乙醇会改变大鼠肝脏线粒体中呼吸作用和ATP酶的温度依赖性。

The temperature dependence of respiration and ATPase in rat liver mitochondria is altered by ethanol.

作者信息

Rottenberg H, Robertson D E, Rubin E

出版信息

Adv Exp Med Biol. 1980;132:345-53. doi: 10.1007/978-1-4757-1419-7_34.

Abstract

We studied hepatic mitochondria to determine the effects of ethanol in vitro and of chronic ethanol consumption on the temperature dependence (10 degrees-45 degrees C) of a) substrate oxidation, and b) ATP hydrolysis, with or without CCCP. Arrhenius plots showed the characteristic breaks around 20 degrees C both for electron transport and ATP hydrolysis with high energy of activation at low temperature and low energy of activation at high temperature. Ethanol, in vitro, generally lowered the energy of activation at high temperature and shifted the break in the Arrhenius plots to lower temperatures suggesting an increase in membrane fluidity. At 40 degrees C and above ethanol accelerated electron transport and greatly stimulated ATPase activity. In mitochondria from ethanol-fed rats, Arrhenius plots showed a shift in the breaks to a higher temperature, a finding which suggests a change in membrane structure, possibly associated with decreased fluidity. This may be an adaption of the mitochondrial membranes to counter the effect of ethanol on membrane structure.

摘要

我们研究了肝线粒体，以确定体外乙醇以及长期摄入乙醇对以下方面温度依赖性（10摄氏度至45摄氏度）的影响：a）底物氧化，以及b）有无羰基氰化物间氯苯腙（CCCP）时的ATP水解。阿累尼乌斯曲线显示，电子传递和ATP水解在20摄氏度左右均出现特征性断点，低温时活化能高，高温时活化能低。体外乙醇通常会降低高温时的活化能，并使阿累尼乌斯曲线的断点向低温方向移动，表明膜流动性增加。在40摄氏度及以上时，乙醇加速电子传递并极大地刺激ATP酶活性。在喂食乙醇的大鼠的线粒体中，阿累尼乌斯曲线显示断点向更高温度偏移，这一发现表明膜结构发生了变化，可能与流动性降低有关。这可能是线粒体膜的一种适应性变化，以对抗乙醇对膜结构的影响。