脉络宁对新生鼠缺氧缺血后大脑皮质兴奋性氨基酸和一氧化氮合酶的影响

Effects of Mailuoning to Excitatory Amino Acid and Nitric Oxi de Synthase in Cerebral Cortex of Neonatal Sprague-Dawely Rats after Hypoxia-I schemia

目的研究新生SD鼠缺氧缺血(HI)后大脑皮质谷氨酸(GLU)和天冬氨酸(ASP)的变化,观察脑神经元一氧化氮合酶(NOS)的免疫活性表达,探讨脉络宁对HI性脑损伤(HIBD)的保护作用。方法结扎新生7日龄SD大鼠右侧颈总动脉1h(缺血1 h),吸入8%氧气和92%氮气2 h(缺氧2 h),建立HIBD模型。用色谱分析仪测定右侧大脑皮质内GLU和ASP含量,在透射电镜下观察假手术、HI及脉络宁注射液治疗组新生大鼠右侧大脑皮质神经元超微结构变化。结果HI后大脑皮质兴奋性氨基酸(EAA)水平升高,脉络宁治疗组大脑皮质EAA明显减少,HI后大脑皮质神经元超微结构损伤明显,脉络宁治疗组大脑皮质神经元的超微结构破坏轻微。结论脉络宁通过改善神经元功能,减少EAA释放,对神经元起保护作用。

Objective To study changes of aspartate（ASP） and glutamaic acid （GLU） in cerebral cortex of new,natal Sprague- Dawely（ SD） rats after hypoxia- ischemia and nitric oxide synthase（NOS） immunoactive expression in cerebral neurons were examined to explore mailuoning＇s protective effect on hypoxia-ischemia brain damage（HIBD）. Methods The HIBD model was established as follows. The right common carotids of the neonatal SD rats 7 days were temporaily ligatured for I hour. Then the neonatal SD rats were exposed to 8% oxygen and 92% nitrogen gas mixture for 2 hours. The ASP and GLU were determined m right cerebral certex using chromatograph,compared with sham-operated group and mailuoning administrated. Uhrastructure changes of ueurons in the right cerebral cortex of neonatal SD rats were observed after sham- operated, hypoxia- ischemia and mailuoning administrated using electronmicroscope. Results The level of excitatory amino acid was promoted in right cerebral cortex after bypoxia-ischemia. The vohmc of excitatory. amino acid was reduced sharply mailuoning administrated. Ultrastructure of neurons in the cerebral cortex showed serious injure after hypoxia - ischemia and ultrastructure of neurons in the cerebral cortex appeared slight damage. Conclusion Mailuoning may possess protective effects to the neurons after hypoxia - ischemia through supplying blood to neurons reducinc release of excitatory amino acid.