POTENTIAL BIOMARKERS OF DICHLORVOS INDUCED NEURONAL INJURY IN RATS

The present study was designed to develop suitable biochemical markers of chronic dichlorvos exposure using rat as the animal model. Animals were exposed to dichlorvos (6 mg kg(-1) (body weight) day(-1)) for 8 weeks and the activities of five potential markers were assayed. Acety lcholinesterase, assayed as an index of cholinergic function, was foun d to decrease in both haemolysate and brain tissue. Cytochrome oxidase , used as a marker of impaired energy metabolism, was also seen to dec rease in platelets and brains of dichlorvos-treated animals. However, acid phosphatase, a lysosomal marker of tissue injury, was increased i n both serum and brains of experimental animals. Chronic dichlorvos ex posure also led to a decrease in the activity of glucose-6-phosphate d ehydrogenase, which was assayed in brain as an index of oxidative stre ss. Dichlorvos administration did not affect 2', 3'-cyclic nucleotide phosphohydrolase. The present study therefore, indicates that apart fr om acetylcholinesterase, which is probably a non-specific marker of di chlorvos neurotoxicity, the levels of cytochrome oxidase, acid phospha tase and glucose-6-phosphate dehydrogenase may serve as useful determi nants of dichlorvos-induced neuronal injury.