Tat-Src reduced NR2B tyrosine phosphorylation and its interaction with NR2B in levodopa-induced dyskinetic rats model

Augmented function of N-methyl-d-aspartate receptor subunit 2B (NR2B) and Src protein tyrosine kinase have been demonstrated to get involved in the pathological mechanisms of dyskinesia. In view of functional interactions between NR2B and Src, we investigated the effects of uncoupling NR2B and Src interactions on dyskinesia by using the Src-derived interfering peptide (Tat-Src). In the present study, valid 6-hydroxydopamine-lesioned parkinsonian rats were treated with levodopa intraperitoneally for 22 days to induce dyskinetic rats model. On day 23, dyskinetic rats received either Tat-Src or Tat-sSrc or vehicle with each levodopa dose. The data showed that in dyskinetic rats model intraperitoneal microinjection of Tat-Src improved dyskinetic behaviors and decreased NR2B tyrosine phosphorylation and the interactions of Src with NR2B induced by chronic levodopa treatment. Besides, Tat-Src also attenuated S-nitrosylation (SNO-Src) and the autophosphorylation (p-Src) of Src, which catalyzed NR2B phosphorylation. These findings suggest that targeting NR2B/Src complexes can be one potential treatment for dyskinesia in Parkinson's disease.