摘要
目的探讨褪黑素对大鼠脑出血后小胶质细胞激活与超氧化物歧化酶（SOD）活性、丙二醛（MDA）含量变化的影响。方法：30只雄性SD大鼠，随机（随机数字法）分为正常组、假手术组、脑出血模型组（模型组）、褪黑素干预组（褪黑素组）；组内随机分为12h、1d、2d、4d、7d共5个时间点，按Rosenberg法建立脑出血模型，褪黑素组每天腹腔注射1mg／mL褪黑素10mL／kg；透射电镜技术观察脑出血后出血侧皮层小胶质细胞形态；免疫组织化学方法观察脑组织OX42阳性细胞动态表达；黄嘌呤氧化法和硫代巴比妥酸比色法检测脑组织SOD活性及MDA含量。结果透射电镜显示，脑出血后2d时皮层神经元肿胀，小胶质细胞活化，褪黑素组小胶质细胞活化不明显；脑出血后12h时血肿周围可见大量OX42阳性小胶质细胞表达，1d时达到高峰，7d时仍有表达，各时间点褪黑素组0X42阳性细胞表达明显低于模型组（P〈0．05）；脑出血后脑组织MDA含量（nmol／mg prot）显著增加，7d时仍高于正常水平，（0．875±0．098）vs．（0．725±0．061），P〈0．05；SOD活性（U／mg prot）变化则与之相反，（70.46±3．12）vs．（85．86±4．95），P〈0．05。与模型组比较，褪黑素组MDA含量显著降低（P〈0．05），SOD活性升高（P〈0．05）。结论褪黑素对脑出血后神经细胞损伤具有保护作用，其机制可能与褪黑素减轻脑出血导致的氧化应激反应、抑制小胶质细胞活化相关。
Objective To investigate the effects of melatonin on activation of microglia and the changes of superoxide dismutase （SOD） and malondialdehyde （MDA） after intracerebral hemorrhage （ICH） in rats, Methods One hundred and thirty male SD rats were randomly divided into four groups： normal group, sham-operated group, intracerebral hemorrhage model group （Model group） and melatonin intervention group （MT group）. Each group was further divided into 5 subgroups respectively at 12 h, 1 d, 2 d, 4 d and 7 d after modeling. The ICH models were made in SD rats by using Rosenberg methods. Melatonin in dose of 10 mg/kg in solution of 1 mg/mL was given intraperitoneally to rats of MT group. The morphology of microglia was observed under electron microscope. OX42-positive cells were detected by （ABC） methods. The contents of MDA or the activity of SOD was measured respectively by thiobarbituric acid or xanthine oxidation method. Results Electron microscope showed that the activation of microglia cell displayed in ameboid shape and swelling of neuron in hemisphere cortex in model group at 2 d after ICH, the activation of micreglia cell of the cortex was insignificant in MT group. OX42-positive microglia cell in large amount surrounded the hematoma at 12 h after ICH, peaked at 1 d and lasted for 7 d. OX42-pesitive microglia cells in MT group were significantly fewer than that in model group at different intervals after ICH （ P 〈 0. 05 ）. The content of MDA in model group increased significantly after ICH, and higher than that in normal group at 7 d, [ （0. 875 ±0. 098） nmol/mg prot vs. （0. 725 ±0. 061 ） nmol/mg prot, P 〈 0. 05, whereas the activity of SOD changes in the opposite direction, （70.46 ± 3. 12） U/mg prot vs. （85.86 ± 4. 95） /U/mg prot, P 〈 0.05. Compared with model group, the content of MDA were lower and the activity of SOD were higher in MT group after ICH （P 〈 0.05 ）. Conclusion Melatonin provides a protective effect on the damage of nerve cell after ICH. The mechanism might be associated with melatonin by reducing the level of oxidative stress in brain tissue and attenuating the activation of microglia after ICH.
出处
《中华急诊医学杂志》
CAS
CSCD
北大核心
2015年第1期46-50,共5页
Chinese Journal of Emergency Medicine
基金
广西省自然科学基金（桂科青0542040）
关键词
褪黑素
脑出血
小胶质细胞
氧化应激
超氧化物歧化酶
大鼠
Melatonin
Intracerebral hemorrhage
Microglia
Oxidative stress
Superoxide dismutase
Rats
