CYPERMETHRIN-INDUCED IN-VIVO ALTERATIONS IN THE CARBOHYDRATE-METABOLISM OF FRESH-WATER FISH, LABEO-ROHITA

Aspects of carbohydrate metabolism under in vivo conditions were analyzed in functionally different tissues of the freshwater fish, Labeo rohita, exposed to a lethal (LC(50)/96 hr = 5.24 mu g liter(-1)) and sublethal concentration (0.52 mu g liter(-1)) of cypermethrin for 4 days. All exposed fish exhibited a hyperglycemic condition. An increase in tissue lactate with a decrease in pyruvate, total carbohydrates, and glycogen contents was noted. Activity of lactate dehydrogenase was elevated, indicating a shift toward anaerobiosis. TCA cycle enzymes, namely succinate dehydrogenase and malate dehydrogenase, were inhibited. In most cases changes were more pronounced during a lethal exposure compared to sublethal exposure period. The data indicate that the fish has adopted a compensatory mechanism to derive energy during pyrethroid toxicosis. (C) 1995 Academic Press, Inc.