Abstract
Our previous work showed that repeated exposure to methyl parathion (MP) caused a prolonged inhibition of acetylcholinesterase (AChE) activity (approximately 80%) and down-regulation of M(1) and M(2) muscarinic receptors (up to 38%) in rats at brain regions, including frontal cortex, striatum, hippocampus and thalamus. In the present neurobehavioral study, we found this repeated MP treatment had suppressant effects on rat's locomotor activity. However, we observed no evidence of long-term effects of MP on associative learning and memory. Our data demonstrated that repeated exposure to MP caused some functional deficits in CNS, but motor activity and associative learning/memory process might differ in the sensitivity to its toxic effect. The motor dysfunctions in MP-treated rats may be mediated via reciprocal balance between cholinergic and dopaminergic systems at striatum following cholinergic over-stimulation. Our findings also suggest that the CNS deficits induced by repeated exposure to MP or other organophosphate (OP) pesticides cannot be attributed entirely to the inhibition of AChE. To accurately assess the neuro-toxic risk by occupational exposure to sub-lethal doses of MP, novel biomarkers besides in vivo anticholineste...Continue Reading
References
Aug 1, 1992·Clinical Neuropharmacology·B R Ott, M C Lannon
Aug 1, 1989·Behavioral Neuroscience·R W RussellS D Lauretz
Jan 1, 1987·Progress in Neurobiology·R W Russell, D H Overstreet
May 1, 1987·Pharmacology, Biochemistry, and Behavior·M Upchurch, J M Wehner
Jul 1, 1986·Toxicology and Applied Pharmacology·R C GuptaW D Dettbarn
Jan 1, 1969·Annals of the New York Academy of Sciences·D R Metcalf, J H Holmes
Apr 1, 1984·Fundamental and Applied Toxicology : Official Journal of the Society of Toxicology·A G Karczmar
May 1, 1983·Journal of Neurochemistry·S P SivamI K Ho
Jun 1, 1984·Pharmacology, Biochemistry, and Behavior·J C FernandoI K Ho
Jul 1, 1984·Pharmacology, Biochemistry, and Behavior·R GardnerR Robichaud
Sep 30, 1982·Toxicology and Applied Pharmacology·L G Costa, S D Murphy
Dec 1, 1993·Pharmacology, Biochemistry, and Behavior·M S CousinsJ D Salamone
Feb 1, 1993·Fundamental and Applied Toxicology : Official Journal of the Society of Toxicology·J LlorensW R Mundy
Apr 1, 1996·Neuroscience·J L Góngora-AlfaroJ Aceves
Jan 4, 1998·Pharmacology, Biochemistry, and Behavior·D L CarrieroJ D Salamone
May 7, 1999·Journal of Toxicology and Environmental Health. Part B, Critical Reviews·C N Pope
Jun 1, 1999·Biomedicine & Pharmacotherapy = Biomédecine & Pharmacothérapie·D G Le CouteurP G Board
Jul 12, 2001·Toxicology and Applied Pharmacology·D A JettG L McLemore
Jul 30, 2002·Journal of Biomedical Science·Robert E KramerRodney C Baker
Jun 24, 1961·Lancet·S GERSHON, F H SHAW
Jan 30, 2004·The Journal of Toxicological Sciences·Tingting SunIng K Ho