急性重复低氧对小鼠脑组织中糖酵解和线粒体氧化磷酸化以及能量负荷的影响

目的 探讨小鼠在重复急性低氧暴露后脑组织中的糖酵解、线粒体氧化磷酸化及能量负荷的变化。方法 成年Balb/c小鼠重复低氧暴露5次,测定每次低氧暴露时的平均耐受时间、体温及第0,1,3,5次低氧暴露后脑组织中的磷酸果糖激酶（PFK）、丙酮酸激酶（PK）、线粒体复合体I活性和磷酸腺苷水平。结果 重复低氧暴露使小鼠低氧耐受性增强,体温降低,脑组织中PFK和PK活性先增高后降低,复合体I活性持续降低,能量负荷保持稳定。结论 重复急性低氧使小鼠脑组织的糖酵解活性出现规律性变化,线粒体的氧化磷酸化受抑制,但能量负荷保持稳定。

Effects of repeated hypoxic exposures on glycolysis, mitochondrial oxidative phosphorylation and energy charge in mouse brain

Objective To study the effects of repeated hypoxic exposures (HEs) on glycolysis, mitochondrial oxi-dative phosphorylation and energy charge in mouse brain. Methods Adult BALB/c mice were repeatedly exposed to hypoxia for 5 times and the standard tolerant time and body temperature were recorded. The activities of PFK, PK and mitochondrial complex Ⅰ in the brain were assayed. Phosphoadenosines and energy charge were measured. Results Repeated HEs prolonged the hypoxic tolerance and reduced the body temperature. The activities of PFK and PK experienced regular changes, with an increase in 1st and 3rd HEs and a decline to control levels in 5th HE. The complex Ⅰ activity continued to decrease during HEs. The energy charge was stable. Conclusion HEs lead to a regular change of glycolysis, a continued inhibition of mitochondrial oxidative phosphorylation, and a main-tained energy charge in the brains of mouse.