摘要
目的研究NMDA受体亚单位2A(NR2A)反义寡核苷酸对短暂性脑缺血/再灌注大鼠海马CA1区NR2A及其mRNA表达的影响,探讨其在脑缺血/再灌注诱导的大鼠海马神经元损伤中的可能作用机制。方法健康雄性SD大鼠随机分为正常对照组、假手术对照组和缺血/再灌注组。经生理盐水、错义寡核苷酸和反义寡核苷酸预处理后,以四血管阻断法建立短暂性前脑缺血(15 m in)再灌注(24 h、48 h和72 h)动物模型。在确定的时间点进行灌注固定、取材、石蜡包埋和组织切片(片厚8μm),然后行原位杂交和免疫组织化学染色。结果短暂性脑缺血/再灌注后,大鼠海马CA1区NR2A mRNA的表达显著增加,与对照组相比差异有统计学意义(P<0.05);NR2A反义寡核苷酸能显著地抑制这种表达的增加(P<0.05)。短暂性脑缺血/再灌注后,大鼠海马CA1区NR2A的蛋白表达显著降低,与对照组相比差异有统计学意义(P<0.05);经NR2A反义寡核苷酸预处理后,能够进一步增强NR2A蛋白表达的降低,与对照组相比差异有统计学意义(P<0.05)。结论短暂性脑缺血/再灌注后,在大鼠海马CA1区存在转录增强而翻译抑制现象。NR2A反义寡核苷酸能特异性地抑制NR2A mRNA表达的增加,同时能够增强NR2A蛋白表达的降低。NR2A反义寡核苷酸的这种作用很可能与缺血后的翻译抑制以及海马CA1区选择性易损伤相关联。
Objective To investigate the effect of NMDA receptor subunit 2A（NR2A） antisense oligodeoxynucleotides on the expression of NR2A and its mRNA in rat hippocampal CA1 region following transient cerebral ischemia/reperfusion,and to further probe into the possible mechanism of neuronal cell injury induced by cerebral ischemia and reperfusion in rat hippocampus.Methods Healthy male SD rats were randomized into normal control group,sham operation control group and ischemia/reperfusion group.Following pretreatment with saline,missense oligonucleotide and antisense oligonucleotide,the four-vessel occlusion method was employed to establish transient forebrain ischemia（15 min） and reperfusion（24 h,48 h and 72 h） animal models.In determining time,the rats were anesthetized,and then underwent perfusion fixation,sample preparation,paraffin-embedding and tissue sections（8 μm of slice thickness）.The slices were processed by in situ hybridization staining and immunohistochemical staining.Results Following transient cerebral ischemia/reperfusion,the expression of NR2A mRNA significantly increased in CA1 subfield of rat hippocampus（P〈0.05） and the NR2A antisense oligonucleotides could significantly inhibit the increase of this expression（P〈0.05）.Subsequent to transient cerebral ischemia/reperfusion,the expression of NR2A protein significantly decreased in CA1 subfield of rat hippocampus（P〈0.05） and pretreatment with NR2A antisense oligonucleotides could further strengthen the reduction of NR2A protein expression（P〈0.05）.Conclusion Following transient cerebral ischemia/reperfusion,there was the phenomenon of transcription enhancement and translation inhibition in CA1 region of rat hippocampus.NR2A antisense oligonucleotides could specifically inhibit the increase in NR2A mRNA expression,and could simultaneously strengthen the reduction in NR2A protein expression.The effect of NR2A antisense oligonucleotides may be related to the translation inhibition and selective vulnerability in hippocampal CA1 region following ischemia.
出处
《徐州医学院学报》
CAS
2010年第9期561-566,共6页
Acta Academiae Medicinae Xuzhou
基金
江苏省麻醉学重点实验室开放课题(KJS07005)
