摘要
目的：研究表明硫化氢（ H2 S）能调节大脑N-甲基-D-天冬氨酸受体（ N-methyl-D-aspartate receptors ， NMDARs）的功能，但其在脑复苏中的作用仍需进一步阐明。文中通过观察H2 S复合浅低温对大鼠全脑缺血再灌注后海马NMDARs的亚单位NR2A、NR2B及其环磷酸腺苷反应元件结合蛋白（ phospho-cAMP response element binding protein ， p-CREB）信号通路的影响，旨在探讨H2 S是否存在脑复苏作用及其发挥作用的潜在机制。方法雄性SD大鼠随机分为5组（ n＝20）：假手术组、模型组、浅低温组、硫氢化钠（ NaHS）组、浅低温＋NaHS组。采用Pulsinelli-Brierley四血管阻塞法建立大鼠全脑缺血再灌注损伤模型，缺血15 min再灌注即刻NaHS组和浅低温＋NaHS组腹腔注射14μmol/kg NaHS，浅低温组和浅低温＋NaHS组行体表降温至肛温32～33℃。6 h后断头取海马，分别采用分光光度计法测H2 S的含量，Western blot法测NR2A、NR2B以及p-CREB的表达，RT-PCR法测脑源性神经营养因子（ brain derived neurotrophic factor ， BDNF） mRNA的水平，每组分别取4只于再灌注72 h取脑组织行HE染色观察CA1区锥体细胞病理改变。结果①与假手术组海马组织H2S含量（15．2±2．0）nmol/g相比，各组均升高（P＜0．05）；与模型组的H2S含量（25．2±3．5）nmol/g相比，浅低温组（26．5±3．5）nmol/g略升高（P＞0．05），而NaHS组（37．5±4．0）nmol/g和浅低温＋NaHS组（38．7±4．4）nmol/g显著升高（P＜0．05）；②与假手术组相比，各组NR2A、NR2B的灰度值均增高（P＜0．05），且模型组和浅低温组NR2A/NR2B＜1，NaHS组和浅低温＋NaHS组NR2A/NR2B＞1；③与模型组的p-CREB表达（0．55±0．06）相比，浅低温组（0．99±0．15）、NaHS组（1．05±0．12）、浅低温＋NaHS组（1．02±0．15）显著升高（P＜0．05）；与模型组的BDNF mRNA表达量（0．83±0．12）相比，浅低温组（1．11±0．13）、
Objective Research has indicated that hydrogen sulfide（H2S） can regulate the function of N-methyl-D-aspartate re-ceptors（NMDARs） in the brain, but its effect on brain resuscitation requires further investigation.The study was to speculate the effect of H2 S on brain resuscitation as well as the underlying mechanism of neuroresuscitation by investigating the effects of hydrogen sulfide and hypo-thermia on the expression of NR2A, NR2B and phospho-cAMP response element binding protein （p-CREB） of NMDARs in the hippocampus after global cerebral ischemia following by reperfusion. Methods 100 male SD rats were randomly divided into five groups（n=20）：sham operation group, model group, mild hypothermia group, NaHS group, NaHS combined mild hypothermia group.Pulsinelli-Brierley four-ves-sel occlusion method was induced to build the injury rat model by reperfusion after global cerebral ischemia .After 15 minutes＆#39;ischemia, im-mediate injection of 14μmol/kg NaHS was performed intraperitoneally on NaHS group and NaHS combined mild hypothermia group , while skin cooling（rectal temperature=32-33℃） was done on mild hypothermia group and NaHS combined mild hypothermia group .6 hours late,r hip-pocampus were extracted from rat heads.Respectively, spectrophotometer was applied to measure the content of H2S, Western blot for the expres-sions of NR2 A,NR2 B and pC-REB, and RTP-CR for mRNA level of brain derived neurotrophic （BDNF）. HE staining was also performed on brain tissues 72hours after reperfusion on 4 rats from each group to evaluate the pathological changes of pyramidal neurons in CA1 region. R esul ts The content of H 2 S increased in each of the four groups after ischemia-reperfusion compared with sham operation group （ 15.2 ±2.0 nmol/g） （P〈0.05）.In comparison to model group （25.2 ±3.5 nmol/g）, NaHS group （37.5 ±4.0 nmol/g） and NaHS combined mild hypothermia group （38.7 ±4.4nmol/g ） resulted in significant high content of H2S（P〈0.05）, while mild hypothermia
出处
《医学研究生学报》
CAS
北大核心
2014年第7期686-689,共4页
Journal of Medical Postgraduates
基金
国家自然科学基金(81102514)
南京军区南京总医院科研基金(2010Q011)
