staurosporine), and Na +-H+ exchange inhibitor (amiloride) were used in PASMCs isolated from 300～40 0 μm diameter pulmonary artery. The results showed that verapail, stauroporine and amiloride could notably block hypoxia -induced increase 3　H -TdR incorporation and cell number. Conclusion: Proliferation of pu lmonary artery smooth muscle cell responded to hypoxia differently according to the artery size; activation of calcium channel, PKC and Na+-H+ exchange mig ht mediate the proliferation initiated by hypoxia.