Effect of organophosphorus insecticides on phosphorylation of the M_2 muscarinic acetylcholine receptor

作     者：Shuyin Li Liming Zou Carry Pope 

作者机构：Department of Biochemistry and Molecular Biology Basic Medical School of Shenyang Medical College Shenyang 110034 Liaoning Province China Department of Physiological Sciences College of Veterinary Medicine Oklahoma State University Stillwater OK. USA 

出 版 物：《Neural Regeneration Research》 (中国神经再生研究（英文版）)

年 卷 期：2008年第3卷第4期

页      面：406-409页

核心收录：

学科分类：1002[医学-临床医学] 10[医学] 

主　　题：organophosphorus insecticide antagonists G-protein-coupled receptor kinase 2 muscarinicacetylcholine receptor M2 phosphorylation 

摘      要：BACKGROUND： Organophosphorus insecticides may promote the accumulation of acetylcholine at synapses and the neuromuscular junction by inhibiting acetylcholinesterase activity to cause disturbance of neural signal conduction and induce a toxic reaction. Organophosphorus insecticides may act on M2 muscarinic acetylcholine receptors, whose combination with G proteins is regulated by phosphorylation of G protein-coupled receptor kinase 2. OBJECTIVE： To investigate the effects of organophosphorus insecticides on the phosphorylation of G protein-coupled receptor kinase 2-mediated M2 muscarinic acetylcholine receptors and to reveal other possible actions of organophosphorus insecticides. DESIGN, TIME AND SETTING： An observational study, which was performed in the Central Laboratory of Shenyang Medical College, and Department of Physiological Sciences, College of Veterinary Medicine, Oklahoma State University from June 2002 to December 2004. MATERIALS： Paraoxon, parathion, chlorpyrifos, and chlorpyrifos oxon were provided by Chem Service Company, USA, [γ -p^32] ATP and [^35S]GTP γ S by New England Nuclear Life Science Products, and recombinant β 2-adrenergic receptor membrane protein by Sigma Company, USA. METHODS： The M2 muscarinic acetylcholine receptor was extracted and purified from pig brain using affinity chromatography. Subsequently, the purified M2 muscarinic acetylcholine receptor, G protein-coupled receptor kinase 2, and [γ -p^32] ATP were incubated with different concentrations of paraoxon and chlorpyrifos oxon together. The mixture then underwent polyacrylamide gel electrophoresis, and the gel film was dried and radioactively autographed to detect phosphorylation of the M2 muscarinic acetylcholine receptor. Finally, the radio-labeled phosphorylated M2 receptor protein band was excised for counting with an isotope liquid scintillation counter. MAIN OUTCOME MEASURES： Effects of chlorpyrifos oxon, paraoxon, chlorpyrifos, and parathion in different concentrations on