The effect of chronic ethanol consumption on temperature-dependent physical properties of liver mitochondrial membranes.
The effect of chronic ethanol consumption on temperature-dependent physical properties of liver mitochondrial membranes.
复制标题
慢性乙醇消耗对肝线粒体膜温度依赖性物理特性的影响。
DOI：
10.1016/0003-9861(82)90187-4
复制
发表时间：
1982
影响因子：
3.9
通讯作者：
Rubin,E
中科院分区：
文献类型：
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作者：
Waring,AJ;Rottenberg,H;Ohnishi,T;Rubin,E
在完整的大鼠线粒体膜和来自这些膜的磷脂囊泡的运动，顺序和分区的自旋探针的温度依赖性的慢性乙醇消耗的影响进行了研究。在来自慢性酒精动物的完整膜中，与对照组中的20 °C相比，在约26 °C下，顺序和运动参数（5-doxylstearic acid）以及5-doxyldecane的分配系数（5 N10）发生突变。这种温度的变化与先前报道的呼吸和ATP酶活性的Arrhenius图的变化平行（H。Rottenberg，D. E. Robertson和E.鲁宾，1980年，实验室。Invest.42，318-326）。在从提取的磷脂制备的囊泡中观察到类似的变化，从而证实了这些变化是由脂质结构的分子排序改变引起的。慢性酒精大鼠的膜和磷脂囊泡显示出显着的高阶参数。类似地，在整个温度范围内，来自慢性酒精动物的膜中硝基氧癸烷5 N10的分配系数较低。这些发现表明这些膜的刚性增加。而乙醇，在体外，大大提高了分区5 N10进入正常膜，它几乎没有影响其分区进入膜从慢性酒精大鼠。这些发现，加上我们最近的观察，即在高温下，慢性酒精动物的细胞膜对乙醇的无序作用有抵抗力（A。J. Waring，H. Rottenberg，T. Ohnishi和E. Rubin，1981，Proc. Nat. Acad. Sci. USA 78，2582-2586），可以解释这些膜对乙醇解偶联的抗性。我们认为，线粒体膜的磷脂组成的自适应调整导致刚度增加，这是表现为从乙醇喂养的大鼠的线粒体膜的物理性质的温度依赖性的变化。虽然这些调整往往保持足够的耦合效率在慢性酒精大鼠，他们也可能导致许多乙醇诱导的线粒体改变以前报道。
The effects of chronic ethanol consumption on the temperature dependence of the motion, order, and partition of spin probes were investigated in both intact rat mitochondrial membranes and phospholipid vesicles derived from those membranes. In intact membranes from chronic alcoholic animals an abrupt change in the order and motion parameters (5 doxylstearic acid), as well as in the partition coefficient of 5-doxyldecane (5N10), occurs at about 26 °C, compared to 20 °C in the control. This shift in temperature parallels the shifts in Arrhenius plots of respiration and ATPase activities previously reported (H. Rottenberg, D. E. Robertson, and E. Rubin, 1980,Lab. Invest.42, 318–326). Similar shifts are observed in vesicles prepared from extracted phospholipids, thus confirming the suggestion that these changes result from an alteration in molecular ordering of the lipid structure. Membranes and phospholipid vesicles from chronic alcoholic rats show significantly higher order parameters. Similarly, the partition coefficient of the nitroxydecane, 5N10, is lower in membranes from chronic alcoholic animals over the entire temperature range. These findings indicate increased rigidity of these membranes. While ethanol,in vitro, greatly enhances the partition of 5N10 into normal membranes, it has almost no effect on its partition into the membranes from chronic alcoholic rats. These findings, together with our recent observation that, at high temperature, membranes from chronic alcoholic animals are resistant to the disordering effect of ethanol (A. J. Waring, H. Rottenberg, T. Ohnishi, and E. Rubin, 1981,Proc. Nat. Acad. Sci. USA78, 2582–2586), may explain the resistance of these membranes to uncoupling by ethanol. We suggest that an adaptive adjustment of the phospholipid composition of mitochondrial membranes causes increased rigidity, which is manifested by shifts in the temperature dependence of the physical properties of the mitochondrial membranes from ethanol-fed rats. Although these adjustments tend to preserve adequate coupling efficiency in chronic alcoholic rats, they may also lead to many of the ethanol-induced mitochondrial alterations previously reported.