大鼠肺动脉平滑肌细胞缺氧后STAT3活性变化与细胞增殖关系的研究  

RELATIONSHIP BETWEEN EXPRESSION OF STAT3 GENE AND PROLIFERATION OF RAT PULMONARY ARTERIAL SMOOTHMUSCLE CELLS UNDER HYPOXIA CONDITIONS

作　　者：白莉[1] 余祖滨[2] 钱桂生[1] 李淑萍[1] 

机构地区：[1]第三军医大学附属新桥医院全军呼吸内科研究所,重庆400037 [2]第三军医大学附属新桥医院胸外科,重庆400037

出　　处：《中国应用生理学杂志》2006年第1期75-79,共5页Chinese Journal of Applied Physiology

基　　金：国家自然科学基金资助项目(39970329)

摘　　要：目的:探讨信号转导及转录活化因子3(STAT3)对缺氧大鼠肺动脉平滑肌细胞(PASMCs)增殖的影响及作用机制。方法:组织块法原代培养PASMCs,用AG490预孵育后进行缺氧处理,半定量RT-PCR,Western blot法分别检测缺氧2h、6h、12h、16h、24h组STAT3酪氨酸活性水平变化;半定量RT-PCR检测缺氧条件下上述时相点c-myc mRNA水平变化;3H-TdR掺入法观察缺氧条件下细胞增殖变化。结果:Western blot定量分析显示缺氧培养6h组STAT3酪氨酸磷酸化水平升高,12h组达高峰,16h略有下降;缺氧培养2h组c-myc mRNA表达升高,4h达高峰,6h下降,12h恢复至正常水平;3H-TdR掺入法结果显示缺氧6h组细胞3H-TdR掺入量的增加,并随缺氧时间延长变化更为显著。AG490抑制缺氧诱导STAT3酪氨酸磷酸化及c-myc mRNA表达。结论:①STAT3活化和c-myc表达参与缺氧PASMCs增殖;②在缺氧PASMCs增殖过程中STAT3上调c-myc表达。Aim： To explore the relationship between expression of signal transduction and activators of transcription 3 （STAT3） gene and proliferation of rat pulmonary arterial smooth muscle cells（PASMCs） under hypoxia conditions. Methods： After primarily cultured rat PASMCs was treated with AG490 and then exposed to hypoxia, the tyrosine-phosphorylated STAT3 protein were detected at 2 h, 6 h, 12 h, 16 h, 24 h of exposure to hypoxia by semi-quantitive RT-PCR（sqRT-PCR） and Western blot respectively. The expression of c-myc mRNA was analyzed by sqRT-PCR. 3H-TdR incorporation was used to detect the cell proliferation. Resnlts： The level of ty- rosine-phosphorylated STAT3 increased at 6 h and peaked at 12 h. The expression of c-myc mRNA increased after 2 h of hypoxia and reached maximal level at 4 h, then declined at 6 h and to the basal levels at 12 h. With the prolonging of hypoxia time,3H-TdR in corporation in PASMC under hypoxia conditions was significantly higher. AG490 inhibited proliferation of PASMCs by preventing STAT3 tyrosine phasphorylation and the expression of c myc ander bypoxia conditions. Conclusion： ① The activation of STAT3 and c-myc gene might play an important role in the early stage of hypoxia-induced PASMCs proliferation. ②STAT3 upregulated the expression of c-myc during the proliferation of PASMCs induced by hypoxia.

关 键 词：缺氧 信号传导 肺动脉 平滑肌细胞 增殖 

分 类 号：R734[医药卫生—肿瘤]