Acute lethal and chronic sublethal toxic stress induced alterations in lactate dehydrogenase activity of phorate intoxicated freshwater fish Cyprinus carpio

Abstract

Cyprinus carpio fish were exposed to acute lethal toxicity (LC50/96 h) of phorate (ALTP) for one day and 4 days and chronic sublethal toxicity (one-tenth of the LC50/96 h) of phorate (CSTP) for 1, 7, 15 and 30 days and the lactate dehydrogenase (LDH) enzyme activity was observed in the target organs of the fish such as gill, liver, muscle, kidney and brain. Relative to controls, a significant increase was observed in the activity of LDH in all the target organs of the fish exposed to both acute and chronic toxicity of phorate (ACTP). On comparison, the elevation in the LDH activity is more in all the target organs of the fish exposed to the ALTP. The results obtained demonstrate that the ¬lethal and sublethal concentrations of phorate have some deleterious effect on the basic activities of the enzyme LDH in all the target organs of the experimental fish.