微量去甲肾上腺素预处理对线粒体的影响

Effect of Microdosis Norepinephrine’s Preconditioning on Mitochondria of Myocardial Cell

目的研究微量去甲肾上腺素(NA)预处理对心肌细胞线粒体功能的影响,为探讨预适应作用机制提供依据。方法原代培养乳鼠心肌细胞,用含有去甲肾上腺素0.2μg/ml的正常培养液培养10min,再进行缺氧处理,然后继续培养24h,用流式细胞仪检测罗丹明123标记的线粒体的膜电位,用含有去甲肾上腺素0.2μg/ml的正常培养液培养10min后,继续培养24h,在不同的时间点用用流式细胞仪检测罗丹明123标记线粒体的膜电位。结果Ⅰ组和Ⅱ组在缺氧处理前的荧光强度通过成组t检验,t=5.57,P<0.05;Ⅰ组和Ⅱ组在缺氧处理后荧光强度t=1.03,P>0.05;Ⅰ组和Ⅱ组在24h后荧光强度t=2.10,P>0.05;Ⅲ组在12h和24h时间点检测荧光强度t=6.03,P<0.05;Ⅳ组在12h和24h时间点检测荧光强度t检验t=1.00,P>0.05。结论微量去甲肾上腺素预处理使心肌细胞对损伤性刺激的耐受力增强,但是在不同的时间段,具体机制是不同的。结果显示在预适应保护效应的晚时相线粒体内有蛋白质含量增加,提示有蛋白质合成。

Objective To investigate the microdosis Norepinephrine＇ s effect of preconditioning on myocardial cell and discover some new mechanism of action. Methods Neonate rat myocytes were exposed to NA （0. 2ug/ ml） ,then treat it by hypoxia, and continue to culture for 24 hour. The membrane potential of rhodamine - 123 marked mitochondria was detected by flow cytometry at different time marking. Results Group Ⅰ and group Ⅱ fluorescence intensity were test by unitizing t - test （t = 5.57 ,P 〈 0.05） before hypoxia. Group Ⅰ and group Ⅱ fluorescence intensity were test by unitizing t＇- test （ t = 1.03, P 〉 0.05 ） after hypoxia. Group Ⅰ and group Ⅱ fluorescence intensity were test by unitizing t - test （t = 2.10,P 〉 0.05） after 24 hour cultvire. Group Ⅲ fluorescence intensity were test by unitizing t - test （t = 6.03 ,P 〈 0.05 ） at 12. - hour time - marking and 24 - hour time - marking respectively; Group Ⅳ fluorescence intensity were test by unitizing t - test （ t = 1.00,P 〉 0.05 ） at 12. - hour time - marking and 24 - hour time - marking; Respectively. Conclusions Preconditioning will strengthen tolerance of myocardial cell to injuring stimutation by microdosis Norepinephrine with different mechanism during the different time. Some synthesized protein showed in mitochondria and protein content of mitochondria increased during the delayed preconditioning.