Liu Yong, Hou Xiao-Yu, Zhang Guang-Yi, Xu Tian-Le
Research Center for Biochemistry and Molecular Biology, Xuzhou Medical College, 84 West Huai-hai Road, Jiangsu 221002, Xuzhou, China
Brain Res. 2003 May 16;972(1-2):142-8. doi: 10.1016/s0006-8993(03)02519-8.
To study the mechanism of the L-type voltage-gated calcium channel (L-VGCC) involved in neuronal injury induced by brain ischemia and reperfusion (I/R), transient (15 min) brain ischemia was induced by four-vessel occlusion of Sprague-Dawley (SD) rats. Tyrosine phosphorylation of NR2A and interaction of NR2A with Src and Pyk2 in hippocampus induced by brain ischemia and reperfusion (I/R) were determined by immunoprecipitation and immunoblot(ting). Tyrosine phosphorylation of NR2A in hippocampus was enhanced after I/R. Interaction of NR2A with Src and Pyk2, tyrosine phosphorylation and kinase activity of Src and Pyk2 also increased after I/R. All the increases were partly inhibited by L-VGCC antagonist nifedipine administered to rats 20 min prior to brain ischemia. The results suggested that increase of tyrosine phosphorylation of NR2A induced by I/R had a relation to activation of L-VGCC. Src and Pyk2 interacting with NR2A might also be involved in this regulation of the tyrosine phosphorylation of NR2A induced by I/R.
为研究L型电压门控钙通道（L-VGCC）参与脑缺血再灌注（I/R）诱导神经元损伤的机制，采用四动脉结扎法对Sprague-Dawley（SD）大鼠进行短暂（15分钟）脑缺血。通过免疫沉淀和免疫印迹法测定脑缺血再灌注（I/R）诱导的海马中NR2A的酪氨酸磷酸化以及NR2A与Src和Pyk2的相互作用。I/R后海马中NR2A的酪氨酸磷酸化增强。I/R后NR2A与Src和Pyk2的相互作用、Src和Pyk2的酪氨酸磷酸化及激酶活性也增加。在脑缺血前20分钟给大鼠施用L-VGCC拮抗剂硝苯地平，所有这些增加均受到部分抑制。结果表明，I/R诱导的NR2A酪氨酸磷酸化增加与L-VGCC的激活有关。与NR2A相互作用的Src和Pyk2也可能参与I/R诱导的NR2A酪氨酸磷酸化的这种调节。
