AbstractsAstronomy & Space Science

The histopathological and histochemical effects on the snail Oxytrema siliqua, caused by the larvae of Nanophyetus salmincola, have been studied. The parasite causes damage to the organ by increased pressure, active ingestion of the hepatic tubules, and by the increased burden placed upon the snail in disposing of the waste of the parasite. Glycogen uptake from the hepatopancreas by the parasite was studied using the periodic acid Schiff technique. The rediae actively ingest some of the hepatic tissue, and it is suggested that some of the glycogen is transported across the membrane of the parasite as free glucose and resynthesized into glycogen within the developing cercariae. The presence of lipids was demonstrated by using the Nile blue sulfate technique and the oil red O method. Neutral fats were present in small quantities in the unparasitized hepatopancreas, but were greatly increased in the infected hepatopancreas. It is postulated that the parasite stimulates an increase of lipid synthesis in the hepatopancreatic cells of the host. Acid and alkaline phosphatases were determined by using the techniques of Gomori (1940, and 1946). Both enzymes were found to be present in greater quantities in the infected snails. Alkaline phosphatase was found associated with the parasite and is thought to function in the metabolism of glycogen.