title: NR2B antagonist CP-101,606 inhibits NR2B phosphorylation at tyrosine-1472 and its interactions with Fyn in levodopa-induced dyskinesia rat model.
abstract: The augmented tyrosine phosphorylation of NR2B subunit of N-methyl-d-aspartate receptors (NMDAR) dependent on Fyn kinase has been associated with levodopa (l-dopa)-induced dyskinesia (LID). CP-101,606, one selective NR2B subunit antagonist, can improve dyskinesia. Yet, the accurate action mechanism is less well understood. In the present study, the evidences were investigated. Valid 6-hydroxydopamine-lesioned parkinsonian rats were treated with l-dopa intraperitoneally for 22 days to induce LID rat model. On day 23, rats received either CP-101,606 (0.5mg/kg) or vehicle with each l-dopa dose. On the day of 1, 8, 15, 22, and 23 during l-dopa treatment, we determined abnormal involuntary movements (AIMs) in rats. The levels of NR2B phosphorylation at tyrosine-1472 (pNR2B-Tyr1472) and interactions of NR2B with Fyn in LID rat model were detected by immunoblotting and immunoprecipitation. Results showed that CP-101,606 attenuated l-dopa-induced AIMs. In agreement with behavioral analysis, CP-101,606 reduced the augmented pNR2B-Tyr1472 and its interactions with Fyn triggered during the l-dopa administration in the lesioned striatum of parkinsonian rats. Moreover, CP-101,606 also decreased the level of Ca(2+)/calmodulin-dependent protein kinase II at threonine-286 hyperphosphorylation (pCaMKII-Thr286), which was the downstream signaling amplification molecule of NMDAR overactivation and closely associated with LID. However, the protein level of NR2B and Fyn had no difference under the above conditions. These data indicate that the inhibition of the interactions of NR2B with Fyn and NR2B tyrosine phosphorylation may contribute to the CP-101,606-induced downregulation of NMDAR function and provide benefit for the therapy of LID.
authors.affiliation: Department of Neurology, Yantaishan Hospital, Yantai City, Shandong 264000, China.
authors.forename: Min
authors.initials: M
authors.lastname: Kong
authors.affiliation: Department of Neurology, Yuhuangding Hospital, Yantai City, Shandong 264000, China. Electronic address: bamaowen@sohu.com.
authors.forename: Maowen
authors.initials: M
authors.lastname: Ba
authors.affiliation: Department of Neurology, Yuhuangding Hospital, Yantai City, Shandong 264000, China.
authors.forename: Chuanyu
authors.initials: C
authors.lastname: Liu
authors.affiliation: Department of Neurology, Yuhuangding Hospital, Yantai City, Shandong 264000, China.
authors.forename: Yanxiang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Endocrinology, Ruijin Hospital Affiliated To Shanghai Jiaotong University School of Medicine, Shanghai 200092, China.
authors.forename: Hongli
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Neuroscience, the University of Texas Southwestern Medical Center, TX 75390, USA.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Qiu
mesh_terms: D000818:Animals; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2 / Q000378:metabolism; D003342:Corpus Striatum / Q000187:drug effects* / Q000378:metabolism; D004195:Disease Models, Animal; D004409:Dyskinesia, Drug-Induced / Q000378:metabolism*; D005260:Female; D007980:Levodopa / Q000633:toxicity; D010766:Phosphorylation / Q000187:drug effects*; D010880:Piperidines / Q000494:pharmacology*; D051076:Proto-Oncogene Proteins c-fyn / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism
chemical_list: C121001:NR2B NMDA receptor; D010880:Piperidines; D016194:Receptors, N-Methyl-D-Aspartate; D014443:Tyrosine; D007980:Levodopa; C095106:traxoprodil mesylate; C494961:Fyn protein, rat; D051076:Proto-Oncogene Proteins c-fyn; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2
keywords: CaMKII; Dyskinesia; Fyn; NR2B; Phosphorylation