Schistosomatium douthitti: carbohydrate metabolism in the adults.

Pathways of carbohydrate metabolism in the adults of Schistosomatium douthitti: were investigated. Histochemical reactions for adenosinetriphosphatase (EC 3.6.1.3) glucose 6-phosphate dehydrogenase (EC 1.1.1.49), phosphogluconate dehydrogenase (EC 1.1.1.43), glycerol-3-phosphate dehydrogenase (EC 1.1.1.8), lactate dehydrogenase (EC 1.1.1.27, 1.1.2.3) isocitrate dehydrogenase (EC 1.1.1.41), succinate dehydrogenase (EC 1.3.99.1), malate dehydrogenase (EC 1.1.1.37), cytochrome oxidase (EC 1.9.3.1), and adenosine triphosphatase (EC 3.6.1.3) were found in the adult worms. Glycogen deposits occurred in the parenchyma.Low oxygen tension immobilized the worms. Tartar emetic, sodium cyanide reduced adult motility in vitro. Manometric experiments demonstrated a respiratory quotient of approximately one. Oxygen uptake was completely inhibited by tartar emetic and partially inhibited by sodium fluoracetate and sodium cyanide. Inhibition by sodium fluoroacetate was partially counteracted by citric acid in the medium.Adults demonstrated an oxygen debt following anaerobic incubation. A maximum of 52% of the glucose consumed under aerobic conditions was excreted as lactic acid. Under anaerobic conditions the amount of lactic acid excreted increased. Acids other than lactic acid were also released. Results indicate that although glycolysis is the major pathway, two additional aerobic pathways also exist, one which is cyanide sensitive and the other cyanide insensitive.     

Studies on metabolism of lung fluke genus Paragonimus. VII. Action of bithionol on glycolytic and oxidative metabolism of adult worms

The present study was carried out in order to obtain information on the mechanism of action of bithionol on Paragonimus westermani (Kerbert 1878). Bithionol stimulated lactic acid production of intact adult worms above the level of the control worms, while it inhibited oxygen consumption of intact adult worms in vitro. Bithionol treatment of adult worms in vivo decreased glycolytic and oxidative metabolism of homogenates of uterine eggs and adult worms.Bithionol inhibited lactic acid formation except when fructose 1, 6-diphosphate (FDP) was used as a substrate in the homogenates of adult worms, and it also inhibited oxygen consumption of homogenates of eggs and adult worms. Bithionol inhibited reduction of methylene blue when succinate was used as a substrate. Bithionol inhibited oxidation of reduced cytochrome c in the 1000g supernatant of homogenates of adult worms. Bithionol inhibited activity of the succinate oxidation in homogenates of adult worms.     

Studies on the in vitro effects of bithionol and menichlopholan on flukes of Clonorchis sinensis, Metagonimus takahashii and Paragonimus miyazakii.

The present study was carried out in order to obtain information on the action of bithionol and menichlopholan on Clonorchis sinensis, Metagonimus takahashii and Paragonimus miyazakii. The drugs inhibited the motility of the newly excysted juveniles and adult worms in vitro. Moreover, the in vitro treatment slightly decreased lactate dehydrogenase activity in homogenates of adult worms. The drug treatments of adult worms in vitro also inhibited the activity of fumarate reductase, malic enzyme, phosphogluconate dehydrogenase and succinate dehydrogenase in the homogenate. In addition to this, these drugs caused morphological alterations in the ultrastructure of the tegument of the flukes.     

Schistosoma mansoni and Biomphalaria glabrata: Ultrastructural localization of enzymes with diaminobenzidine in larvae and host digestive glands.

All mitochondria contained reaction product when daughter sporocysts of Schistosoma mansoni and digestive glands of the snail host, Biomphalaria glabrata, were cytochemically incubated for 45 or 60 min with alkaline 3, 3′-diaminobenzidine (DAB) at pH 7.4 and 9.0. The pigment marked the presence of cytochrome c-cytochrome oxidase activity, and was not found in parasite or gland tissues incubated with DAB and KCN at pH 7.4, 9.0, and 9.8.After incubation for 45 min in the pH 7.4 DAB medium, tegumental mitochondria in young intrasporocyst cercariae showed DAB reaction product, but little or none of the pigment was found in tegumental mitochondria of older, glycocalyx-covered cercariae. In contrast, mitochondria of subtegumental cells were strongly DAB positive at all stages of intrasporocyst cercarial development. No differences in DAB reactivity were detected in mitochondria of sporocysts, or of infected and uninfected host gland cells.Reaction product was found in certain vacuoles of digestive cells incubated in the pH 9.8 DAB medium with KCN, but not in the pH 9.8 DAB medium with amino triazole, or in the pH 7.4 DAB medium. No peroxisomes or microperoxisomes were found in the tissues studied.