新生大鼠缺氧缺血性脑损伤神经细胞凋亡时程

为确定新生大鼠缺氧缺血性脑损伤神经细胞凋亡时程、采用HE染色及TUNEL研究新生大鼠缺氧缺血性脑损伤后神经细胞凋亡情况.结果显示,新生大鼠缺氧缺血后3周时,左脑仍有少量凋亡细胞存在,与对照组比较有显著性差异,P＜0.05;于4周时左脑凋亡细胞数与对照组比较无显著性差异,P＞0.05.结果提示新生大鼠缺氧缺血性脑损伤后神经细胞凋亡持续至损伤后4周.     

高压氧治疗对新生大鼠缺氧缺血性脑损伤模型的保护作用

目的观察高压氧治疗对新生大鼠缺氧缺血性脑损伤(HIBD)的保护作用。方法用2.0 ATA的高压氧对新生大鼠HIBD模型进行治疗,1h/(次·d),治疗7 d后处死。观察各组大鼠死亡率、体质量增长率、左/右脑重量比值、脑组织肉眼病理形态学改变。TUMEL检测大脑皮质和海马神经细胞凋亡情况。结果与HIBD组比较,高压氧治疗可使治疗组大鼠的体质量增长率和左/右脑重量比值增加,大鼠死亡率和脑组织病变减轻、神经细胞凋亡减少。结论高压氧治疗对新生大鼠HIBD 模型具有保护作用。     

石杉碱甲改善新生大鼠缺氧缺血性脑损伤和智能缺陷的实验研究

目的　探讨胆碱酯酶抑制剂———石杉碱甲对新生大鼠缺氧缺血性脑损伤 (hypoxia ischemiabraindamage ,HIBD)智能缺陷的改善和保护作用。方法　将HIBD模型鼠随机分为安慰剂组(n =11)、小剂量石杉碱甲组 ( 0 0 5mg/kg ,n =12 )、大剂量石杉碱甲组 ( 0 1mg/kg,n =12 )和对照组(n =10 ,为假手术组动物 )。以Morris水迷宫成绩判断大鼠学习、记忆功能变化 ;以结扎侧纹状体、皮层、海马损失面积和海马CA1区锥体细胞密度变化及乙酰胆碱酯酶组化染色判定脑组织损伤程度。结果　HIBD后 5周安慰剂组大鼠的学习、记忆功能受损严重 ,水迷宫实验潜伏期 (找到平台时间 )较对照组延长 ( 44s与 3 0s,P <0 0 5 ) ,平台撤除象限搜索时间缩短 ( 14s与 40s,P <0 0 1) ,脑组织损失面积最重 ;而与安慰剂组相比大剂量石杉碱甲治疗明显减轻大鼠的学习、记忆功能障碍 (潜伏期 :3 4s与 44s ,P <0 0 5 ;搜索时间 :3 5s与 14s,P <0 0 1) ,脑组织损失面积较轻 ,小剂量石杉碱甲治疗组大鼠学习、记忆功能改善不明显 (潜伏期 :45s与 44s,P >0 0 5 ;空间搜索时间 :17s与 14s,P >0 0 5 ) ,脑组织损失面积也较重 ;大鼠学习、记忆功能缺陷与海马CA1区锥体细胞密度呈显著相关 (r=0 777,P <0 0 1)。结论　胆碱酯酶抑制剂———石杉碱     

高压氧对新生大鼠缺氧缺血性脑损伤的保护作用

为研究高压氧(HBO)对新生儿缺氧缺血性脑损伤(HIBD)的保护作用,应用新生Wistar大鼠制备HIBD模型,将HBO及HBO+胞二磷胆碱(CDPC)应用于这些模型中,观察它们对HIBD模型鼠的体重增长、病死率、脑病变的影响,并用原位缺口末端标记法(TUMEL)检测HBO对HI后脑细胞凋亡的影响.结果表明CDPC及HBO+CDPC治疗后减轻了病死率及脑病变率;并使HIBD模型鼠体重增长快于未治疗组,但两治疗组间差异不显著;HBO治疗组未明显减轻死亡率及脑病变率,也未明显减轻脑细胞凋亡;CDPC及HBO+CDPC却明显减轻了脑细胞的凋亡(P＜0.001),但两组间差异不显著.因此提示,HBO对HIBD的保护作用尚待定论.     

神经生长因子对新生大鼠缺氧缺血性脑损伤的保护作用

目的：研究神经生长因子(NGF)对新生大鼠缺氧缺血性脑损伤(HIBD)的保护作用。方法：将新生7日龄SD大鼠40只随机分为NGF治疗组(n=16),对照组(n=16)和假手术组(n=8),缺氧缺血(HI)后即刻腹腔注射100 U NGF或等量生理盐水(假手术组不注射),然后观察NGF对HIBD模型鼠的体重增长、脑组织病理及超微结构改变的影响,并用TUNEL法原位标记DNA片段,观察NGF对HIBD后脑细胞凋亡的影响。结果：NGF治疗组体重增长(4.16±0.24) g明显高于对照组(2.86±0.17) g,(P<0.01);TUNEL检测结果,HIBD后24 h治疗组左侧海马和皮质凋亡细胞数(分别为199.75±19.61,182.75±19.12)明显低于对照组(分别为285.50±32.67,271.00±28.36)(P<0.01);HIBD后48 h治疗组左侧海马、皮质凋亡细胞数(分别为77.75±15.76,82.50±19.15)亦明显低于对照组(分别为106.50±16.96,122.75±16.56)(P<0.01)。结论：外源性NGF对HIBD后脑细胞凋亡可能具有一定的保护作用。     

硫酸镁对新生鼠缺氧缺血性脑损伤的保护作用

目的　研究硫酸镁预处理对新生鼠缺氧缺血性脑损伤 (HIBD)的保护作用。方法　采用HE和TUNEL染色分别观察正常对照组、缺氧缺血组、硫酸镁预处理组新生鼠大脑神经细胞组织学改变和细胞凋亡情况。结果　硫酸镁预处理组新生鼠大脑组织病变范围和程度较缺氧缺血组减轻 ,且凋亡细胞数量明显减少。结论　硫酸镁预处理可减轻新生鼠HIBD程度 ,具有神经保护作用     

高压氧对新生大鼠缺氧缺血性脑损伤的保护作用

为研究高压氧（HBO）对新生儿缺氧缺血性脑损伤（HIBD）的保护作用,应用新生Wistar大鼠制备HIBD模型,将HBO及HBO＋胞二磷胆碱（CDPC）应用于这些模型中,观察它们对HIBD模型鼠的体重增长、病死率、脑病变的影响,并用原位缺口末端标记法（TUNEL）检测HBO对HI后脑细胞凋亡的影响。结果表明：CDPC及HBO＋CDPC治疗后减轻了病死率及脑病变率;并使HIBD模型鼠体重增长快于未治疗组,但两治疗组间差异不显著;HBO治疗组未明显减轻死亡率及脑病变率,也未明显减轻脑细胞凋亡;CDPC及HBO＋CDPC却明显减轻了脑细胞的凋亡（P＜0．001）,但两组间差异不显著。因此提示,HBO对HIBD的保护作用尚待定论。     

缺氧缺血性脑损伤新生大鼠脑组织MMP-9和TIMP-1表达的动态变化研究

目的 探讨新生大鼠缺氧缺血性脑损伤(HIBD)的发生机制.方法 建立新生大鼠HIBD模型,随机分为假手术组及HIBD 6 h、12 h、24 h、48 h、72 h组,每组6只.观察脑组织大体病理学改变.采用Real-time Q-PCR方法测定大鼠脑组织MMP-9 mRNA和TIMP-1 mRNA表达.结果 (1)新生大鼠HIBD后12～48 h脑水肿明显,可见点状软化坏死灶.(2)假手术组大鼠MMP-9 mRNA表达水平极低,HIBD组大鼠在缺氧缺血6 h表达开始增高,24 h达高峰,此后渐渐下降,但72 h仍维持较高的水平,与假手术组相比差异有非常显著性(P＜0.01).(3)假手术组大鼠TIMP-1 mRNA表达水平极低,HIBD组大鼠在经历缺氧缺血6、12、24h,TIMP-1 mRNA表达水平有微弱升高,与假手术组相比差异有显著性(P＜0.05),但48 h后TIMP-1 mRNA表达下降到假手术组水平(P＞0.05).(4)MMP-9 mRNA/TIMP-1 mRNA比值在假手术组接近1:1,HIBD组缺氧缺血12 h后比值升高,在48 h达到高峰,72 h有所下降,但仍高于假手术组(P＜0.01).结论 新生大鼠HIBD后可诱导MMP-9 mRNA表达,而MMP-9 mRNA和TIMP-1 mRNA表达的失衡可能参与了HIBD的发病过程.     

缺氧缺血性脑损伤新生大鼠脑组织MMP-9和TIMP-1表达的动态变化研究

Objective To explore the mechanism of hypoxic-ischemic brain damage(HIBD) and provide new ideas for clinical treatment of hypoxic-iscbemic encephalopathy.Methods Neonatal 7-day-old Wistar rats were randomly divided into sham-operation control group,HIBD 6 h,12 h,24 h,48 h and 72 h groups(n =6 per group).The model of HIBD was induced by unilateral carotid ligation followed by timed exposure to 8% oxygen.The expression of MMP-9 mRNA and TIMP-1 mRNA in brain tissue of neonatal rats was measured by Real-time Q-PCR method.Results (1) The ligatod brainhemisphere of HIBD groups showed obvious edema from 12 h to 48 h after hypoxia -ischemia in the neonatal rats.(2) The expression of MMP-9 mRNA was very low in the sham-operation control group,but in HIBD groups,it began to increase at 6 h,and reached a peak at 24 h,then gradually decreased,but still maintained at high level at 72 h(P＜0.01).(3) The expression of TIMP-1 mRNA was aslo very low in the sham-operation control group.But in HIBD group,it increased slightly at 6 h,12 h and 24 h,compared to the sham-operation control group,each group was statistically significant(P＜0.05),with no significant difference among the three groups(P＞0.05),then decreased at 48 h and 72 h,but with no significant difference from sham-operation control group (P＞ 0.05).(4) The ratio of MMP-9 mRNA/TIMP-1 mRNA was normal in the sham-operation control group and HIBD 6 h group,it began to increase at 12 h,and reached a peak at 48 h,then gradually decreased,but still maintained at high level at 72 h(P ＜0.01).Conclusion Hypoxia-ischemia increases the expression of MMP-9 mRNA in brain tissue of nenatal rats,and the imbalance in the expression of MMP-9 mRNA and TIMP-1 mRNA possibly is one cause of brain edema induced by HIBD.     

缺氧缺血性脑损伤新生大鼠脑组织MMP-9和TIMP-1表达的动态变化研究

Objective To explore the mechanism of hypoxic-ischemic brain damage(HIBD) and provide new ideas for clinical treatment of hypoxic-iscbemic encephalopathy.Methods Neonatal 7-day-old Wistar rats were randomly divided into sham-operation control group,HIBD 6 h,12 h,24 h,48 h and 72 h groups(n =6 per group).The model of HIBD was induced by unilateral carotid ligation followed by timed exposure to 8% oxygen.The expression of MMP-9 mRNA and TIMP-1 mRNA in brain tissue of neonatal rats was measured by Real-time Q-PCR method.Results (1) The ligatod brainhemisphere of HIBD groups showed obvious edema from 12 h to 48 h after hypoxia -ischemia in the neonatal rats.(2) The expression of MMP-9 mRNA was very low in the sham-operation control group,but in HIBD groups,it began to increase at 6 h,and reached a peak at 24 h,then gradually decreased,but still maintained at high level at 72 h(P＜0.01).(3) The expression of TIMP-1 mRNA was aslo very low in the sham-operation control group.But in HIBD group,it increased slightly at 6 h,12 h and 24 h,compared to the sham-operation control group,each group was statistically significant(P＜0.05),with no significant difference among the three groups(P＞0.05),then decreased at 48 h and 72 h,but with no significant difference from sham-operation control group (P＞ 0.05).(4) The ratio of MMP-9 mRNA/TIMP-1 mRNA was normal in the sham-operation control group and HIBD 6 h group,it began to increase at 12 h,and reached a peak at 48 h,then gradually decreased,but still maintained at high level at 72 h(P ＜0.01).Conclusion Hypoxia-ischemia increases the expression of MMP-9 mRNA in brain tissue of nenatal rats,and the imbalance in the expression of MMP-9 mRNA and TIMP-1 mRNA possibly is one cause of brain edema induced by HIBD.     

细胞生长肽对新生大鼠缺氧缺血性脑损伤的保护作用

目的研究碱性成纤维细胞生长肽（ｂＦＧＦ）对新生大鼠缺氧缺血性脑损伤（ＨＩＢＤ）的保护作用。方法应用１０５只（ｂＦＧＦ组５８只,未治疗组４２只,对照组５只）新生Ｗｉｓｔａｒ大鼠制备ＨＩＢＤ模型,然后观察ｂＦＧＦ对ＨＩＢＤ模型鼠的体重增长、死亡率、脑损伤的影响,并用原位缺口末端标记（ＴＵＮＥＬ）法检测ｂＦＧＦ对缺氧缺血后脑细胞凋亡的影响。结果ｂＦＧＦ治疗组体重增长为（１２±４）ｇ,明显高于未治疗组（６±４）ｇ,差异有非常显著意义（Ｐ＜０００１）;治疗组病死率（５％）低于未治疗组（２８％）,差异有非常显著意义（Ｐ＜００１）;治疗组脑病变率（２５％）明显低于未治疗组（６２％）,差异有显著意义（Ｐ＜００５）。ＴＵＮＥＬ检测结果,治疗组阳性细胞均数（３０个／５００个细胞）低于未治疗组（１５９个／５００个细胞）,差异有非常显著意义（Ｐ＜０００１）。结论ｂＦＧＦ对ＨＩＢＤ脑组织有修复和促进细胞生长的作用。     

胰岛素对新生大鼠缺氧缺血性脑损伤保护作用的研究

目的探讨胰岛素对新生大鼠缺氧缺血性脑损伤(HIBD)的保护作用.方法建立新生大鼠HIE模型,利用末端转移酶介导的原位缺口标记法,检测缺氧缺血后24h大脑皮质和海马的神经元凋亡情况.结果大脑皮质和海马部位小、中剂量胰岛素组凋亡细胞显著少于对照组;大剂量胰岛素组凋亡细胞数显著多于对照组.侧脑室小剂量胰岛素组血糖水平与对照组无显著差异;中、大剂量胰岛素组血糖水平显著低于对照组.结论适量的胰岛素对新生大鼠HIBD具有保护作用.     

The effect of levetiracetam on neuronal apoptosis in neonatal rat model of hypoxic ischemic brain injury

Background

Hypoxic–ischemic brain injury (HIBI) is a common cause of neonatal mortality and morbidity. The use of levetiracetam (LEV), as a potential neuroprotective in brain ischemia, receives an increasingly high attention, and it could have a crucial role in the regulation of epileptogenesis and neuroprotection. Potential effects of LEV on neuronal apoptosis in HIBI have not previously been reported in literature.

Objectives

The aim of this study is to evaluate the possible effects of LEV on neuronal apoptosis in neonatal rat model of HIBI.

Methods

Seven-day-old Wistar rat pups were subjected to right common carotid artery ligation and hypoxia (92% nitrogen and 8% oxygen) for 2 h. The pups were treated with LEV or saline after hypoxia. In sham group rats, neither ligation, nor hypoxia was performed. Neuronal apoptosis was evaluated by the terminal deoxynucleotidyl-transferase- mediated dUTP nick-end labeling (TUNEL) methods.

Results

The counts of apoptotic cells in both hippocampus and cerebral cortex were significantly higher in the saline treatment group than in the sham group. The counts of apoptotic cells in both hippocampus and cerebral cortex were similar to those in the sham group and in the LEV treatment group. The number of apoptotic cells decreased significantly in the LEV-treated group compared with the saline group.

Conclusions

These results show that LEV administration after hypoxia reduces neuronal apoptosis. Thus, we propose that LEV, as an effective antiepileptic and antiapoptotic drug, may be a viable choice for the control of seizure activity in neonates with HIBI.     

银杏叶提取物对宫内缺氧新生大鼠神经细胞凋亡的保护效应

目的探讨银杏叶提取物(EGb)对宫内缺氧新生大鼠急性脑缺血损伤的保护作用.方法夹闭妊娠大鼠子宫血管,制成急性脑缺血损伤新生鼠模型,治疗组给予腹腔注射EGb,在生后不同时间比较两组仔鼠脑组织含水量、NO的变化,神经型一氧化氮合酶(nNOS)的表达及神经细胞凋亡情况变化.结果急性脑缺血后,脑组织含水量明显增加,NO的含量迅速上升,同时凋亡细胞数增加,两者成直线正相关.EGb治疗后NO含量显著低于未治疗组,同时观察到治疗组的nNOS表达明显降低,凋亡细胞数量减少.结论EGb对急性缺血引起的脑损伤有保护作用.     

胰岛素对新生大鼠缺氧缺血性脑损伤保护作用的研究

目的探讨胰岛素对新生大鼠缺氧缺血性脑损伤(HIBD)的保护作用。方法建立新生大鼠HIE模型，利用末端转移酶介导的原位缺口标记法，检测缺氧缺血后24h大脑皮质和海马的神经元凋亡情况。结果大脑皮质和海马部位小、中剂量胰岛素组凋亡细胞显著少于对照组；大剂量胰岛素组凋亡细胞数显著多于对照组。侧脑室小剂量胰岛素组血糖水平与对照组无显著差异；中、大剂量胰岛素组血糖水平显著低于对照组。结论适量的胰岛素对新生大鼠HIBD具有保护作用。     

全身亚低温治疗新生儿缺氧缺血性脑病的疗效分析

目的探讨全身亚低温对新生儿缺氧缺血性脑病的近期和远期疗效。方法2002-08—2004-12郑州大学第三附属医院儿科收治的49例新生儿缺氧缺血性脑病患儿随机分为亚低温治疗组(24例)和对照组(25例),低温组在生后2～10h内给予全身亚低温治疗,维持肛温在(33～34)℃,持续72h,对照组在监护下维持肛温在(37·0±0·5)℃,两组急性期及恢复期其余治疗措施相同。通过对两组患儿不同时期神经学评分、新生儿神经行为测定及婴幼儿智能运动发育检测等来评价亚低温治疗新生儿缺氧缺血性脑病的远近期疗效。结果(1)神经学评分:两组患儿在治疗前神经学评分比较无明显统计学差异。但低温组在治疗12h、24h、48h、72h及80h的神经学评分均低于对照组,两组相比有统计学差异(P<0·05)。(2)神经行为测定:两组患儿分别在生后7d、14d和28d做NBNA检测,14d和28d的NBNA测定,低温组测定值明显高于对照组,P值均<0·05。(3)婴幼儿CD-CC智能发育评估:3个月、6个月、12个月、18个月时,低温组智能发育指数(MDI)和运动发育指数(PDI)均明显高于对照组,两组比较有显著性差异。结论全身亚低温治疗对新生儿缺氧缺血性脑病有明显的近期和远期神经保护作用。     

镁对缺氧缺血性脑损伤保护作用的研究

目的     

姜黄素对新生鼠高氧急性肺损伤作用的研究

目的 探讨姜黄素对新生大鼠高氧急性肺损伤的作用.方法 95％氧气3d制备新生大鼠高氧急性肺损伤模型,建模后将40只新生大鼠随机分为实验组[姜黄素灌胃,剂量为100 mg/(kg·d)]和对照组,每组20只.以20只正常新生大鼠作为空白组.在灌胃4d、7d后各组分别处死10只大鼠,取肺脏切片,检测肿瘤坏死因子(tumor necrosis factor,TNF)-α、白细胞介素(interleukin,IL)-Iβ及髓过氧化物酶( myeloperoxidase,MPO)含量.结果 实验组大鼠病理切片损伤均较对照组减轻.实验组大鼠4d及7d后TNF-α、IL-1β及MPO水平均明显低于对照组(P＜0.05);对照组大鼠4d、7d后TNF-α、IL-1β及MPO水平均高于空白组,差异有统计学意义(P＜0.01).结论 姜黄素对新生鼠高氧急性肺损伤可起保护作用.     

Neuroprotective effect of erythropoietin on hypoxic-ischemic brain injury in neonatal rats

Erythropoietin (Epo) prevents ischemia and hypoxia-induced neuronal death in vitro. Recent studies have shown that this cytokine also has in vivo neuroprotective effects in cerebral and spinal ischemia in adult rodents. In this study, we aimed to investigate the effect of systemically administered recombinant human Epo on infarct volume and apoptotic neuronal death in a newborn rat hypoxic-ischemic brain injury model. Our results showed that a single dose of intraperitoneal Epo treatment (1,000 U/kg) significantly decreased the mean infarct volume as compared to the control group. In contrast to the Epo-treated group, histopathological examination by positive terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling of the affected brain in control animals revealed widespread neuronal injury associated with numerous apoptotic cells. Morphometric analysis to determine the extent of damage quantitatively ascertained that the mean infarct volume was significantly lower in the Epo-treated group (p < 0.003). These results suggest the beneficial neuroprotective effect of Epo in this model of neonatal hypoxic-ischemic brain injury. To our knowledge, this is the first study that demonstrates a protective effect of Epo against hypoxia-ischemia in the developing brain.     

The sequelae of neonatal brain injury

The neonatal brain is very vulnerable to injury due to its relatively large size, rapid rate of development and immature immunological systems. Injury at this time often results in lifelong neuro-developmental sequelae such as cerebral palsy, learning difficulties and sensory deficits. In the term brain injury is most commonly due to hypoxia–ischaemia during labour, but hyperbilirubinaemia, trauma, thrombosis and infections remain important causes.In the preterm infant, because of immaturity, the pattern of injury is different with forms of white matter damage predominating. Germinal matrix haemorrhage, parenchymal infarction and forms of periventricular leucomalacia predominate. Preterm white matter damage often leads to altered or reduced development of cortical grey matter subsequently. All forms of cerebral palsy are seen in preterm children, but spastic cerebral diplegia is the commonest. Minor motor impairments in childhood are also very common as are behavioural disorders.Exact prognoses for infants with neonatal brain lesions are difficult to make owing to the fact that more than one lesion may co-exist in the same infant.