甘草总黄酮对大鼠局灶性脑缺血再灌注损害的脑保护作用

目的 研究甘草总黄酮对大鼠局灶性脑缺血再灌注损害的脑保护作用。方法 我们拟采用线栓法建立的大鼠大脑中动脉（MCA）缺血再灌注模型。并用3种不同剂量的甘草总黄酮灌服后，测定缺血2h再灌注24h时血清和脑组织中丙二醛（MDA），超氧化物歧化酶（SOD），一氧化氮（NO），一氧化碳合酶（NOS）活性。结果 发现甘草总黄酮能促进大鼠MCA，缺血再灌注24h后神经功能恢复，甘草总黄酮能明显降低血清，脑组织中的MDA，NO含量，提高体内SOD的活性。结论 提示中药甘草总黄酮有抗氧化作用。     

依达拉奉对脑缺血再灌注大鼠脑组织及血清超氧化物歧化酶、一氧化氮、丙二醛水平的影响

目的探讨依达拉奉对局灶性脑缺血再灌注损伤的影响。方法将SD大鼠分为假手术组,脑缺血再灌注组和依达拉奉干预组(干预组),采用线栓法制备大脑中动脉缺血再灌注模型;缺血1h后,设再灌注2h、6h、12h、24h组,采用化学比色法检测各组脑组织及血清超氧化物歧化酶(SOD)、一氧化氮(NO)、丙二醛(MDA)浓度。结果缺血再灌注组脑组织SOD下降,血清SOD先升后降;脑组织NO浓度先降后升,血清NO浓度持续升高;脑组织及血清MDA浓度均先升后降;与缺血再灌注组比,干预组SOD下降幅度小(均P<0·01),NO、MDA浓度明显降低;干预组6h、12h脑组织含水量明显低于缺血再灌注组(均P<0·01)。结论依达拉奉可降低羟自由基水平,对脑缺血再灌注损伤有保护作用。     

山楂总黄酮对实验性脑缺血再灌注损伤大鼠的保护作用

目的 研究山楂总黄酮（HFs）对实验性脑缺血再灌注损伤大鼠的保护作用.方法 SD雄性大鼠90只随机分为5组,各组按规定预防给药15 d后,按照Longa法制作大脑中动脉闭塞模型,假手术组除不插入栓线外其余相同,缺血2 h后再灌注.分别于再灌注3 h、24 h进行神经行为评分;再灌注24 h后断头取梗死侧大脑皮质匀浆,测定丙二醛（MDA）、一氧化氮（NO）含量及超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、一氧化氮合成酶（NOS）、诱导型一氧化氮合成酶（iNO）活性.结果 山楂总黄酮各剂量组再灌注3 h、24 h神经行为评分明显低于缺血再灌注组;与I/R组比较,再灌注24 h后,山楂总黄酮各剂量组缺血梗死侧大脑皮质丙二醛（MDA）、一氧化氮（NO）含量明显降低,超氧化物歧化酶（SOD）、过氧化氢酶（CAT）活性升高,一氧化氮合成酶（NOS）、诱导型一氧化氮合成酶（iNO）活性也明显低于I/R组,各组间差异有统计学意义.结论 山楂总黄酮对实验性脑缺血再灌注损伤大鼠有一定的保护作用,其作用机制可能与提高脑组织中SOD和CAT活性、抑制脂质过氧化及炎症反应有关.     

尼莫地平对大鼠急性脑缺血再灌注损伤早期保护作用的研究

目的探讨尼莫地平对急性脑缺血再灌注损伤的早期保护作用。方法线栓法复制大鼠急性脑缺血模型。30只雄性Wistar大鼠随机分为假手术、模型、尼莫地平3组。模型组采取缺血2h再灌注2h。尼莫地平组大鼠在缺血0时刻起每小时腹腔注射给药一次,剂量为5mg/kg。各组大鼠在手术4h后实验结束后,行腹主动脉采血,同时取完整脑组织。脑组织切片进行TTC染色,并比较各组脑组织梗死面积。检测各组大鼠血清及脑组织匀浆中SOD、MDA、NO含量。结果与模型组相比,尼莫地平组大鼠脑组织梗死面积显著减少。血清生化指标显示,模型组SOD含量显著低于假手术组,给予尼莫地平治疗后,SOD含量增加明显。模型组MDA、NO含量明显高于假手术组,尼莫地平组明显降低血清中MDA、NO。结论尼莫地平对大鼠急性脑缺血再灌注损伤有保护作用,这种保护作用与NO和氧化应激密切相关。     

实验性高血糖大鼠缺血脑组织一氧化氮和中性白细胞浸润的变化

目的　探讨高血糖在缺血再灌注脑损伤中的作用。　　方法　利用链尿酶素诱发大鼠发生高血糖 ,以线栓法复制大鼠大脑中动脉区缺血再灌注模型 ,研究该条件下脑组织损伤、中性白细胞浸润和一氧化氮 (NO)含量变化与血糖的关系。　　结果　高血糖组脑缺血再灌注 1 2h、2 4h和 48h时脑梗死体积、缺血脑组织中性白细胞浸润程度 (MPO活性 )及NO含量均显著高于正常血糖组。　　结论　高血糖加重大鼠脑缺血再灌注损伤 ,其葡萄糖毒性作用机制可能是通过缺血脑组织内中性白细胞和NO的致伤作用实现的。     

PPARγ激动剂对大鼠局灶性脑缺血再灌注损伤的保护作用

目的观察PPARγ激动剂对大鼠局灶性脑缺血再灌注损伤(I/R)的保护作用,并对其作用机制进行初步探讨。方法复制大鼠大脑中动脉阻塞再灌注模型(MCAO/R),分别采用TTC染色法、神经功能缺损评分法观察PPARγ激动剂对大鼠脑梗死体积和行为学评分的影响,同时观察PPARγ激动剂对脑组织形态学和丙二醛(MDA)水平、超氧化物歧化酶(SOD)活性、诱导型一氧化氮合酶(iNOS)活化和一氧化氮(NO)含量的影响。结果PPARγ激动剂能够降低I/R大鼠脑梗死体积和行为学评分,减轻受损大鼠皮层脑组织的病理改变,抑制脑组织中MDA的生成、提高SOD的活性、抑制iNOS活性、降低NO含量。结论PPARγ激动剂对大鼠脑缺血再灌注损伤有一定保护作用,其作用机制与增强SOD活性,抑制脑组织中iNOS活性、降低NO和MDA含量及减轻I/R中氧化损伤有关。     

托吡酯对大鼠脑缺血再灌注后血清超氧化物歧化酶活性、丙二醛含量及神经功能的影响

目的探讨托吡酯(TPM)对大鼠脑缺血再灌注后血清超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量和神经功能的影响。方法将SD大鼠随机分为缺血再灌注组、TPM组及假手术组;采用线栓法建立大鼠大脑中动脉闭塞模型,TPM组动物分别于插线和再灌注时腹腔注射TPM混悬液(8mg/ml,80mg/kg);各组术后24h时进行神经功能评分后处死动物。采用羟胺氧化法测定血清SOD活性及硫代巴比妥酸法测定血清MDA含量。结果血清SOD活性及MDA含量缺血再灌注组分别为(157.72±19.04)U/ml及(7.45±0.84)nmol/ml,TPM组分别为(171.25±15.72)U/ml及(6.10±0.98)nmol/ml,假手术组分别为(179.74±7.95)U/ml及(5.90±0.72)nmol/ml;与TPM组及假手术组相比,缺血再灌注组大鼠血清SOD活性明显降低,MDA含量明显升高(均P<0.05)。TPM组及假手术组间血清SOD活性和MDA含量差异无显著性。TPM组神经功能评分较缺血再灌注组有显著改善(P<0.05)。结论TPM能减少脑缺血再灌注大鼠脑组织中抗氧化酶的消耗,有效抑制氧自由基的产生及其毒性,具有减轻脑缺血神经功能障碍的作用。     

EGb761对大鼠局灶性脑缺血再灌注损伤的保护作用

目的 :观察 EGb76 1对大鼠局灶性脑缺血再灌注损伤的保护作用。方法 :45只大鼠随机分为假手术组 (A组 ) ,脑缺血再灌注损伤组 (B组 ) ,EGb76 1治疗组 (C组 ) ,每组 15只。以线栓法制作大鼠脑缺血再灌注损伤模型。每组 10只缺血 6 0 min再灌注 6 0 min后断头处死 ,取脑测定 NO、NOS、MDA和 SOD变化 ,其余 5只缺血 3h再灌注 2 4h后断头处死 ,观察常规病理、Niss小体及凋亡细胞变化。C组于实验前 3天开始灌胃给 EGb76 1(15 0 mg/ kg,每日 2次 ,术前 1h、术后 12 h灌 EGb76 115 0 mg/ kg)。结果 :脑缺血再灌注后 ,B组 NO、MDA含量 ,NOS活性较 A组升高 ,SOD活性降低 (P<0 .0 5 ) ,病理变化明显 ,凋亡细胞增多。C组 NO、MDA含量及 NOS活性降低 ,SOD活性升高 (P<0 .0 5 ) ,C组病理变化减轻 ,凋亡细胞减少 (P<0 .0 5 )。结论 :EGb76 1对大鼠局灶性脑缺血再灌注损伤具有保护作用。     

高渗氯化钠羟乙基淀粉40在大鼠脑缺血-再灌注损伤中的抗氧化作用

目的探讨高渗氯化钠羟乙基淀粉40(HH40)注射液在大鼠脑缺血-再灌注(I/R)损伤中的抗氧化作用。方法 24只雄性SD大鼠随机分为假手术组、模型组(B组)、HH40低剂量组(C组)、HH40高剂量组(D组)。大脑中动脉线栓法制备大鼠局灶性脑I/R损伤模型,制模成功后50min,舌下静脉输注HH40。再灌注24h后,腹腔静脉取血并分离血清,断头取脑,检测缺血区脑组织匀浆中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)的活性、丙二醛(MDA)的含量及血清GSH-Px的活性。结果与假手术组比较,模型组脑组织MDA含量升高、SOD活性降低,血清和脑组织GSH-Px活性下降。与模型组比较,HH40低剂量及高剂量组脑组织MDA含量降低、SOD及GSH-Px活性升高。结论 HH40能提高大鼠脑I/R的抗氧化作用、增强氧自由基的清除。     

二烯丙基硫醚对大鼠脑缺血再灌注损伤后Nrf2、NQ01表达的影响

目的 探讨二烯丙基硫醚对大鼠局灶性脑缺血再灌注损伤后Nrf2、NQ01表达的影响.方法 实验动物随机分为假手术组、缺血再灌注组、200mg/kg二烯丙基硫醚预处理组.采用线栓法制备大鼠大脑中动脉缺血再灌注模型,缺血2h再灌注24h后进行神经行为学评分,测定脑梗死体积及脑组织中SOD、MDA活性,采用免疫荧光和Western Blot测定Nrf2、NQ01蛋白分子的表达.结果 与缺血再灌注组相比,大鼠经二烯丙基硫醚预处理后神经损害症状减轻,脑梗死体积缩小,SOD活性增强,同时MDA活性受到抑制,Nrf2、NQ01I蛋白分子表达上调.结论 二烯丙基硫醚对大鼠脑缺血再灌注损伤具有一定的神经保护作用,可能与其增强大鼠脑组织抗氧化酶活性和激活Nrf2/NQ01通路有关.     

Effects of transection of cervical sympathetic trunk on cerebral infarct volume and oxygen free radical levels in rats with focal cerebral ischemia/reperfusion injury

BACKGROUND: Stellate ganglion block (SGB) plays a protective role on the brain, but the precise mechanism of action is not clear.OBJECTIVE: To simulate SGB by transection of the cervical sympathetic trunk (TCST) and to investigate the TCST effects on changes in cerebral infarct volume and oxygen free radical levels in rats with focal cerebral ischemia/reperfusion injury.DESIGN, TIME AND SETTING: A complete randomized control animal experiment was performed at the Institute of Neurological Diseases of Taihe Hospital, Yunyang Medical College from February to December 2005.MATERIALS: A total of 101 healthy Wistar rats, weighing 280-320g, of both genders, aged 17-18 weeks, were used in this study. 2,3,5-triphenyltetrazolium chloride (TTC) was purchased from Changsha Hongyuan Biological Company. Superoxide dismutase (SOD), malondialdehyde (MDA) and nitric oxide (NO) assay kits were provided by Nanjing Jiancheng Bioengineering Institute.METHODS: Rats were randomly divided into a TCST group, a model group and a sham operation group. Successful models were included in the final analysis, with at least 20 rats in each group. After TCST, rat models of focal cerebral ischemia/reperfusion injury were established in the TCST group by receiving middle cerebral artery occlusion (MCAO) by the intraluminal suture method for 2 hours, followed by 24 hours of reperfusion. Rat models of focal cerebral ischemia/reperfusion injury were made in the model group. Rats in the sham operation group underwent experimental procedures as for the model group, threading depth of 10mm, and middle cerebral artery was not ligated.MAIN OUTCOME MEASURES: Brain tissue sections of ten rats from each group were used to measure cerebral infarct volume by TTC staining. Brain tissue homogenate of another ten rats from each group was used to detect SOD activities, MDA contents and NO levels. Rat neurological function was assessed by neurobehavioral measures.RESULTS: Cerebral infarct volume was bigger in the model group than in the TCST group (P<0.05). Twenty four hours after cerebral ischemia/reperfusion, SOD activities were lower, whereas MDA contents and NO levels were higher in the TCST and model groups, compared with the sham operation group (P<0.05 or P<0.01). Compared with the model group, SOD activities were higher, whereas MDA contents and NO levels were lower in the TCST group (P<0.05).CONCLUSION: After TCST, cerebral infarct volume is reduced, SOD activities are increased, and MDA contents and NO levels are decreased compared to the model group in rats with focal cerebral ischemia/reperfusion injury. These changes may be associated with TCST.     

大鼠急性局灶性脑缺血再灌注脑组织NO含量和NOS活性的变化

目的探讨一氧化氮（ＮＯ）和神经元型ＮＯ合酶（ｎＮＯＳ）是否参与急性局灶性脑缺血再灌注的发病机理。方法采用栓红法建立大鼠大脑中动脉阻塞（ＭＣＡＯ）模型,观察脑组织ＮＯ含量和一氧化氮合酶（ＮＯＳ）活性的变化及ｎＮＯＳ抑制剂７－硝基吲唑（７－ＮＩ）对再灌注期两者的影响。结果缺血３０分种ＮＯ含量和ＮＯＳ活性显著升高,缺血３小进两者下降;再灌注３０分种ＮＯＴ和ＮＯＳ再次升高,而再灌注３小时两者又下降。７－Ｎ     

地高辛抗血清拮抗大鼠缺血再灌注引起的脑损伤

研究地高辛抗血清对缺血再灌注脑损伤的拮抗作用 ,采用了大鼠全脑缺血再灌注模型 ,比色法检测脑匀浆液中超氧化物歧化酶 (SOD)活性、丙二醛 (MDA)含量、脑细胞膜Na K 交换ATP酶活性、血清肌酸激酶(CK)含量 ;用放射免疫法检测脑匀浆液中内洋地黄素含量。结果发现 ,全脑缺血再灌注导致脑组织SOD活性和ATP酶活性显著下降 ,脑组织MDA水平、内洋地黄素水平和血清CK水平显著升高。地高辛抗血清能改善由于脑缺血再灌注所造成的SOD、ATP酶活性的下降以及MDA、CK和内洋地黄素水平的升高。结果表明 ,地高辛抗血清对脑缺血再灌注脑损伤具有保护作用 ,其作用机制与减轻脂质过氧化、促进自由基的清除以及改善脑能量代谢有关。这些作用可能是通过拮抗内洋地黄素的作用而实现的。     

大鼠脑缺血再灌流脑区一氧化氮变化的研究

目的研究大鼠脑缺血及再灌流后脑部一氧化氮的变化。方法采用荧光法和放射免疫法测定４个脑区一氧化氮（ＮＯ）代谢产物ＮＯ２和环磷酸鸟苷（ｃＧＭＰ）。结果脑缺血１０ｍｉｎ,各脑区ＮＯ２和ｃＧＭＰ含量明显增高;脑缺血３０ｍｉｎ,各脑区ＮＯ２和ｃＧＭＰ含量开始下降。缺血１０ｍｉｎ再灌流１５ｍｉｎ以及缺血３０ｍｉｎ再灌流１５ｍｉｎ,各脑区ＮＯ２和ｃＧＭＰ含量再次增加,与单纯脑缺血组相比,有显著差异性（Ｐ＜０．０５或Ｐ＜０．０１）。结论ＮＯ参与了脑缺血再灌流的损伤过程     

Effects of low molecular weight heparin-superoxide dismutase conjugate on serum levels of nitric oxide, glutathione peroxidase, and myeloperoxidase in a gerbil model of cerebral ischemia/reperfusion injury

BACKGROUND： Several studies have demonstrated that low molecular weight heparin-superoxide dismutase （LMWH-SOD） conjugate may exhibit good neuroprotective effects on cerebral ischemia/reperfusion injury though anticoagulation, decreasing blood viscosity, having anti-inflammatory activity, and scavenging oxygen free radicals. OBJECTIVE： To investigate the intervention effects of LMWH-SOD conjugate on serum levels of nitric oxide （NO）, glutathione peroxidase （GSH-Px）, and myeloperoxidase （MPO） following cerebral ischemia/reperfusion injury. DESIGN, TIME AND SETTING： A randomized, controlled, and neurobiochemical experiment was performed at the Institute of Biochemical Pharmacy, School of Pharmaceutical Sciences, Shandong University between April and July 2004. MATERIALS： A total of 60 Mongolian gerbils of either gender were included in this study. Total cerebral ischemia/reperfusion injury was induced in 50 gerbils by occluding bilateral common carotid arteries. The remaining 10 gerbils received a sham-operation （sham-operated group）. Kits of SOD, NO, and MPO were sourced from Nanjing Jiancheng Bioengineering Institute, China. LMWH, SOD, and LMWH-SOD conjugates were provided by Institute of Biochemistry and Biotechnique, Shandong University, China. METHODS： Fifty successful gerbil models of total cerebral ischemia/reperfusion injury were evenly randomized to five groups： physiological saline, LMWH-SOD, SOD, LMWH ＋ SOD, and LMWH. At 2 minutes prior to ischemia, 0.5 mL/65 g physiological saline, 20 000 U/kg LMWH-SOD conjugate, 20 000 U/kg SOD, a mixture of SOD （20 000 U/kg） and LMWH （LMWH dose calculated according to weight ratio, LMWH： SOD = 23.6：51）, and LMWH （dose as in the LMWH ＋ SOD group） were administered through the femoral artery in each above-mentioned group, respectively. MAIN OUTCOME MEASURES： Serum levels of NO, MPO, and GSH-Px. RESULTS： Compared with 10 sham-operated gerbils, the cerebral ischemia/reperfusion injury gerbils exhibited decreased s     

Electron paramagnetic resonance study on nitric oxide production during brain focal ischemia and reperfusion in the rat

The production of nitric oxide (NO) during brain focal ischemia and reperfusion was using diethyldithiocarbamate (DETC)/ Fe-citrate, NO trapping reagents, and electron paramagnetic resonance spectroscopy. The NO production is potentiated after 5 min of ischemia, and is continued during 60 min of ischemia. During the reperfusion period after 60 min of ischemia, NO was also produced. However, its production during reperfusion was not observed when the ischemia time was less than 15 min. The NO signal during reperfusion after 60 min of ischemia decreased after 15 min of reperfusion. These results suggest that NO production during ischemia is a physiological reaction for increasing cerebral blood flow, while NO production during reperfusion may be related to cellular damage.     

Constitutive nitric oxide synthases are responsible for the nitric oxide production in the ischemic aged cerebral cortex

Aged brain shows reduced biological plasticity to meet emergency conditions such as ischemia, a process in which nitric oxide (NO) and apoptosis have been shown to play important roles. Using a model of transient global ischemia, we have analyzed the NO system and the p53, bax and bcl-2 response in the cerebral cortex of aged rats. Although immediately after ischemia the NO level is maintained, the reperfusion period increases NO concentrations together with the following: (i) greater bulk-protein nitration mainly due to a 50-kDa immunoreactive band; (ii) an increase in p53 protein; and (iii) an up-regulation of Bax together with a down-regulation of Bcl-2. These results match up with induced endothelial nitric oxide synthase expression immediately after ischemia and in neuronal nitric oxide synthase with the reperfusion. However, inducible nitric oxide synthase was not altered with ischemia/reperfusion. Altogether, these data suggest that NO production in cerebral cortex of aged ischemic animals is due to the constitutive NO synthase isoforms. This response is accompanied by the increased expression of pro-apoptotic proteins.     

一氧化氮与TIA发作的关系研究

探讨一氧化氮（ＮＯ）与ＴＩＡ发作的关系。测定２３例ＴＩＡ患者ＴＩＡ发作期和ＴＩＡ发作后第３ｄ血清中ＮＯ、超氧化物歧化酶（ＳＯＤ）和丙二醛（ＭＤＡ）含量。研究发现，ＴＩＡ发作时ＮＯ、ＳＯＤ含量显著降低（Ｐ＜０．０５），ＭＤＡ含量显著增高（Ｐ＜０．００１）；ＴＩＡ发作后第３ｄ，ＮＯ含量回升至正常水平（Ｐ＞０．０５），ＳＯＤ含量增加但仍低于正常（Ｐ＜０．００５），而ＭＤＡ含量持续高于正常（Ｐ＜０．００１）。结果表明，ＮＯ含量降低与ＴＩＡ发作有关，ＴＩＡ发作后缺血再灌注期ＮＯ可能参与组织损伤。本文提示，ＮＯ对ＴＩＡ有防治作用，ＳＯＤ能增强ＮＯ的治疗作用，ＴＩＡ发作后宜积极抗氧化治疗。     

牛磺酸降低局灶性脑缺血引起的能量代谢紊乱和氧化损伤

目的观察牛磺酸对大鼠局灶性脑缺血引起的能量代谢紊乱和氧化损伤的影响。方法建立大鼠动脉腔内插线局灶性脑缺血模型,在缺血1h后给予牛磺酸(50mg/kg,iv),测定缺血2h再灌注22h时脑组织内ATP、乳酸和丙二醛(MDA)的含量、髓过氧化物酶(MPO)和超氧化物歧化酶(SOD)的活性及总抗氧化能力。结果牛磺酸明显降低再灌注22h时缺血脑组织内乳酸和MDA的含量及MPO活性,升高ATP的含量、SOD的活性和总抗氧化能力。结论牛磺酸可改善局灶性脑缺血损伤后的能量代谢,降低中性粒细胞的浸润,提高缺血组织的抗氧化能力,减轻局灶性脑缺血引起的过氧化损伤。