NMDA微量注射对脑皮质细胞磷酸化NMDA受体-1亚基表达的影响  

Expression of phosphorylated NMDA receptor 1 in the cerebral cortex after NMDA microinjection in vivo

作　　者：黑明燕[1] 肖蜜黎[1] 旷寿金[1] 

机构地区：[1]中南大学湘雅三医院新生儿科,湖南长沙410013

出　　处：《中国当代儿科杂志》2007年第1期51-53,共3页Chinese Journal of Contemporary Pediatrics

摘　　要：目的N-甲基-D-天冬氨酸(NMDA)受体激活在多种脑神经细胞损伤的病理生理过程中起重要的作用。该研究的目的是了解NMDA直接诱导的细胞毒性反应对脑皮质神经细胞S897位点磷酸化的NMDA受体-1亚基(phospho-NR1 S897)表达的影响。方法7日龄SD大鼠40只,随机分为正常对照组和NMDA微量注射组(10mmol NMDA脑皮质内注射,于注射后1h断头取材),应用TTC(2,3,5-triphenyltetrazolium chloride)染色和荧光免疫组化染色并比较各组荧光强度OD值。结果各组脑组织切片TTC染色均大致正常;免疫荧光染色显示正常对照组脑皮质phospho-NR1 S897高表达,NMDA注射侧脑皮质phospho-NR1 S897表达明显下调,各组荧光强度OD值分别为正常对照组1.364±0.268,NMDA注射对侧1.285±0.336,NMDA注射侧0.366±0.087,与前2组比较差异有显著性(P<0.01)。结论NMDA直接诱导的细胞毒性反应使脑皮质细胞S897位点的磷酸化NR1亚基的表达显著降低,与HI导致的损伤相类似,进一步证实了缺氧缺血性脑损伤中“HI-NMDA-phospho-NR1 S897去磷酸化-细胞损伤”损伤途径的重要性。Objective The activation of N-methyl-D-aspartate （NMDA） receptors plays critical roles in the pathogenesis of diseases of the brain. This study aimed to examine the expression of phospho-NR1 S897 in the cerebral cortex after NMDA microinjection in vivo. Methods Forty seven-day-old Sprague-Dawley rats were randomly assigned into normal control and NMDA injection groups. The rats from the NMDA injection group were injected with 10 mmol of NMDA and were sacrificed 1 hr after injection. 2, 3, 5-triphenyhetrazolium chloride （Trc） and fluorescent immunohistochemical stainings were conducted and the fluorescence intensity OD value between the two groups was compared. Results TYC staining from the two groups was normal. Expression of phospho-NR1 S897 in the cerebral cortex of the ipsilateral hemisphere to injection in the NMDA injection group decreased significantly compared with the normal control group, with OD values of 0.366 ±0.087 vs 1.364 ±0.268 （P〈0.01）. Condusions NMDA microinjection, as a hypoxia-ischemia （HI） insult, significantly decreased the expression of phospho-NR1 S897. This indicates the importance of the ＂ HINMDA- phospho-NR1 S897 dephosphorylation-cell damage＂ pathway in HI brain damage.

关 键 词：NMDA 微量注射 脑皮质 Phospho—NR1 S897 大鼠 

分 类 号：R722.1[医药卫生—儿科]