金枪鱼心室中两种线粒体群体的进一步特征分析。

Further characterization of two mitochondrial populations in tuna heart ventricle.

Greco G, Martino G, Tota B

Comp Biochem Physiol B. 1982;71(1):71-5. doi: 10.1016/0305-0491(82)90177-8.

Abstract

Mitochondria were isolated from the spongy and compact ventricular myocardium of adult Thunnus thynnus thynnus L. 2. Measurement of the succinoxidase activity of phosphorylating mitochondria revealed that those from the spongy had an apparent Km being half of that of the mitochondria from the compact layer. These latter exhibited Km more sensitive to acidic pH values. 3. Succinate-cytochrome c reductase activity was very differently affected by pH and temperature in non-phosporylating mitochondria from the two cardiac layers. 4. The thermostability of the NADH-cytochrome c reductase and the succinate-cytochrome c reductase activities exhibited also marked differences in the two mitochondrial populations. 5. These results, which represent an example of metabolic zonation at the organelle level, are discussed in relation to the homeostatic cooperation of the two myocardial regions of tuna heart.

摘要

从成年蓝鳍金枪鱼的海绵状和致密心室心肌中分离出线粒体。2. 对磷酸化线粒体的琥珀酸氧化酶活性进行测量，结果显示，海绵状心肌中的线粒体表观Km值是致密层线粒体的一半。后者的Km值对酸性pH值更为敏感。3. 来自两个心脏层的非磷酸化线粒体中，琥珀酸 - 细胞色素c还原酶活性受pH和温度的影响差异很大。4. 两种线粒体群体中，NADH - 细胞色素c还原酶和琥珀酸 - 细胞色素c还原酶活性的热稳定性也存在显著差异。5. 这些结果代表了细胞器水平代谢分区的一个例子，并结合金枪鱼心脏两个心肌区域的稳态协同作用进行了讨论。