摘要
目的:研究新生大鼠脑缺氧缺血后不同时间点血红素加氧酶-1(hemeoxygen-ase,HO-1)、Caspase-3在海马神经元中的动态变化及纳洛酮注射液的干预作用,进一步探讨HO-1、Caspase-3在新生大鼠缺氧缺血后神经损伤过程中的可能机制及纳洛酮注射液对神经系统保护的作用。方法:新生7天龄SD大鼠随机分为3组:假手术组(S)、生理盐水对照组(C)、纳洛酮干预组(N),每组按照观测的时间点不同分为3、6、12、24 h和3、7天6个亚组,每个亚组8只,用Rice法制备新生大鼠HIBD模型。在每个时间点将大鼠断头取右侧海马脑组织匀浆,用Western blot方法测不同时间点HO-1、Caspase-3动态变化;用TUNEL染色法检测相应时间点脑海马CA1区细胞凋亡。结果:①Western蛋白印迹S组海马HO-1表达很弱,各时间点表达无差异(P>0.05);C组和N组右侧海马HO-1在HI后3h即明显增加(P<0.01),HI后24 h海马HO-1蛋白表达达到峰值,3天后明显下降,7天接近S组,但仍较正常偏高(P<0.01);N组在12、24 h和3、7天海马HO-1表达均较C组高(P<0.01)。②在HI后3 h,C组和N组右侧海马Caspase-3即明显增加(P<0.01),HI后24 h海马Caspase-3蛋白表达达到峰值,3天后明显下降,7天接近S组(P=0.519);N组在12、24 h、3天海马HO-1表达均较C组低(P<0.01)。③Tunel显示S组各时间点右侧海马CA1区仅见少量凋亡细胞,HI后3 h C组和N组右侧海马神经元凋亡细胞数即明显增加(P<0.01),24 h达到高峰,3天开始下降,7天时仍高于S组(P<0.01);N组凋亡数在24 h、3、7天这3个时间点上均较C组明显下降(P<0.01)。结论:HI后脑海马组织细胞中HO-1蛋白、Caspase-3表达均是增加的,两者表达趋势相一致,在时间上吻合,表明HO-1、Caspase-3参与了新生大鼠HI后细胞凋亡的病理过程;纳洛酮注射液能够上调HO-1的表达,抑制Caspase-3活化,减少神经元凋亡,从而起到对HIBD新生大鼠保护作用。
Objective： To study the dynamic changes of heine oxygenase - 1 （ HO - 1 ） and Caspase - 3 in hippocampal neurons of neonatal rats with hypoxic - ischemic brain damage （HIBD） at different time points and the intervention effect of Naloxone injection, further explore the possible mechanisms of HO - 1 and Caspase - 3 in nerve injury of neonatal rats after HIBD and the protective effect of Naloxone injection for nervous system. Methods： Seven - day neonatal SD rats were randomly divided into three groups： sham operation group, normal saline control group, and Naloxone intervention group; the rats in the three groups were divided into six subgroups according to the observa- tion time ： 3 - hour subgroup, 6 - hour subgroup, 12 - hour subgroup, 24 - hour subgroup, 3 - day subgroup, and 7 - day subgroup, 8 rats in each subgroup; HIBD models of neonatal rats were established by Rice method. The right hippocampal tissue was obtained at every time point, and then homogenate was prepared, Western blot was used to detect the dynamic changes of HO - 1 and Caspase - 3 contents at differ- ent time points; TUNEL staining was used to detect apoptosis of hippocampal cells in CA1 region at corresponding time points. Results： In sham operation group, the expression of HO - 1 displayed by Western blot was weak, and there was no statistically significant difference a- mong different time points （ P 〉 0. 05 ） . The expression levels of HO - 1 in right hippoeampal tissues of normal saline control group and Nal- oxone intervention group increased significantly at 3 hours after hypoxia and ischemia （ P 〈 0. 01 ） , the expression levels of HO - 1 peaked at 24 hours after hypoxia and isehemia, then reduced at 3 days after hypoxia and ischemia, the expression levels at 7 days after hypoxia and is- chemia were similar to that in sham operation group, but the levels were still statistically significantly higher than normal levels （P 〈0. 01 ） . The expression levels of HO - 1 in Naloxone intervention group at
出处
《中国妇幼保健》
CAS
北大核心
2012年第27期4272-4276,共5页
Maternal and Child Health Care of China
基金
徐州科技计划项目〔XZZD0921〕
