钙敏感受体在缺氧诱导的大鼠肺动脉平滑肌细胞增殖中的作用

目的:观察钙敏感受体(CaSR)在缺氧诱导的大鼠肺动脉平滑肌细胞增殖中的作用。方法:Ⅱ型胶原酶消化法提取、培养大鼠肺动脉平滑肌细胞。应用Western blotting技术及免疫荧光染色分析CaSR蛋白在肺动脉平滑肌的表达;采用激光共聚焦扫描技术检测不同处理因素对细胞内钙离子浓度(Ca2+]i)的影响,应用MTT法分析不同处理因素对细胞存活率的影响。结果:大鼠肺动脉平滑肌细胞有CaSR蛋白表达。缺氧能够增加CaSR和增殖细胞核抗原(PCNA)的表达、细胞存活率及Ca2+]i(与对照组比较,P0.05)。GdCl3(CaSR激动剂)能够增强缺氧的上述作用,NPS2390(CaSR抑制剂)则能够减弱缺氧的作用。结论:缺氧诱导的CaSR表达增加参与了缺氧性肺动脉平滑肌细胞增殖。

Role of calcium-sensing receptor in hypoxia-induced proliferation of rat pulmonary artery smooth muscle cells

AIM: To explore the role of calcium-sensing receptor (CaSR) in rat pulmonary artery smooth muscle cells (PASMCs) and its effect on hypoxia-induced proliferation of PASMCs. METHODS: The expression and distribution of CaSRs were detected by Western blotting and immunofluorescence observation. The intracellular concentration of free calcium (Ca]_i) was determined by confocal laser scanning microscopy. The cell viability was analyzed by MTT assay. The expression of PCNA and CaSRs was determined by Western blotting. RESULTS: CaSR protein was expressed in rat PASMCs. Hypoxia significantly increased the expression of CaSR and PCNA,Ca]_i and the cell viability. GdCl₃ (an agonist of CaSR) or NPS2390 (an antagonist of CaSR) amplified or weakened the effect of hypoxia, respectively.CONCLUSION: CaSR is expressed in rat PASMCs. The activation of CaSR is involved in the proliferation of PASMCs induced by hypoxia.