摘要

Aim : The present study investigated the physiological responses and histopathological changes of Culex pipiens larvae exposed to sublethal concentrations of sodium and calcium hypochlorite. @@@ Methodology : The concentration of total protein, lipids and carbohydrates as well as activity of acetylcholinesterase were determined in larvae using colorimetric methods. The interaction between hypochlorite and fourth instars larvae of was followed through histological sections. @@@ Results : The contents of total protein and total carbohydrates of all larval instars increased following treatment with sublethal concentrations of both hypochlorite compounds. However, treatment of larvae with 1/10 LC50 induced significant reduction in the total carbohydrate content. In addition, treatment of larvae with sublethal concentrations of both hypochlorite compounds induced significant reduction in the total lipid content. Furthermore, the acetylcholinesterase activity significantly decreased in treated first and second larval instars, while increased in treated third and fourth larval instars. @@@ Interpretation : In larvae treated with sublethal concentrations of calcium and sodium hypochlorite, the mid gut cells appeared thinner and flattened, with disappearance of the peritrophic matrix and reduced fat body. The present study suggested that hypochlorite compounds had a pronounced effect on larval metabolic pathways.

全文