NMDA受体亚单位2A在大鼠海马缺血/再灌注损伤中的作用  

The role of NMDA receptor subunit 2A in ischemia/reperfusion injury of rat hippocampus

作　　者：张旭[1] 滕大才[2] 高伟[1] 刘志安[2] 徐铁军[2] 

机构地区：[1]北京大学首钢医院神经内科,北京100144 [2]徐州医学院解剖学和神经生物学教研室,江苏徐州221002

出　　处：《徐州医学院学报》2010年第8期495-499,共5页Acta Academiae Medicinae Xuzhou

基　　金：江苏省麻醉学重点实验室课题(KJS07005)

摘　　要：目的观察NMDA受体亚单位2A(NR2A)特异性反义寡核苷酸阻断大鼠海马CA1区NR2A表达后在缺血性脑损伤中产生的变化,以揭示NR2A在缺血性脑损伤中的作用。方法健康雄性SD大鼠随机分为正常对照组、假手术组和缺血/再灌注组。分别经反义寡核苷酸、正义寡核苷酸、生理盐水对照和空白对照预处理后,以四血管阻断法建立短暂性前脑缺血(15min)/再灌注(24h和48h)动物模型。在确定的时间内进行灌注固定、取材、石蜡包埋和组织切片(片厚8μm),然后行原位杂交染色、TUNEL染色和焦油紫染色。结果缺血/再灌注早期(24h)大鼠海马CA1区NR2AmRNA的表达水平显著增高(P<0.05)。经反义寡核苷酸预处理后,大鼠海马CA1区NR2AmRNA的表达水平显著降低(P<0.05);同时TUNEL染色显示,在缺血/再灌注24h和48h凋亡阳性细胞的数量也明显降低(P<0.05)。结论短暂性前脑缺血后,NR2AmRNA的表达水平与细胞凋亡在时间上和空间上具有一致性,提示NR2A参与了脑缺血/再灌注诱导的细胞凋亡过程。Objective To observe the changes of NMDA receptor subunit 2A (NR2A) expression in rat hippocampal CA1 subfield during ischemia/reperfusion following blockage by NR2A-specific antisense oligonucleotide,and to further reveal the role of NR2A in ischemic brain injury.Methods Healthy male SD rats were randomized into normal control group,sham operation control group and ischemia/reperfusion group.After respective pretreatment with antisense oligonucleotide,sense oligonucleotide,saline and blank control,the four-vessel occlusion method was adopted to establish animal model of transient forebrain ischemia (15 min) and reperfusion (24 h and 48 h) .Within the determined time,the rats were sacrificed for paraffin-embedded tissue sections (slice thickness of 8 μm) .The slices were processed by in situ hybridization staining,TUNEL staining and Cresyl violet staining.Results In the early period of ischemia /reperfusion (24 h) ,the expression of NR2A mRNA in CA1 subfield of rat hippocampus significantly increased (P < 0.05) .Following pretreatment with antisense oligonucleotide,the expression of NR2A mRNA in CA1 subfield of rat hippocampus significantly decreased (P < 0.05) .Meanwhile,TUNEL staining also showed that the number of apoptotic cells significantly decreased at the time points as 24 h and 48 h of ischemia-reperfusion (P < 0.05) .Conclusion After transient forebrain ischemia,the expression level of NR2A mRNA was consistent with the apoptosis in time and space,suggesting that NR2A might be involved in the process of apoptosis induced by cerebral ischemia and reperfusion.

关 键 词：NMDA受体亚单位2A(NR2A) 脑缺血 细胞凋亡 海马 大鼠 

分 类 号：R363[医药卫生—病理学]