自噬抑制剂氯奎对低氧诱导肺动脉平滑肌细胞增殖的影响

目的：探讨自噬抑制刺氯喹（cQ）在低氧（hypoxia）调节肺动脉平滑肌细胞（PASMCs）增殖中的作用。方法：将体外培养的大鼠PASMCs分为4组：正常对照组、1％低氧组、50μmol／L氯喹＋1％低氧组、50ttmol／L氯喹组。MTF方法检测各组的PASMCs增殖率；MDC染色检测细胞自噬空泡的变化；Westernblot方法检测微管相关蛋白轻链3（LC3）蛋白的表达变化；划痕法检测细胞迁移的变化。结果：与对照组比较，氯喹组的PASMCs细胞增殖率无明显变化。与对照组比较，1％低氧组PASMCs增殖率明显增加，细胞内出现大量自噬空泡，细胞迁移速度明显增加。细胞LC3-Ⅱ蛋白表达增强。与1％低氧组比较，氯喹与低氧联合作用时细胞自噬空泡的积聚以及rE3．II蛋白表达增强，但细胞增殖率和迁移明显降低。结论：低氧激活自噬过程并促进了PASMCs增殖和迁移，而自噬抑制剂氯喹在一定程度上通过抑制自噬进程，达到抑制肺动脉平滑肌细胞增殖和迁移的作用。

Effect of autophagy inhibitor chloroquine on the proliferation of PASMCs induced by hypoxia

Objective： To investigate the role of autophagy inhibitor chloroquine （CQ） in the proliferation of pulmonary arterial smooth muscle ceUs （PASMCs）in hypoxia conditions. Methods： The following groups in this study were sot up： control group, hypoxia group, 50 /~mol/L CQ ＋ hypoxia group, 50 p.mol/L CQ group. The viability of PASMCs in every group was detected by MIT assay. Autophagic vac- uoles in the cells were observed by MDC staining. Protein expression of microtubule associated protein light chain 3 （LC3） was measured by Western blot. Migration of PASMCs was detected by wound healing assay. Results： Compared with control group, no effect on the viability of PASMCs was observed treated by CQ alone. In 1% hypoxia group, cell viability increased significantly compared with that in control group. The number of autophagic vacuoles and the rate of cell migration and also protein expression of LC3-II were also markedly increased. Compared with hypoxia group, addition of CQ increased the number of autophagic vacuoles and the levels of LC3-II protein, but decreased the prolifera- tion and migration of PASMCs. Conclusion： Hypoxia could activates autophagy and contributes to proliferation and migration of PASMCs, and autophagy inhibitor CQ could decrease the effect of hypoxia on PASMCs through inhibiting autophagy process.