低氧大鼠脑线粒体体外转录活性的研究

STUDIES OF HYPOXIC RAT BRAIN MITOCHONDRIAL TRANSCRIPTION ACTIVITY IN VITRO

目的 :探讨低氧对大鼠脑线粒体DNA表达的影响及其与能量生成的关系。方法 :雄性Wistar大鼠随机分为 3组 :急性低氧组 (AH)、慢性低氧组 (CH)和对照组 ,其中急、慢性低氧组动物分别连续暴露于模拟海拔 40 0 0m高原 3d(AH)和 40d(CH)。分离脑线粒体 ,分别测定线粒体体外转录活性、F0 F1 ATP酶活性以及ATP对线粒体体外转录的影响。结果 :急性低氧大鼠脑线粒体体外转录活性及F0 F1 ATP酶活性显著降低 ,慢性低氧时有所回升 ,两者呈线性相关。ATP对大鼠脑线粒体体外转录活性呈双相效应。结论 :低氧时脑线粒体转录活性改变可能参与低氧抑制线粒体能量代谢的机制 。

Aim: To explore the effects of acute and chronic hypoxia on brain mitochondrial transcription acitvity in vitro of rats. Methods: Animal grouping: Wistar rats were randomized into acute hypoxic group (AH),chronic hypoxic group (CH) and the control. Mitochondrial transcription activity in vitro was measured in each group respectively as well as mitochondrial F 0F 1 ATPase activity,and effects of environmental ATP concentration on mitochondrial transcription activity in vitro was observed. Results: Brain mitochondrial transcription activity and F 0F 1 ATPase activity were marked depressed in AH while partly reversed in CH,and they were linearly related. Mitochondrial transcription activity in vitro was affected by ATP concentration diphasely. Conclusion: Acute hypoxia may impair brain mitochondria energy metabolism by way of depressing mitochondrial transcription and then partially recover during chronic hypoxia. And mitochondrial transcription in vitro might be precisely regulated by ATP concentration.