Deterioration of rat liver mitochondria under conditions of metabolite deprivation.
Deterioration of rat liver mitochondria under conditions of metabolite deprivation.
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代谢物剥夺条件下大鼠肝线粒体的恶化。
DOI：
10.1042/bj1880817
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发表时间：
1980
期刊：
影响因子：
--
通讯作者：
Cunningham,CC
中科院分区：
文献类型：
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作者：
Parce,JW;Spach,PI;Cunningham,CC
在先前的研究[Parce，Cunningham & Waite（1978）Biochemistry 17，1634-1639]中，当偶联的线粒体在18 ℃的等渗蔗糖溶液中老化时，监测线粒体磷脂代谢和能量相关功能的变化。在上述条件下线粒体退化中发生的事件序列已经被更完整地建立起来。总腺嘌呤核苷酸在衰老过程的早期被耗尽，它们的损失与呼吸控制的下降平行。与总腺嘌呤核苷酸的损失相关的是ADP和ATP转运（摄取）的急剧减少。呼吸控制的下降主要是由于状态3呼吸的减少;这种呼吸活动的丧失可能与ADP易位的下降有关。线粒体ATP酶活性不显着增加，直到状态-4呼吸已明显增加。在失去呼吸控制时，ATP酶活性增加至等于解偶联物刺激的活性。H+/O比和P/O比在呼吸控制丧失之前不会明显降低。类似地，膜对质子被动扩散的渗透性仅在呼吸控制丧失后增加。这些观察结果加强了我们先前的结论，即线粒体衰老有两个主要阶段。第一阶段的特征是腺嘌呤核苷酸易位能力的丧失。第二阶段的特征是质子保存能量（即维持呼吸驱动的质子梯度）和合成ATP的能力下降。
In a previous study [Parce, Cunningham & Waite (1978) Biochemistry 17, 1634-1639] changes in mitochondrial phospholipid metabolism and energy-linked functions were monitored as coupled mitochondria were aged in iso-osmotic sucrose solution at 18 degrees C. The sequence of events that occur in mitochondrial deterioration under the above conditions have been established more completely. Total adenine nucleotides are depleted early in the aging process, and their loss parallels the decline in respiratory control. Related to the loss of total adenine nucleotides is a dramatic decrease in ADP and ATP translocation (uptake). The decline of respiratory control is due primarily to a decrease in State-3 respiration; loss of this respiratory activity can be related to the decline in ADP translocation. Mitochondrial ATPase activity does not increase significantly until State-4 respiration has increased appreciably. At the time of loss of respiratory control the ATPase activity increases to equal the uncoupler-stimulated activity. The H+/O ratio and P/O ratios do not decrease appreciably until respiratory control is lost. Similarly, permeability of the membrane to the passive diffusion of protons increases only after respiratory control is lost. There observations reinforce our earlier conclusion that there are two main phases in mitochondrial aging. The first phase is characterized by loss of the ability to translocate adenine nucleotides. The second phase is characterized by a decline in the ability of the mitochondrion to conserve energy (i.e. maintain a respiration-driven proton gradient) and to synthesize ATP.