无创伤双后肢缺血后处理对移植胰腺缺血再灌注损伤的远隔保护

背景：缺血预处理及缺血后处理是近年来提出减轻缺血再灌注损伤有效方法。 目的：探讨无创伤双后肢缺血后处理对移植胰腺缺血再灌注损伤的影响及机制。 方法：18只糖尿病SD大鼠数字表法随机分为3组,对照组仅行开腹术;缺血再灌注组仅行胰腺移植;缺血后处理组,移植前行非创伤性双后肢缺血后处理。 结果与结论：缺血再灌注组血糖和胰腺组织中丙二醛水平均高于缺血后处理组(P < 0.01)、而超氧化物歧化酶活性低于缺血后处理组(P < 0.01);与缺血后处理组比较,缺血再灌注组胰腺组织凋亡指数明显增高(P < 0.01)。结果提示,无创伤双后肢缺血后处理对大鼠移植胰的缺血再灌注损伤具有保护作用,机制可能与可通过减少超氧化物歧化酶失活,从而清除氧自由基以及减少胰腺细胞凋亡等有关。     

脑缺血预处理对缺血再灌注损伤的保护作用

目的　观察缺血预处理对脑缺血再灌注损伤的保护作用。方法　采用四血管阻断法对实验鼠分组进行全脑缺血预处理及缺血后再灌注, 半定量法观察海马区神经元受损情况。结果　实验组四血管阻断３ 分钟（ 预处理） 后海马区神经元受损与对照组无显著差异;３ 天间隔６ 分钟全脑缺血再灌注组神经元受损较其他组明显减轻。结论　缺血预处理对脑缺血再灌注损伤保护作用与全脑缺血预处理时间, 后续全脑缺血再灌注损伤时间及两者间的时间间隔有关。     

细胞凋亡与肝移植缺血再灌注损伤

背景：肝脏缺血再灌注损伤是影响肝脏移植效果的重要因素,细胞凋亡是移植肝缺血再灌注损伤的重要机制之一。 目的：就近年来细胞凋亡与移植肝缺血再灌注损伤的研究做一综述,为抗细胞凋亡在减轻器官缺血再灌注损伤的临床应用提供参考依据。 方法：由第一作者检索1990/2010 PubMed数据库及中国期刊全文数据库有关细胞凋亡及器官移植缺血再灌注损伤的关系的文献,检索词为“apoptosis,organ transplantation,ischemia-reperfusion injury”。排除重复性研究。计算机初检得到339篇文献,最终纳入39篇文献进行下一步分析。 结果与结论：文章从肝脏移植缺血再灌注损伤中的细胞凋亡,移植肝缺血再灌注损伤中细胞凋亡发生的机制,移植肝缺血再灌注损伤中细胞凋亡的基因表达变化,抗凋亡治疗与防治肝移植缺血再灌注损伤几方面进行了叙述。细胞凋亡与移植肝缺血再灌注损伤有着密切的关系。而抑制细胞凋亡可以有效的减轻移植肝的缺血再灌注损伤,对提高移植物的存活率有着重要的意义。     

白藜芦醇对大鼠缺血再灌注损伤后脑组织的保护作用

目的探讨白藜芦醇对大鼠缺血再灌注损伤后脑组织的保护作用及其机制。方法利用线栓法制作大鼠脑缺血再灌注损伤模型。72只SD大鼠按随机数字表法随机平均分为假手术组、对照组、白藜芦醇高剂量组和白藜芦醇低剂量组。缺血2h再灌注24h后,分别测定动物的神经损伤功能评分、脑组织梗死体积,缺血再灌注损伤的脑组织中髓过氧化物酶(MPO)的活性、伊文思兰的含量、肿瘤坏死因子-α(TNF-α)的含量及基质金属蛋白酶-9(MMP-9)的表达水平。结果白藜芦醇治疗组神经功能损伤评分均较对照组明显降低(P<0.05),脑梗死体积明显缩小(P<0.05),MPO的活性、伊文思兰的含量、TNF-α的含量及MMP-9表达水平均也明显低于对照组(P<0.05)。结论白藜芦醇可能通过降低炎症反应和血脑屏障通透性对大鼠脑缺血再灌注损伤的脑组织起神经保护作用;其抗炎作用可能与其降低TNF-α的含量有关,而降低血脑屏障通透性则可能与MMP-9的表达下调有关。     

肝移植后缺血再灌注损伤大鼠诱导细胞凋亡中的一氧化氮

背景：由诱生型一氧化氮合酶产生的一氧化氮,是肝脏缺血再灌注损伤中病理生理学改变的一个重要因素。 目的：探讨一氧化氮在肝移植缺血再灌注诱导的肝细胞早期凋亡的影响以及相关基因caspase-3的表达情况。 方法：受体鼠72只随机数字表法均分成移植组、精氨酸组及L-硝基精氨酸甲酯组,均建立原位肝移植模型,后2组大鼠在开放血流前5 min于股静脉注射可升高血清一氧化氮水平的精氨酸或一氧化氮抑制剂L-硝基精氨酸甲酯。移植造模后剩余的24只大鼠设为假手术组。 结果与结论：血清谷草转氨酶活性比较,精氨酸组<移植组移植组>L-硝基精氨酸甲酯组;早期凋亡的高峰期为再灌注后3 h,肝细胞的活细胞数比例及肝组织中caspase-3的表达,精氨酸组<移植组< L-硝基精氨酸甲酯组。说明,一氧化氮对大鼠对肝移植缺血再灌注后肝细胞早期凋亡具有保护作用,且该作用可能主要通过下调caspase-3基因的表达。     

大蒜素对大鼠脊髓缺血再灌注损伤的保护作用

目的 研究大蒜素（allicin）在脊髓缺血再灌注损伤中的保护作用及其相关机制.方法 实验前1 w实验用SD大鼠预先给予不同浓度大蒜素腹腔注射,每天一次持续7d,采用肾下腹主动脉阻断法建立脊髓缺血再灌注损伤模型.损伤后24 h通过测定脊髓组织含水量、梗死体积和正常神经元计数评价大鼠脊髓组织损伤程度.采用（Basso-Beattie-Bresnahan,BBB）评分标准对大鼠进行后肢功能评分以反映损伤后运动功能.损伤后4h和24 h检测线粒体膜电位、活性氧自由基（ROS）含量和线粒体ATP的变化,讨论大蒜素保护作用与线粒体信号通路的关系.结果 大蒜素能减轻脊髓缺血再灌注损伤,促进运动功能恢复,抑制线粒体功能障碍.结论 大蒜素通过保护线粒体功能发挥对脊髓缺血再灌注损伤的保护作用.     

睾丸移植冷缺血时间与睾丸缺血再灌注损伤的关系

背景：睾丸移植是短时间热缺血损伤后快速进入冷缺血的过程,冷缺血时间的长短对睾丸生精功能是否存在影响目前还缺乏明确证据。 目的：模拟临床睾丸移植缺血再灌注兔模型,探索睾丸移植冷缺血时间与睾丸缺血再灌注损伤的相关性。 设计、时间及地点：分组设计,对比观察,于2006-05/12在武汉大学人民医院动物实验中心完成。 材料：雄性3~6月龄大白兔,体质量2.5~3.5 kg, 方法：采用自行设计的模拟临床睾丸移植过程的冷缺血灌注模型,对20只大白兔左侧的睾丸采用0~4 ℃ 高渗枸橼酸腺嘌呤液恒压灌注,并浸泡于0~4 ℃生理盐水中低温保存,于冷缺血后1,2,4,6 h开放左侧睾丸血流。术后24 h取双侧睾丸,以右侧睾丸作自身对照。 主要观察指标：苏木精-伊红染色及Johnsen评分判断睾丸损伤程度。丙二醛检测试剂盒检测每克睾丸组织中丙二醛含量。TUNEL法检测睾丸凋亡指数。 结果：冷缺血1 h后可见睾丸生精上皮结构稍紊乱,2 h后 生精上皮开始脱落,管腔内精子数量减少,4 h 后生精上皮明显变薄,仅见少量的精子细胞,6 h 后生精上皮仅可见少量精母细胞,部分呈唯Sertoli细胞表现。随冷缺血时间的延长,睾丸缺血再灌注损伤逐渐加重,Johnsen评分分值逐渐下降。睾丸组织冷缺血2 h后再灌注24 h的丙二醛水平明显高于自身对照组(P < 0.05),至4 h达到最高。凋亡细胞数量随冷缺血时间的延长逐渐增多,凋亡指数高于自身对照(P < 0.05)。 结论：冷缺血后4h再灌注会造成睾丸生精上皮的严重损害,提示睾丸移植前冷缺血时间应当控制在4 h以内。     

缺血后处理对大鼠脑缺血再灌注损伤神经保护作用的研究

目的探讨大鼠脑缺血后处理对缺血再灌注损伤后神经元的保护作用。方法健康雄性SD大鼠30只,随机分为假手术组(SO组)、缺血再灌注对照组(MCAO组)、缺血后处理组(IPOC组)3组。采用线栓法制备大鼠MCAO模型及IPOC模型,分别用TTC染色法计算脑梗死体积、流式细胞术和ELISA法观察,对于大鼠缺血半暗带神经细胞凋亡率及血清神经元特异性烯醇化酶(NSE)含量的影响。结果 (1)大鼠脑缺血再灌注后24h,IPOC组较MCAO组梗死体积明显减小(P<0.05);(2)MCAO组大鼠脑缺血再灌注24h细胞凋亡发生率及血清中NSE的含量较SO组显著增加(P<0.01);(3)IPOC组神经元凋亡发生率及血清NSE较MCAO组显著降低(P<0.05或0.01)。结论大鼠脑缺血后处理对缺血再灌注神经元损伤有保护作用。     

肾上腺髓质素对骨骼肌缺血再灌注损伤的影响

背景：作为一种新发现的内分泌激素,研究表明肾上腺髓质素能在多种重要器官的缺血再灌注损伤中起到保护作用,是否能对骨骼肌缺血再灌注有保护作用有待研究。 目的：观察肾上腺髓质素对大鼠骨骼肌缺血再灌注损伤的影响。 设计、时间及地点：随机对照动物实验,于2007-03/07在湖南师范大学医学院机能实验室、分子生物学实验室完成。 材料：健康雄性SD大鼠30只,随机分为对照组,缺血再灌注组,0.1,0.5,1.0 nmol/kg肾上腺髓质素处理组,每组6只。 方法：无创动脉夹夹闭右侧股动脉4 h,再灌注3 h,建立后肢骨骼肌缺血再灌注损伤模型。对照组仅暴露出股动静脉,不做血管夹闭和环扎。肢体再灌注前肾上腺髓质素处理组分别自尾静脉注射0.1,0.5,1.0 nmol/kg肾上腺髓质素生理盐水溶液,对照组及缺血再灌注组注射等量生理盐水。 主要观察指标：测定各组血清肌酸激酶、乳酸脱氢酶活性;取术侧腓肠肌,测定组织中超氧化物歧化酶、髓过氧化物酶的活性、丙二醛水平并观察骨骼肌组织形态学变化。 结果：30只大鼠均进入结果分析。①与对照组比较,缺血再灌注组肌酸激酶、乳酸脱氢酶、丙二醛、髓过氧化物酶值增高(P < 0.01),超氧化物歧化酶值降低(P < 0.01);腓肠肌超微结构损伤明显加重。②与缺血再灌注组比较,肾上腺髓质素处理组肌酸激酶、乳酸脱氢酶、丙二醛、髓过氧化物酶值减低,超氧化物歧化酶值增高。0.1 nmol/kg肾上腺髓质素处理组与缺血再灌注组比较,肌酸激酶、丙二醛的变化无统计学意义(P > 0.05),其他均有统计学意义(P < 0.05~0.01)。③0.5 nmol/kg肾上腺髓质素处理组肌酸激酶、髓过氧化物酶、丙二醛值低于0.1 nmol/kg肾上腺髓质素处理组(P < 0.05),1.0 nmol/kg肾上腺髓质素处理组肌酸激酶值低于0.1 nmol/kg肾上腺髓质素处理组(P < 0.05)。0.1 nmol/kg肾上腺髓质素处理组腓肠肌超微结构损伤相对加重。 结论：肾上腺髓质素可减轻缺血再灌注对骨骼肌造成的损伤,对缺血再灌注骨骼肌具有保护作用。     

高血压大鼠脑缺血再灌注损伤时的病理学变化

目的 研究高血压大鼠在脑缺血损伤时的病理改变.方法 用线拴法将肾性高血压大鼠制作成脑缺血再灌注模型,在光镜和透射电镜下观察脑组织的病理和超微结构改变.结果 高血压组大鼠与正常大鼠相比,在局灶性缺血再灌注损伤时有明显的组织学改变.结论 高血压可经过多种机制加剧脑缺血性损伤.     

肝动脉/门静脉早期复流对肝移植大鼠小肠缺血再灌注损伤的影响

背景：当肝动脉与门静脉早期复流时序不同时,是否会加重对肝移植大鼠小肠缺血/再灌注的损伤尚未见大量报道。 目的：探讨肝动脉与门静脉早期复流对肝移植大鼠小肠缺血/再灌注损伤的影响。 方法：采用门静脉灌注的大鼠自体肝移植模型,78只SD大鼠以简单随机化法分为3组：肝动脉组(n=36)：行自体肝移植手术,以40C乳酸林格液由门静脉灌肝40 min,开放肝动脉及下腔静脉,10 min后开放门静脉;门静脉组(n=36)：行自体肝移植手术,门静脉开放恢复肝脏血流后10 min再开放肝动脉血流;假手术组(n=6)：打开腹腔,游离肝脏后关腹。观察各组小肠显微及超微结构变化并测定一氧化氮水平。 结果与结论：术后各实验组不同时段先后出现小肠绒毛排列不整或紊乱,小肠黏膜细胞线粒体大小不一,明显肿胀,呈类圆形,内有空泡变性,严重者可见嵴减少、断裂或消失。小肠组织一氧化氮水平均升高。上述变化在术后12 h达高峰。术后肝动脉先复流组小肠显微及超微结构损伤及小肠组织一氧化氮水平明显高于门静脉先复流组。提示,肝动脉早期复流可以通过早期肝脏供氧以减少移植肝脏的损害,但门静脉的延迟开放则加重了肝移植大鼠小肠的缺血/再灌注损伤。     

Triptolide for cerebral ischemia/reperfusion injury

BACKGROUND: Studies have demonstrated that triptolide has good anti-inflammatory and immunosuppressive effects. However, the effect of triptolide on cerebral ischemia/reperfusion injury is still unclear. OBJECTIVE: To observe the effects of triptolide on neurologic function, infarct volume, water content of brain tissue, neutrophil number in microvascular wall and interleukin-1β(IL-1β) expression in rat models of local ischemia/reperfusion, and analyze the mechanism of triptolide for protecting brain. DESIGN: Randomized controlled experiment. SETTING: Department of Pathology, Medical School of Ningbo University; Department of Forensic Medicine, Tongji Medical College of Huazhong University of Science and Technology. MATERIALS: Sixty Wistar rats of either gender, aged 4 months old, weighing from 200 to 250 g, were provided by the Experimental Animal Center, Tongji Medical College, Huazhong University of Science and Technology. Triptolide was purchased from Fujian Institute for Medical Science (purity 99.98%; Batch No. 2000215). It was dissolved in 20 g/L propanediol, and filtered with 200-mesh filter for later use. METHODS: This experiment was carried out in the laboratory of Forensic Medicine, Tongji Medical College of Huazhong University of Science and Technology, Department of Pathology, Medical School of Ningbo University between January 2001 and September 2004. ① Sixty Wistar rats were randomized into 4 groups: sham-operation group, model group, low-dose triptolide group and high-dose triptolide group. Rats in each group, except for sham-operation group, were developed into rat models of cerebral ischemia/reperfusion according to the method of Longa et al. In the first 3 days of modeling, rats in the low- and high-dose triptolide groups were intraperitoneally injected with 0.2 and 0.4 mg/kg triptolide respectively, once a day, 3 days in total. ② At ischemia 1 hour and reperfusion 24 hours, infarct volume, neurologic deficit (five-point scale, higher scores indicated poor neurologic function), water content of brain tissue, neutrophil number in microvascular wall in the middle cerebral artery occlusive side of rats were detected, meanwhile, brain tissue injury degree and IL-1βimmunohistochemical staining changes in brain-derived nerve cells were observed under the optical microscope. MAIN OUTCOME MEASURES: Neurologic deficit, infarct volume percentage, water content of brain tissue, neutrophil number in microvascular wall and positive rate of IL-1β immunoreaction. RESULTS: Sixty rats were all involved in the final analysis. ① Neurologic deficit scores of rats in the low- and high-dose triptolide groups were （1.96±0.14） and （1.75±0.16）points respectively , which were both significantly lower than those in model group [（2.58±0.11）points，P < 0.05，0.01]. ② Infarct volume percentages of rats in low- and high-dose triptolide groups were significantly lower than that in model group separately (P < 0.05, 0.01). ③Water content of brain tissue of rats in model group was significantly higher than that in the sham-operation group [（82.35±1.26）% vs. （76.65±1.17）%，P < 0.01]; Water content of brain tissue of rats in the low- and high-dose triptolide groups was respectively（80.15±1.43）%，（78.23± 1.15）%, which was significantly lower than that in the model group (P < 0.05, 0.01). ④Pathological changes of brain tissue of rats: Under the optical microscope, infarct focus was not found in the brain tissue of rats in the sham-operation group, while clear infarct focus could be found in the brain tissue of rats in the model group; Although infarct focus was found in the brain tissue of rats in the low- and high-dose triptolide groups, the whole infarct area was contracted as compared as that in the model group. ⑤Neutrophil number in microvascular wall of brain tissue of rats in the low- and high dose triptolide groups was 10.60±2.12，8.11±1.21 respectively, which was significantly less than that in model group（16.25±1.96，P < 0.05，0.01）. ⑥Positive rate of IL-1βimmunoreaction in the brain tissue of rats in model group was significantly higher than that in the sham-operation group (P < 0.01); and positive rate of IL-1β immunoreaction in the brain tissue of rats in low- and high-dose triptolide groups was significantly lower than that in the model group (P < 0.05, 0.01), but higher than that in the sham-operation group, without significant difference (P > 0.05). CONCLUSION: Triptolide protects against cerebral ischemia/reperfusion injury of rats that may be related with anti-inflammations. Triptolide inhibits IL-1β expression in brain tissue and reduces the attachment and aggregation of neutrophils in blood capillary, and further inhibits the infiltration of blood white cells, thus, it will lessen cerebral injury, contract cerebral infarct and improve cerebral function.     

Protective effects of acupuncture on brain tissue following ischemia/reperfusion injury★

BACKGROUND： In patients with cerebrovascular disease, by means of the neuroendocrine system, acupuncture supports the transformation of a local pathological status into a physiological status. Recently, great progress has been made in studying the protective effects of acupuncture on brain ischemia/reperfusion injury. OBJECTIVE： To summarize research advances in the protective effects of acupuncture on brain ischemia/reperfusion injury. RETRIEVAL STRATEGY： Using the terms ＂acupuncture, transcutaneous electrical acupoint stimulation, cerebral ischemia/reperfusion injury, and cerebral protection＂, we retrieved articles from the PubMed database published between January 1991 and June 1994. Meanwhile, we searched the China National Knowledge Infrastructure with the same terms. Altogether, 114 articles and their results were analyzed. Inclusive criteria： studies that were closely related to the protective effects of acupuncture on brain ischemia/reperfusion injury, or studies, whose contents were in the same study field and were published recently, or in the authorized journals. Exclusive criteria： repetitive studies. LITERATURE EVALUATION： Thirty articles that related to the protective effects of acupuncture on brain ischemia/reperfusion injury were included. Among them, 7 were clinical studies, and the remaining 23 articles were animal experimental studies. DATA SYNTHESIS： ① Animal experimental studies have demonstrated that acupuncture improves brain blood perfusion and brain electrical activity, influences pathomorphological and ultramicrostructural changes in ischemic brain tissue, is beneficial in maintaining the stability of intracellular and extracellular ions, resists free radical injury and lipid peroxidation, and influences cytokine, neurotransmitter, brain cell signal transduction, and apoptosis-regulating genes. ② Clinical studies have demonstrated that acupuncture not only promotes nutritional supply to local brain tissue in patients with cerebral infarction, but also increases brai     

SP600125对大鼠肝缺血再灌注损伤的保护作用

背景：SP600125作为JNK激酶抑制剂,可特异性阻断JNK细胞转导通路,对肝脏缺血再灌注又起到怎样的作用,目前尚无相关研究。 目的：应用SP600125对肝脏缺血再灌注进行干预,分析JNK信号转导通路在该病理生理过程中的作用。 方法：将30只雄性SD大鼠按随机数字表法分为3组,假手术组、缺血再灌注组及SP600125组各10只。假手术组仅行进腹手术;缺血再灌注组行进腹手术,阻断肝左中叶的血供;SP600125组于术前半小时腹腔注射SP600125 15 mg/kg,其他操作同缺血再灌注组。于复灌后2 h取材,分别测定各组血清肝功能酶活性,通过苏木精-伊红切片染色观察肝组织结构的病理变化,运用免疫组织化学法检测肝组织中p-JNK表达并进行半定量分析,以比色法检测肝脏丙二醛含量及髓过氧化物酶活性。 结果与结论：相对于缺血再灌注组,SP600125组血清肝功能酶活性明显下降,肝脏p-JNK表达较低,肝脏髓过氧化物酶活性以及丙二醛含量下降,病理损伤有所缓解。提示JNK细胞信号转导通路在肝缺血再灌注损伤过程中被广泛激活,应用JNK抑制剂SP600125对缺血再灌注损伤有保护作用。     

E不同冷保存时间热缺血供肝在肝移植中的应用**☆

背景：目前国内临床肝移植供肝的主要来源仍然是无心跳供体供肝,国外近年来也越来越多地使用无心跳供体供肝,但无心跳供体供肝这类经历了热缺血的供肝能够耐受冷保存的安全时限尚没有统一标准,也鲜有这方面的临床报道。 目的：评价不同冷保存时间的热缺血供肝在临床肝移植中的应用安全性及疗效。 设计、时间及地点：随机对照观察,于2006-01/2007-12在中山大学附属第一医院器官移植中心完成。 对象：无心跳供体供肝热缺血时间在10 min内的肝移植病例154例。 方法：根据冷保存时间不同分为3组,8 h内组58例,8~12 h组62例,13~16 h组34例。供肝按供体分配原则按随机数字表法分配给3组患者,移植后采用相同的免疫抑制方案。 主要观察指标：比较3组患者肝移植后谷丙转氨酶峰值、原发性移植肝无功能、急性排斥反应、胆道并发症、血管并发症、感染,以及移植肝存活和受体存活情况的差异。 结果：随访8~32个月,3组患者移植后均未发生原发性移植肝无功能。8~12 h组患者移植后仅谷丙转氨酶峰值高于8 h内组(P < 0.05),其余治疗两组比较差异均无显著性意义(P > 0.05)。与8 h内组患者比较,13~16 h组患者的移植后谷丙转氨酶峰值、感染发生率和胆道并发症发生率显著升高(P < 0.05),移植肝存活率和受体存活率显著降低(P < 0.05)。 结论：热缺血时间在10 min内的无心跳供体供肝能够耐受12 h的冷保存损伤,超过此时限,移植后胆道并发症和感染的发生率明显升高,移植肝存活率和受体存活率明显降低。     

Triptolide for cerebral ischemia/reperfusion injuryt

BackgroundStudies have demonstrated that triptolide has good anti-inflammatory and immunosuppressive effects. However, the effect of triptolide on cerebral ischemia/reperfusion injury is still unclear.ObjectiveTo observe the effects of triptolide on neurologic function, infarct volume, water content of brain tissue, neutrophil number in microvascular wall and interleukin-1β(IL-1β) expression in rat models of local ischemia/reperfusion, and analyze the mechanism of triptolide for protecting brain.DesignRandomized controlled experiment.SettingDepartment of Pathology, Medical School of Ningbo University; Department of Forensic Medicine, Tongji Medical College of Huazhong University of Science and Technology.MaterialsSixty Wistar rats of either gender, aged 4 months old, weighing from 200 to 250 g, were provided by the Experimental Animal Center, Tongji Medical College, Huazhong University of Science and Technology. Triptolide was purchased from Fujian Institute for Medical Science (purity 99.98%; Batch No. 2000215). It was dissolved in 20 g/L propanediol, and filtered with 200-mesh filter for later use.MethodsThis experiment was carried out in the laboratory of Forensic Medicine, Tongji Medical College of Huazhong University of Science and Technology, Department of Pathology, Medical School of Ningbo University between January 2001 and September 2004.

Sixty Wistar rats were randomized into 4 groups: sham-operation group, model group, low-dose triptolide group and high-dose triptolide group. Rats in each group, except for sham-operation group, were developed into rat models of cerebral ischemia/reperfusion according to the method of Longa et al. In the first 3 days of modeling, rats in the low- and high-dose triptolide groups were intraperitoneally injected with 0.2 and 0.4 mg/kg triptolide respectively, once a day, 3 days in total.

At ischemia 1 hour and reperfusion 24 hours, infarct volume, neurologic deficit (five-point scale, higher scores indicated poor neurologic function), water content of brain tissue, neutrophil number in microvascular wall in the middle cerebral artery occlusive side of rats were detected, meanwhile, brain tissue injury degree and IL-1βimmunohistochemical staining changes in brain-derived nerve cells were observed under the optical microscope.Main outcome measuresNeurologic deficit, infarct volume percentage, water content of brain tissue, neutrophil number in microvascular wall and positive rate of IL-1β immunoreaction.ResultsSixty rats were all involved in the final analysis.

Neurologic deficit scores of rats in the low- and high-dose triptolide groups were (1.96±0.14) and (1.75±0.16)points respectively, which were both significantly lower than those in model group [(2.58±0.11)points,P < 0.05,0.01].

Infarct volume percentages of rats in low- and high-dose triptolide groups were significantly lower than that in model group separately (P < 0.05, 0.01).

Water content of brain tissue of rats in model group was significantly higher than that in the sham-operation group [(82.35±1.26)% vs. (76.65±1.17)%,P < 0.01]; Water content of brain tissue of rats in the low- and high-dose triptolide groups was respectively(80.15±1.43)%,(78.23± 1.15)%, which was significantly lower than that in the model group (P < 0.05, 0.01).

Pathological changes of brain tissue of rats: Under the optical microscope, infarct focus was not found in the brain tissue of rats in the sham-operation group, while clear infarct focus could be found in the brain tissue of rats in the model group; Although infarct focus was found in the brain tissue of rats in the low- and high-dose triptolide groups, the whole infarct area was contracted as compared as that in the model group.

Neutrophil number in microvascular wall of brain tissue of rats in the low- and high dose triptolide groups was 10.60±2.12,8.11±1.21 respectively, which was significantly less than that in model group(16.25±1.96,P < 0.05,0.01).

Positive rate of IL-1βimmunoreaction in the brain tissue of rats in model group was significantly higher than that in the sham-operation group (P < 0.01); and positive rate of IL-1β immunoreaction in the brain tissue of rats in low- and high-dose triptolide groups was significantly lower than that in the model group (P < 0.05, 0.01), but higher than that in the sham-operation group, without significant difference (P > 0.05).ConclusionTriptolide protects against cerebral ischemia/reperfusion injury of rats that may be related with anti-inflammations. Triptolide inhibits IL-1β expression in brain tissue and reduces the attachment and aggregation of neutrophils in blood capillary, and further inhibits the infiltration of blood white cells, thus, it will lessen cerebral injury, contract cerebral infarct and improve cerebral function.     

Ginsenoside Rd inhibits apoptosis following spinal cord ischemia/reperfusion injury

Ginsenoside Rd has a clear neuroprotective effect against ischemic stroke. We aimed to verify the neuroprotective effect of ginsenoside Rd in spinal cord ischemia/reperfusion injury and explore its anti-apoptotic mechanisms. We established a spinal cord ischemia/reperfusion injury model in rats through the occlusion of the abdominal aorta below the level of the renal artery for 1 hour. Successfully established models were injected intraperitoneally with 6.25, 12.5, 25 or 50 mg/kg per day ginsenoside Rd. Spinal cord morphology was observed at 1, 3, 5 and 7 days after spinal cord ischemia/reperfusion injury. Intraperitoneal injection of ginsenoside Rd in ischemia/reperfusion injury rats not only improved hindlimb motor function and the morphology of motor neurons in the anterior horn of the spinal cord, but it also reduced neuronal apoptosis. The optimal dose of ginsenoside Rd was 25 mg/kg per day and the optimal time point was 5 days after ischemia/ reperfusion. Immunohistochemistry and western blot analysis showed ginsenoside Rd dose-de- pendently inhibited expression of pro-apoptotic Caspase 3 and down-regulated the expression of the apoptotic proteins ASK1 and JNK in the spinal cord of rats with spinal cord ischemia/reper- fusion injury. These findings indicate that ginsenoside Rd exerts neuroprotective effects against spinal cord ischemia/reperfusion injury and the underlying mechanisms are achieved through the inhibition of ASK1-JNK pathway and the down-regulation of Caspase 3 expression.     

Dose-dependent effects of procyanidin on nerve growth factor expression following cerebral ischemia/ reperfusion injury in rats★

BACKGROUND： Recently, grape seed procyanidin （GSP） has been shown to be exhibit antioxidant effects, effectively reducing ischemia/reperfusion injury and inhibiting brain cell apoptosis. OBJECTIVE： To study the effects of GSP on nerve growth factor （NGF） expression and neurological function following cerebral ischemia/reperfusion injury in rats. DESIGN： Randomized controlled study based on SD rats. SETTING： Weifang Municipal People＇s Hospital. MATERIALS： Forty-eight healthy adult SD rats weighing 280-330 g and irrespective of gender were provided by the Experimental Animal Center of Shandong University. GSP derived from grape seed was a new high-effective antioxidant provided by Tianjin Jianfeng Natural Product Researching Company （batch number： 20060107）. Rabbit-anti-rat NGF monoclonal antibody was provided by Beijing Zhongshan Biotechnology Co., Ltd., and SABC immunohistochemical staining kit by Wuhan Boster Bioengineering Co., Ltd. METHODS： The present study was performed in the Functional Laboratory of Weifang Medical College from April 2006 to January 2007. Forty-eight SD rats were randomly divided into the sham operation group, ischemia/reperfusion group, high-dose GSP （40 mg/kg） group, or low-dose GSP （10 mg/kg） group （n = 12 per group）. Ischemia/reperfusion injury was established using the threading embolism method of the middle cerebral artery. Rats in the ischemia/reperfusion model group were given saline injection （2 mL/kg i.p.） once daily for seven days pre-ischemia/reperfusion, and once more at 15 minutes before reperfusion. Rats in the high-dose and low-dose GSP groups were injected with GSP （20 or 5 mg/mL i.p., respectively, 2 mL/kg） with the same regime as the ischemia/reperfusion model group. The surgical procedures in the sham operation group were as the same as those in the ischemia/reperfusion model group, but the thread was approximately 10 mm long, thus, the middle cerebral artery was not blocked. MAIN OUTCOME MEASURES： NGF expression in the