Abstract：
The mitochondria of adult and plerocercoid Spirometra mansoni were characterized in isolated mitochondria and in situ by electron microscopic histochemistry with special attention to the respiratory chain. Although the specific activities of the constituent enzyme complexes of succinate oxidase are fairly similar in adult and plerocercoid mitochondria, those of succinate oxidase and NADH-FRD are approximately 4- and 25-fold higher in adult mitochondria than in plerocercoid mitochondria, respectively. Quinone analysis by high performance liquid chromatography and mass spectrometry showed that adult and plerocercoid mitochondria contained both rhodoquinone-10 and ubiquinone-10 at concentrations of 4.98 and 0.106 nmol mg-1 for adult, and 0.677 and 0.137 nmol mg-1 for plerocercoid, respectively. Inhibition studies on the succinate-oxidase system of adult mitochondria showed that they possessed both cyanide-sensitive and -insensitive succinate oxidases, the latter of which produces hydrogen peroxide. Adult mitochondria, when NADH was used as a substrate, were shown to produce hydrogen peroxide, and the production of hydrogen peroxide decreased to undetectable levels in the presence of fumarate. The specific activities of NADH-fumarate reductase and cytochrome c oxidase were significantly higher in mature proglottids than in immature and gravid proglottids. Isopycnic density-gradient centrifugation analyses and in situ electron microscopic histochemistry revealed that both adult and plerocercoid mitochondria were heterogeneous in terms of respiratory function and physicochemical properties. The physiological significance of adult and plerocercoid mitochondria is discussed in relation to the oxygen tension of their parasitic habitats.
摘要：
成年和plerocercoidSpirometramansoni的线粒体在分离的线粒体中进行了表征，并通过电子显微镜组织化学在原位进行了表征，并特别注意了呼吸链。尽管琥珀酸氧化酶的组成酶复合物的比活性在成年线粒体和类线粒体中相当相似，成人线粒体中琥珀酸氧化酶和NADH-FRD的含量约为成体线粒体的4倍和25倍，分别。通过高效液相色谱和质谱分析的醌分析表明，成人和plerocercoid线粒体中同时含有4.98和0.106nmolmg-1浓度的杜松醌10和泛醌10，和0.677和0.137nmolmg-1的plerocercoid，分别。对成年线粒体琥珀酸氧化酶系统的抑制研究表明，它们同时具有氰化物敏感和不敏感的琥珀酸氧化酶，后者产生过氧化氢。成年线粒体，当NADH用作底物时，被证明会产生过氧化氢，在富马酸盐的存在下，过氧化氢的产量下降到检测不到的水平。NADH-富马酸还原酶和细胞色素c氧化酶的比活性在成熟的前声体中明显高于未成熟和妊娠的前声体。等密度密度梯度离心分析和原位电子显微镜组织化学显示，成年线粒体和球形线粒体在呼吸功能和理化性质方面都是异质的。讨论了成年线粒体和类线粒体的生理意义与其寄生栖息地的氧张力有关。
