论文部分内容阅读
目的:通过观察肺动脉平滑肌细胞(pulmonary artery smooth muscle cells,PASMCs)在化学缺氧、细胞膜去极化和血管舒缩活性物质等不同因素作用下线粒体游离钙([Ca2+]mit)的动态变化特点,探讨:[Ca2+]mit与缺氧性肺动脉收缩(hypoxia pulmonary artery constriction,HPV)发生之间的关联。方法:分离成年Wistar大鼠PASMCs进行体外培养,负载线粒体钙荧光指示剂Rhod-5F(5μmol/L),分组施加2mmol/L连二亚硫酸钠(Na2S2O4)化学缺氧、18mmol/LKCl、10-6mol/L血管紧张素II(Ang II)和100μmol/L一氧化氮供体(SIN-1)等不同刺激因素,在激光共聚焦扫描显微镜下观察[Ca2+]mit的动态的变化。结果:用Na2S2O4对PASMCs施加缺氧刺激,[Ca2+]mit荧光强度在缺氧刺激后迅速增高,持续约30s后回降至低于起始值,随后开始回升,达到并逐渐高于起始值,继而于100s缓慢回升,逐渐高于起始时荧光强度;向PASMCs加入KCl后,[Ca2+]mit迅速升高,40s后缓慢下降,于400s后恢复并维持在初始值;向PASMCs加入AngII后,[Ca2+]mit迅速小幅度升高,于20s时开始降低,于100s时至最低,形成低谷平台,持续至400s时逐渐回升,于600s恢复接近初始水平;向PASMCs加入SIN-1后,[Ca2+]mit迅速降低,于80s时降至最低,形成低谷平台持续至160s时开始回升,于200s时回升至平稳水平但仍低于初始值。结论:给予PASMCs缺氧、细胞膜去极化、舒缩血管活性物质等刺激,可以引起线粒体Ca2+发生相应变化,线粒体[Ca2+]mit可能在HPV发生中也起着重要作用。
OBJECTIVE: To observe the dynamic changes of mitochondrial free calcium ([Ca2 +] mit) in pulmonary artery smooth muscle cells (PASMCs) under different conditions of chemical hypoxia, cell membrane depolarization and vasomotor activity, To investigate the relationship between [Ca2 +] mit and hypoxia pulmonary artery constriction (HPV). METHODS: PASMCs from adult Wistar rats were isolated and cultured in vitro. Rhod-5F (5 μmol / L) was loaded on mitochondria of calcium-exposed mitochondria. Groups were treated with 2 mmol / L sodium dithionite (Na2S2O4) L Angiotensin II (Ang II) and 100 μmol / L nitric oxide donor (SIN-1) were used to observe the dynamic changes of [Ca2 +] mit under laser scanning confocal microscope. Results: With hypoxia stimulation of PASMCs with Na2S2O4, the fluorescence intensity of [Ca2 +] mit rapidly increased after hypoxia stimulation and returned to below the initial value after about 30s, then began to rise again and reached a gradually higher value than the initial value , Followed by a gradual rise at 100s, which was gradually higher than the initial fluorescence intensity. After addition of KCl to PASMCs, [Ca2 +] mit increased rapidly and decreased slowly after 40s, restored and maintained at the initial value after 400s. After adding AngII to PASMCs, , [Ca2 +] mit rapidly increased rapidly and began to decrease at 20s, and reached a minimum at 100s, forming a trough platform and gradually rose back to 400s and returned to its initial level at 600s. After adding SIN-1 to PASMCs, Ca2 +] mit decreased rapidly and reached a minimum at 80s. The formation of trough platform continued to rise until 160s, and then returned to a steady level at 200s but still lower than the initial value. Conclusion: PASMCs hypoxia, cell membrane depolarization, vasoconstriction vasoactive substances and other stimuli can cause a corresponding change in mitochondrial Ca2 +, mitochondrial [Ca2 +] mit may also play an important role in the occurrence of HPV.