Kuang Yong, Huang Yue-sheng
Institute of Burn Research, Stale Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical University, Chongqing, P. R. China.
Zhonghua Shao Shang Za Zhi. 2007 Aug;23(4):288-91.
To investigate the effect of microtubule depolymerization on mitochondria damage in rat myocardiocytes early after hypoxia.
Myocardiocytes from Wistar rats were isolated according to routine procedure, and they were randomly divided into control group, depolymerization group (with treatment of 4 micromol/L colchicines in the culture medium), hypoxia group, hypoxia and depolymerization group (with treatment of 4 micromol/L colchicines in the culture medium combined with low oxygen tension). The changes in distribution of the mitochondria were examined with laser confocal microscopy, the morphology and the structure of mitochondria was observed by transmission electron microscope, the respiration control ratio (RCR) was determined by respirometer, and the content of adenosine triphosphate (ATP) in endochylema was detected with liquid chromatograph at 20, 30, 60 post-hypoxia minutes (PHM).
In control group, the mitochondria was in granular form, with regular arrangement, while mild changes were observed in depolymerization group. At 20, 30, and 60 PHM, the disarrangement in distribution and morphologic damage were aggravated in hypoxia depolymerization group, and the RCR (1.58 +/- 0.37, 1.51 +/- 0.32, 1.12 +/- 0.11, respectively) were evidently lower than those in hypoxia group (3.85 +/- 0.56, 2.98 +/- 0.44, 1.79 +/- 0.73, respectively, P < 0.01). The content of ATP showed the same tendency at the same time-points (419 +/- 83, 326 +/- 73, 295 +/- 58 ng/mg) compared with hypoxia depolymerization group [(475 +/- 68, 397 +/- 59, 336 +/- 67 ng/mg) in hypoxia group].
The disarrangement in distribution of mitochondria, as well as the damage in mitochondrial structure, respiratory, function and energy metabolism, can be aggravated by microtubule depolymerization after hypoxia, which indicates that microtubule depolymerization plays an important role in the mitochondria damage.
探讨微管解聚对大鼠心肌细胞缺氧早期线粒体损伤的影响。
按常规方法分离Wistar大鼠心肌细胞，随机分为对照组、解聚组（培养基中加入4 μmol/L秋水仙碱处理）、缺氧组、缺氧和解聚组（培养基中加入4 μmol/L秋水仙碱处理并结合低氧张力）。用激光共聚焦显微镜检测线粒体分布变化，用透射电子显微镜观察线粒体形态和结构，用呼吸计测定呼吸控制率（RCR），在缺氧后20、30、60分钟（PHM）用液相色谱仪检测胞浆中三磷酸腺苷（ATP）含量。
对照组线粒体呈颗粒状，排列规则，解聚组有轻度改变。在20、30和60 PHM时，缺氧和解聚组线粒体分布紊乱和形态损伤加重，RCR（分别为1.58±0.37、1.51±0.32、1.12±0.11）明显低于缺氧组（分别为3.85±0.56、2.98±0.44、1.79±0.73，P<0.01）。在相同时间点，ATP含量也呈现相同趋势（419±83、326±73、295±58 ng/mg），与缺氧和解聚组相比[缺氧组为(475±68、397±59、336±67 ng/mg)]。
缺氧后微管解聚可加重线粒体分布紊乱以及线粒体结构、呼吸、功能和能量代谢损伤，提示微管解聚在心肌细胞缺氧早期线粒体损伤中起重要作用。
