【摘要】 目的探讨大鼠脑缺血性神经损伤后脑红蛋白(NGB)对受损神经元轴突生长能力的调控作用及其机制。方法将30只SD大鼠随机分为假手术组、模型组、Hemin组,每组10只,模型组、Hemin组采用双侧颈总动脉结扎的方法制备脑缺血模型,假手术组只暴露双侧颈总动脉但不穿线结扎。Hemin组于术后第1天腹腔注射50 mg/kg NGB诱导剂Hemin,每天1次。2周后比较各组大鼠神经功能评分,采用HE染色观察海马CA1区细胞形态学变化,采用Western blot法检测脑组织中NGB、神经丝-200 (NF-200)、生长相关蛋白-43(GAP-43)、磷脂酰肌醇3激酶(PI3K)、磷酸化的蛋白激酶B(P-AKT)蛋白水平。结果 Hemin组大鼠神经功能评分明显高于假手术组,且明显低于模型组(P <0. 05)。HE染色结果显示,Hemin组大鼠海马CA1区锥体细胞形态及分布趋于正常,核固缩现象及水肿较模型组明显减少。Hemin组大鼠脑组织中NGB、NF-200、GAP-43蛋白表达量均明显高于假手术组和模型组(P <0. 05)。假手术组、Hemin组大鼠脑组织中PI3K、P-AKT蛋白表达量明显高于模型组(P <0. 05),且Hemin组明显低于假手术组(P <0. 05)。结论NGB可以促进受损神经元轴突再生,对脑缺血性神经损伤有改善作用。更多还原

【Abstract】 Objective To investigate the regulary effect and mechanism of neuroglobin( NGB on axonal regeneration of injured neurons after cerebral ischemic nerve injury in rats. Methods Thirty SD rats were randomly divided into sham operation group,model group and Hemin group,each with 10 rats.Rats in model group and Hemin group were made into cerebral ischemia models by permanent bilateral common carotid artery occlusion,while rats in sham operation group received exposure but no occlusion of the bilateral common carotid. In Hemin group,rats were injected with Hemin once a day( 50 mg/kg,i. p.). Indexes were detected by various methods after two weeks,including neurological function score,morphological changes of hippocampal CA1 area by HE staining,as well as Western blotting for protein expression levels of NGB,neurofilament-200( NF-200),growth associated proteins-43( GAP-43),phosphatidylinositol 3-kinase( PI3 K) and phosphorylated protein kinase B( P-AKT). Results The neurological function scores of Hemin group was significantly higher than that of sham operation group,while significantly lower than that of model group( P < 0. 05). HE staining showed that the morphology and distribution of pyramidal cells in hippocampal CA1 area of Hemin group tended to be normal,and the phenomenon of nuclear pyknosis and edema were significantly reduced compared with the model group.The expression of NGB,NF-200 and GAP-43 in brain tissue of hemin group was significantly higher than that of sham operation group and model group( P < 0. 05). The expression of PI3 K and P-Akt in sham operation group and Hemin group was significantly higher than that in model group( P < 0. 05),and that in Hemin group were lower than that in sham operation group( P < 0. 05). Conclusion NGB can promote axon regeneration of injured neurons and ameliorate the brain ischemic injury.更多还原