Adverse Outcomes of Repeated Chlorpyrifos- Ethyl and Methyl Exposure in Rats: The Ameliorating Role of N-Acetylcysteine

The ameliorating effect of 150 mg/kg b.w. of N-acetylcysteine (NAC) against the oral administration of 7.88 (1/25 LD_50) or 202.07 (1/10 LD_50) mg/kg/day for 14 days of chlorpyrifos- ethyl (CPF-E) and chlorpyrifos-methyl (CPF-M), respectively, was investigated using neurobehavioral and biochemical markers for this toxicity. Neurobehavioral tests; open field test (OFT), hole-board test (HBT), light/dark box test (LDBT) and elevated plus maze (EPM) showed increase frequency of exploration, low level of anxiety and locomotor in rats treated with either CPE-E or CPF-M, while the co- administration of NAC to treated rats attenuated neurobehavioral parameters. Biomarkers such as acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), paraoxonase (PON) and adenosine 5 -triphosphatase, (ATP-ase) showed declining in their activities, while calcium (Ca^+2) levels in brain were increased. However, the administration of NAC following the intoxification of CPF-E or CPF-M attenuated the values of these biomarkers. It can be concluded that NAC can be used to ameliorate the toxicity of certain organophosphorus compounds such as CPF-E and CPF-M and considered it as a choice for the prevention and treatment of either CPF-E or CPF-M -induced toxicity.