Meng Fan-jie, Guo Jun, Song Bo, Yan Xue-bo, Zhang Guang-yi
Research Center of Biochemistry and Molecular Biology, Xuzhou Medical College, Xuzhou 221002, China.
Acta Pharmacol Sin. 2004 Feb;25(2):176-80.
To investigate the interactions among postsynaptic density 95 (PSD-95), Ca2+-calmodulin dependent protein kinase IIalpha (CaMKIIalpha), and N-methyl-D-aspartate receptor subunit 2B (NR2B) during ischemia and reperfusion in hippocampus of rats.
Brain ischemia was induced by four-vessel occlusion procedure in rats. Immunoprecipitation and immunoblotting were performed to study the interactions and phosphorylation of proteins. The association-dissociation of PSD-95 and CaMKIIalpha to and from N-methyl-D-aspartate (NMDA) receptor induced by ischemia and reperfusion and the effects of 1-[N,O-bis-(5-isoquinolinesulfonyl)-N-methyl-L-tyrosyl]-4-phenyl-piperazine (KN-62, a selective inhibitor of CaMKII) on these protein interactions were investigated. Coimmunoprecipitation and immunoblotting were performed for the studies of interactions among proteins.
The alternations of the binding level of PSD-95 and CaMKIIalpha to NR2B during ischemia and reperfusion demonstrated the negative correlation to each other. Pre-administration of KN62 through both cerebral ventricles inhibited the 10 min ischemia-induced increase of the binding of PSD-95 to NR2B and, on the contrary, promoted the binding of CaMKIIalpha to NR2B.
PSD-95 competes with CaMKII to bind to NR2B during ischemia and reperfusion in rat hippocampus.
研究大鼠海马缺血再灌注过程中突触后致密蛋白95（PSD-95）、钙/钙调蛋白依赖性蛋白激酶IIα（CaMKIIα）和N-甲基-D-天冬氨酸受体亚基2B（NR2B）之间的相互作用。
采用四动脉结扎法诱导大鼠脑缺血。通过免疫沉淀和免疫印迹法研究蛋白质之间的相互作用及磷酸化情况。研究缺血再灌注诱导PSD-95和CaMKIIα与N-甲基-D-天冬氨酸（NMDA）受体的结合与解离，以及1-[N,O-双-(5-异喹啉磺酰基)-N-甲基-L-酪氨酰]-4-苯基哌嗪（KN-62，一种CaMKII的选择性抑制剂）对这些蛋白质相互作用的影响。采用共免疫沉淀和免疫印迹法研究蛋白质之间的相互作用。
缺血再灌注期间PSD-95和CaMKIIα与NR2B结合水平的变化呈负相关。经双侧脑室预先给予KN62可抑制缺血10分钟诱导的PSD-95与NR2B结合增加，相反，促进CaMKIIα与NR2B的结合。
在大鼠海马缺血再灌注过程中，PSD-95与CaMKII竞争结合NR2B。
