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

Aspects of carbohydrate metabolism under ill vivo conditions were anal yzed in functionally different tissues of the freshwater fish, Labeo r ohita, exposed to a lethal (LC(50)/96 hr = 5.24 mu g liter(-1)) and su blethal 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 ele vated, indicating a shift toward anaerobiosis. TCA cycle enzymes, name ly succinate dehydrogenase and malate dehydrogenase, were inhibited. I n most cases changes were more pronounced during a lethal exposure com pared to sublethal exposure period. The data indicate that the fish ha s adopted a compensatory mechanism to derive energy during pyrethroid toxicosis. (C) 1995 Academic Press, Inc.