Fujino T, Fried B, Takamiya S
Department of Parasitology, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
J Helminthol. 1995 Sep;69(3):195-201. doi: 10.1017/s0022149x00014140.
Cytochrome c oxidase in the mitochondria of the tegument and tegumental and parenchymal cells was examined cytochemically in Echinostoma trivolvis, Zygocotyle lunata, Schistosoma mansoni, Fasciola gigantica and Paragonimus ohirai, trematodes that inhabit different sites in their vertebrate hosts. Clear differences in enzyme activity occurred in the mitochondria of these species, probably reflecting the different energy metabolisms of these worms. Marked aerobic metabolism occurred in S. mansoni and P. ohirai adults that inhabit the host mesenteric veins and the lungs, respectively. The tegument and parenchymal cells of S. mansoni possess relatively few, small mitochondria with tabular cristae which are heavily reactive for cytochrome c oxidase. In P. ohirai, the activity for cytochrome c oxidase in tegumental mitochondria increased gradually from juveniles to adults, reflecting that the respiratory activity increased with growth and the aerobic metabolism is activated when the worms reach the lung. P. ohirai juveniles and adults had two types of mitochondria with different shapes and enzyme activities that were located in two different types of parenchymal cells. The intestinal species, E. trivolvis had mitochondria in the basal aspect of the tegument, and some variations in enzyme activity of their mitochondria in the tegumental and parenchymal cells were observed, suggesting that they possess both aerobic and anaerobic metabolic systems. Z. lunata that live in rodent caeca are devoid of mitochondria in the tegument and have many characteristic mitochondria with undeveloped cristae in the parenchymal cells. Mitochondria of F. gigantica showed weak or no activity for cytochrome c oxidase, suggesting that the worm is well-adapted to an anaerobic environment in the host bile duct.
对棘口吸虫、新月形双睾吸虫、曼氏血吸虫、巨片形吸虫和大平并殖吸虫等寄生于脊椎动物宿主不同部位的吸虫的皮层、皮层细胞和实质细胞线粒体中的细胞色素c氧化酶进行了细胞化学检测。这些物种的线粒体中酶活性存在明显差异，这可能反映了这些蠕虫不同的能量代谢方式。分别寄生于宿主肠系膜静脉和肺部的曼氏血吸虫成虫和大平并殖吸虫成虫呈现明显的有氧代谢。曼氏血吸虫的皮层和实质细胞拥有相对较少、较小且具板层嵴的线粒体，这些线粒体对细胞色素c氧化酶反应强烈。在大平并殖吸虫中，皮层线粒体中细胞色素c氧化酶的活性从幼虫到成虫逐渐增加，这反映出呼吸活性随生长而增加，且蠕虫到达肺部时有氧代谢被激活。大平并殖吸虫的幼虫和成虫有两种形状和酶活性不同的线粒体，分别位于两种不同类型的实质细胞中。肠道寄生的棘口吸虫在皮层基部有线粒体，并且观察到其皮层和实质细胞中线粒体的酶活性存在一些差异，这表明它们同时拥有有氧和无氧代谢系统。生活在啮齿动物盲肠中的新月形双睾吸虫皮层中没有线粒体，其实质细胞中有许多具不发达嵴的特征性线粒体。巨片形吸虫的线粒体对细胞色素c氧化酶显示出微弱或无活性，这表明该蠕虫很好地适应了宿主胆管中的厌氧环境。
