大剂量甲基强的松龙对大鼠局灶性缺血再灌注脑损伤的影响

目的 探讨大剂量甲基强的松龙（ＭＰ）对局灶性缺血再灌注大鼠脑保护作用的机理。方法采用大鼠局灶性脑缺血再灌注模型,观察缺血前后应用大剂量ＭＰ对大鼠大脑中动脉闭塞侧梗死体积的影响以及脑含水量的变化,同时观察脑组织病理学改变。结果 缺血前后ＭＰ治疗组大脑中动脉供血区脑梗死体积较盐水对照组明显减小（均Ｐ〈０．０１）;缺血性前后ＭＰ治疗组与盐水对照组脑含水量比较无明显差别（均Ｐ〉０．０５）。病理学发现盐水对照组织血管周围可见巨噬细胞浸润,而ＭＰ治疗组无此病理改变。结论 大剂量ＭＰ可改善缺血性脑损伤,其机理与减小缺血区梗死体积、抑制脑组织巨噬细胞浸润有关。     

内源性一氧化碳对局灶性脑缺血大鼠神经功能、梗死灶体积、脑含水量的影响

目的研究内源性CO浓度变化对局灶性脑缺血大鼠神经功能及脑组织含水量、梗死灶体积的影响.方法将48只S.D.大鼠随机分为2组(n=24), 一组为梗死灶体积组, 一组为脑含水量组.每一组又分为3小组, 分别为HO诱导剂、 HO抑制剂、生理盐水组(n=8).使用HO诱导剂、 HO抑制剂腹腔注射, 等量生理盐水腹腔注射作为对照组, 1 h后制成MCAO模型.栓塞后24 h观察局灶性脑缺血大鼠神经功能改变, 同时检测CO浓度、梗死灶体积、脑含水量.结果与生理盐水组相比, HO诱导剂组CO浓度明显升高(P＜0.01), 大鼠神经功能明显改善, 梗死灶体积、脑含水量明显降低, 各为(P＜0.01、 P＜0.01、 P＜0.05), 而HO抑制剂组CO浓度明显降低(P＜0.01), 大鼠神经功能缺失加剧, 梗死灶体积、脑含水量明显升高, 各为(P＜0.01、 P＜0.05、 P＜0.05).结论内源性CO是一种信使分子, 浓度升高对局灶性缺血的脑组织具有保护作用.     

甘露醇治疗大鼠缺血性脑水肿的形态学研究

目的研究甘露醇治疗脑水肿的机理及用药剂量。方法采用线栓法阻断大鼠大脑中动脉造成缺血性脑水肿，分别于缺血后１２ｈ、１６ｈ、２０ｈ、２４ｈ给予甘露醇１次、３次、５次和７次。用病理变化及梗塞病灶面积来观察水肿的程度。结果用甘露醇１次、３次、５次病灶减少，组织病理上为轻度缺血水肿脑。用７次后病灶增大，组织病理上为重度缺血水肿脑。结论病理变化及梗塞病灶面积可用来观察水肿的程度，甘露醇多次应用不能减少病灶侧脑组织含水量     

针刺对缺血性脑损伤大鼠的治疗作用及对GDNF表达水平和MAPKs信号转导通路的调节

目的研究针刺对局灶性缺血脑损伤大鼠GDNF表达水平和对pERK1／2及pElk-1水平的调节作用。方法采用线栓法建立大鼠大脑中动脉阻断（MCAO）模型，分为针刺组和缺血组，并对前者进行针刺治疗。24h后进行神经功能评分判断疗效，48h后进行TTC染色判断梗塞体积，并采用免疫组织化学和Western-blot法定位定量检测脑组织中GDNF表达水平及信号转导通路蛋白ERK1／2和ELK1磷酸化水平的变化。结果针刺可促进缺血性损伤大鼠神经功能的恢复，并减小脑梗塞体积（P〈0．05）。缺血灶周围区脑组织GDNF、pERK1／2及pElk1的含量均增高。针刺组pERK1／2及pElk1的含量低于缺血组（P〈0．01）；而GDNF的含量高于缺血组（P〈0．01）。结论针刺对缺血性脑损伤大鼠有保护作用，其作用机制可能涉及良性调节MAPK信号通路的反应性，上调GDNF的表达。     

米诺环素对大鼠脑缺血再灌注损伤的脑保护作用

目的探讨米诺环素对局灶性脑缺血再灌注损伤后的脑保护作用。方法 48只SD大鼠随机分为假手术组、生理盐水组、米诺环素治疗组和米诺环素预处理组。采用线栓法制作大脑中动脉缺血再灌注模型。用免疫组织化学法、放射免疫法、Hoechst染色和核磁共振T2WI扫描等方法,观察米诺环素对缺血再灌注大鼠脑组织COX-2、PGE2的表达、细胞凋亡及脑缺血体积的影响。结果米诺环素能降低缺血再灌注大鼠神经细胞凋亡率,减少COX-2、PGE2的表达,缩小脑梗死体积。结论米诺环素对大鼠局灶脑缺血再灌注损伤有脑保护作用。     

脑心通对大鼠局灶性脑缺血脑组织补体C3的影响

目的:探讨脑心通对大鼠局灶性脑缺血损伤后脑组织补体C3表达的影响。方法:参照longa等方法制成大鼠局灶性大脑中动脉阻断(MCAO)模型,将大鼠分为假手术组、生理盐水组、大剂量脑心通组、中剂量脑心通组、小剂量脑心通组,分别给予不同剂量药物,于术后6h,24h,48h,72h和7d进行神经功能评分(NDS),处死后取脑组织观察脑含水量的变化,病理切片HE染色观察组织病理学改变,免疫组织化学的方法测定补体C3的动态变化。结果:脑心通治疗组的神经功能评分均降低,病理损伤均减轻,大、中剂量脑心通组治疗后脑水肿明显减轻(P<0.05),补体C3的表达明显减少(P<0.05)。结论:脑心通可能通过减轻脑水肿,降低脑内补体C3的表达对大鼠缺血脑组织损伤产生保护作用。     

NE1反义抑制剂对局灶性脑缺血作用的初步研究

目的 探讨NR1反义寡核苷酸对局灶性脑缺血的治疗作用。方法 于大鼠大脑中动脉闭塞后2小时、24小时分别经侧脑室注射磷酸缓冲液（PBS）、错义寡核苷酸（MSODN）及反义寡核苷酸（ASODN），然后在不同时间点进行神经功能缺损评分，术后第5天进行Nissl染色、TTC染色及梗死体积比测定。结果 各组局灶性脑缺血的神经功能缺损评分无显著性差异；反义寡核苷酸治疗组的梗死体积比显著低于单纯缺血组；反义寡核苷酸治疗海马各区神经元损伤轻，神经元丢失相对较少。结论 局灶性脑缺血后侧脑室注入NR1反义寡核苷酸，可以减轻缺血脑组织病理学损害，具有脑保护作用。     

NR_1反义抑制剂对局灶性脑缺血作用的初步研究

目的　探讨NR1反义寡核苷酸对局灶性脑缺血的治疗作用。方法　于大鼠大脑中动脉闭塞后2小时、2 4小时分别经侧脑室注射磷酸缓冲液 (PBS)、错义寡核苷酸 (MSODN)及反义寡核苷酸 (ASODN) ,然后在不同时间点进行神经功能缺损评分 ,术后第 5天进行Nissl染色、TTC染色及梗死体积比测定。结果　各组局灶性脑缺血的神经功能缺损评分无显著性差异 ;反义寡核苷酸治疗组的梗死体积比显著低于单纯缺血组 ;反义寡核苷酸治疗组海马各区神经元损伤轻 ,神经元丢失相对较少。结论　局灶性脑缺血后侧脑室注入NR1反义寡核苷酸 ,可以减轻缺血脑组织病理学损害 ,具有脑保护作用。     

β-七叶皂苷钠对大鼠局灶性脑缺血再灌注后AQP4蛋白表达的影响

目的探讨大鼠局灶性脑缺血再灌注脑组织缺血区AQP4蛋白的表达情况及β-七叶皂苷钠的治疗作用和可能机制。方法采用大鼠大脑中动脉闭塞法(MCAO)制作局灶性脑缺血再灌注模型。应用干-湿比重法、TTC染色、免疫组化SABC法分别测定脑含水量、脑梗死体积及水孔蛋白4(aquaporin4,AQP4)的表达。结果假手术组AQP4蛋白有轻微的表达,而模型组、治疗组缺血损伤后表达升高,脑含水量增高,梗死脑组织出现,给予β-七叶皂苷钠的治疗组AQP4蛋白的表达下降,脑含水量明显降低,脑梗死体积减少,且β-七叶皂苷钠中高剂量组明显优于低剂量组(P<0.05)。结论脑缺血再灌注脑组织缺血区AQP4蛋白表达的上调与脑水肿的发生发展与有密切的关系,而β-七叶皂苷钠有抑制脑水肿发生的作用。     

促红细胞生成素对大鼠局灶性脑缺血再灌注后梗死体积和脑组织水肿的影响

目的 探讨促红细胞生成素(EPO)对大鼠脑缺血再灌注损伤的保护作用。方法 采用阻断大鼠一侧大脑中动脉(MCA)血流2小时,再灌注48小时制成局灶性脑缺血模型。于再灌注开始前,治疗组经腹腔注入EPO(3000 U/Kg);缺血组和假手术组给予生理盐水腹腔注射,48小时后断头取脑。制作 HE切片;以2％氯化-2,3,5三苯基四氮唑(TFC)对脑片进行染色;经图像分析仪计算梗死体积占全脑体积的百分比;同时用干湿重法测定脑组织的含水量。结果 与对照组相比,治疗组海马 CA_1区神经细胞减少(25.7±1.16)％,缺血组减少(31.2±1.49)％;治疗组与缺血组比较有显著性差异(P<0.01)。治疗组脑梗死体积比缺血组明显缩小(P<0.01)。治疗组脑组织含水量比缺血组明显减少(P<0.01)。结论 EPO能够显著降低脑组织含水量,抑制脑水肿,缩小脑梗死体积及减少神经细胞坏死,对脑缺血再灌注损伤有良好的保护作用。     

莱菔硫烷对大鼠局灶性脑缺血再灌注损伤的保护作用及机制研究

目的 探讨莱菔硫烷对大鼠局灶性脑缺血再灌注损伤的保护作用及机制.方法 采用线栓法制备大鼠大脑中动脉阻断局灶性脑缺血模型,分别于MCAO后1h腹腔注射莱菔硫烷2.5mg/kg、5mg/kg、10mg/kg.于缺血2h再灌注24h时进行神经行为缺损评分,TTC染色评价脑梗死体积,测定脑组织中超氧化物歧化酶(SOD)活力和丙二醛(MDA)含量.免疫荧光组织化学染色法检测黄核蛋白NQ01和脂质过氧化酶Prx6的表达.结果 莱菔硫烷给药组与对照组相比均能改善大鼠脑缺血再灌注后神经行为缺损评分,减少脑梗死体积.其中5mg/kg组能显著改善大鼠脑缺血再灌注后神经行为缺损评分,减少脑梗死体积,增强SOD活性,降低MDA含量.免疫荧光组织化学染色法提示NQ01和Prx6的表达明显增强.结论 莱菔硫烷对大鼠局灶性脑缺血再灌注损伤有神经保护作用,其机制可能与上调内源性抗氧化蛋白NQ01和Prx6的表达有关.     

长春西汀注射液在小鼠永久性脑缺血小胶质细胞表型转化中的作用研究

目的 研究长春西汀注射液对小鼠永久性大脑中动脉远端缺血后神经功能恢复及小胶质细胞表型 转化的影响。 方法 36只雄性C57BL/6J小鼠随机分为永久性脑缺血组6只、生理盐水组12只、长春西汀组12只和 假手术组6只,前三组用高频电刀凝断小鼠右侧大脑中动脉远端,制作永久脑缺血模型,假手术组 仅暴露大脑中动脉远端,不凝断血管。模型成功后,生理盐水组尾静脉注射生理盐水,每次150 μL, 每天1次,持续14 d;长春西汀组尾静脉注射长春西汀注射液,每次150 μL（4.55 mg/kg）,每天1次, 持续14 d。模型成功后3 d、5 d、7 d、9 d、11 d和14 d进行改良加西亚评分和转棒测试评价小鼠感觉和 运动神经功能;模型成功后14 d用免疫荧光标记神经元,评价各组神经元损伤情况,免疫荧光染色 梗死周围小胶质细胞表型标志物Iba1、CD16/32和CD206的表达,评价M1型（Iba1及CD16/32阳性）和 M2型（Iba1及CD206阳性）小胶质细胞表型转化情况。 结果 长春西汀组小鼠模型成功后11 d和14 d的改良加西亚评分和14 d的转棒测试中的时间及速度 测试结果均优于永久性脑缺血组,差异均有统计学意义。长春西汀组14 d时神经元损伤较永久性脑 缺血组（P =0.008）和生理盐水组（P =0.037）减轻。永久缺血组（P <0.001）和生理盐水组（P =0.005） M1型小胶质细胞表达高于假手术组;长春西汀组M1型小胶质细胞表达低于永久缺血组（P <0.001） 和生理盐水组（P =0.038）。长春西汀组M2型小胶质细胞表达高于假手术组、永久性脑缺血组和生 理盐水组（均P <0.001）。 结论 长春西汀注射液可能通过促进小胶质细胞表型由促炎向抗炎转变,减少神经元损伤,从而 在小鼠永久性脑缺血后发挥神经保护和促进功能恢复的作用。     

TMB—8对脑缺血大鼠脑血流量的作用

目的 研究8－（N，N－二乙胺）－n－辛基－3，4，5－三甲氧基苯甲酸酯（TMB－8）对局灶性脑缺血大鼠脑血流量（CBF）的作用。方法 用激光多谱勒血流仪测量大脑中动脉阻断（MCAO）大鼠脑血流量。分别于阻断前30分钟和阻断后20分钟给予TMB－8进行干预。结果 MCAO后，CBF迅速下降，维持恒定。阻断前30分钟给予TMB－8 0．5、1和2mg/kg，可剂量依赖性抑制CBF下降，阻断后20分钟给予TMB－8 1mg/kg，也能明显增加CBF。结论 TMB－8能预防和治疗MCAO局灶性脑缺血大鼠CBF减少，改善缺血区血供。     

Effects of retrograde perfusion of the brain with combined drug therapy after focal ischemia in rat brain.

BACKGROUND AND PURPOSE: The ischemic edema associated with blood-brain barrier permeability changes and the excess production of free radicals are serious complications in prolonged cerebral ischemia. We examined the efficacy of transvenous perfusion of the brain, starting treatment 5 hours after occlusion of the middle cerebral artery for a period of 2 hours in rats with the combined agents mannitol (10 ml/2 hr) and dexamethasone (1 mg/2 hr) to counter edema and verapamil (0.05 mg/kg/2 hr) for vasodilation. METHODS: In experiment 1, blood-brain barrier permeability changes were examined in five groups with six rats each: group C rats underwent 7 hours of middle cerebral artery occlusion with no treatment; group V, treatment with verapamil alone; group VD, treatment with verapamil and dexamethasone; group VM, treatment with verapamil and mannitol; and group VDM, treatment with verapamil, dexamethasone, and mannitol. In experiment 2, we examined local cerebral blood flow, ischemic tissue damage volume, and water content of cerebral hemispheres in two groups of 16 rats each subjected to the same treatment as groups C and VDM rats in experiment 1. RESULTS: There was a significant reduction of blood-brain barrier permeability changes in the ischemic cortex of rats in group VDM compared with rats in the other groups. In the group undergoing transvenous perfusion of the brain with the three combined agents, there was a significant improvement of cerebral blood flow (39-58%, p < 0.05) in the ischemic cortex and reduction of ischemic cerebral damage volume (22%, p < 0.01) and water content of the ischemic hemisphere (p < 0.05) compared with the control group. CONCLUSIONS: The therapeutic approach using combined agents is effective treatment when initiated within 5 hours of focal cerebral ischemia in rats.     

PI3K/AKT信号通路介导脂联素对脑缺血再灌注大鼠的保护作用

目的 探讨磷脂酰肌醇3激酶/蛋白激酶B（phosphatidylinositol-3-kinase/protein kinase B,PI3K/PKB）信号通路介导脂联素对脑缺血再灌注大鼠的保护作用。 方法 随机将SD大鼠分为假手术组、模型组、脂联素治疗组和PI3K/PKB抑制剂LY294002组（抑制剂组）,每组15只。通过线栓法构建大脑中动脉缺血模型,缺血1.5?h后再灌注。脂联素治疗组在再灌注2?h后,给予大鼠尾静脉注射脂联素（180?μg/100?g）;抑制剂组在再灌注2?h后给予大鼠尾静脉注射脂联素（180?μg/100?g）+LY294004（0.03?mg/100?g）;假手术组和模型组尾静脉注射相应体积的0.9%生理盐水（0.09?mL/100?g）。各组缺血再灌注24?h后,检测各组大鼠脑梗死面积和脑含水量;采用Longa 5分法进行神经功能缺损评分;蛋白质印迹法（Western blotting）检测大鼠脑组织PI3K、PKB、磷酸化的蛋白激酶B（phosphorylated PKB,p-PKB）和脂联素蛋白表达水平;酶联免疫吸附（enzyme linked immunosorbent assay,ELISA）法检测大鼠血清丙二醛（malondialdehyde,MDA）和超氧化物歧化酶（superoxide dismutase,SOD）水平。 结果 与假手术组相比,模型组大鼠的脑梗死面积、脑含水量、神经功能缺损评分和MDA水平均升高（均P<0.001）,SOD、脂联素、PI3K和p-PKB的表达水平均降低（均P<0.001）。与模型组比较,脂联素治疗组大鼠脑梗死面积、脑含水量、神经功能缺损评分和MDA水平均降低（均P<0.001）,SOD、脂联素、PI3K和p-PKB表达水平均升高（均P<0.001）;与脂联素治疗组比较,抑制剂组大鼠脑梗死面积、脑含水量、神经功能缺损评分和MDA水平均升高（均P<0.001）,SOD、脂联素、PI3K和p-PKB表达水平均降低（均P<0.001）。 结论 脂联素对脑缺血再灌注有明显保护作用,该保护机制可能与激活PI3K/PKB信号通路抑制氧化应激相关。     

门冬氨酸钾对局灶性脑缺血再灌注大鼠的保护作用研究

目的 观察门冬氨酸钾对大鼠局灶性脑缺血再灌注后神经细胞凋亡的保护作用。 方法 采用雄性SD大鼠右侧大脑中动脉闭塞模型,缺血2 h,再灌注22 h。大鼠随机分为5组,每组10 只,在缺血后1 h经腹腔注射给予生理盐水（1 ml/kg）或不同剂量门冬氨酸钾（10 mg/kg、25 mg/kg、 62.5 mg/kg和125 mg/kg）,观察不同剂量门冬氨酸钾对大鼠脑缺血再灌注后神经功能缺损和梗死 体积的影响。另取32只大鼠随机分为溶剂对照组和门冬氨酸钾组,在缺血后1 h腹腔注射生理盐水 （1 ml/kg）或门冬氨酸钾（62.5 mg/kg）,同时设立假手术组16只,检测三组大鼠脑组织三磷酸腺苷 （adenosine triphosphate,ATP）和乳酸水平（每组10只）,以及凋亡性细胞情况（每组6只）。 结果 与溶剂对照组比较,62.5 mg/kg剂量的门冬氨酸钾能显著改善神经功能缺损（P <0.001）, 降低梗死体积（P =0.011）;与溶剂对照组比较,25 mg/kg剂量的门冬氨酸钾能减少梗死体积 （P =0.040）,但神经功能评分无差异;10 mg/kg和125 mg/kg剂量的门冬氨酸钾组神经功能评分和 梗死体积与溶剂对照组均无差异。与溶剂对照组比较,门冬氨酸钾（62.5 mg/kg）能减少ATP的下降 （P =0.036）和细胞凋亡（P <0.001）。 结论 门冬氨酸钾对大鼠局灶性脑缺血再灌注后的细胞凋亡有保护作用。     

Pentoxifylline does not reduce cerebral ischemic edema in hypertensive rats

Continuous infusion of pentoxifylline 0.30 mg per kg per min starting 30 min after occlusion of the middle cerebral artery did not reduce the development of cerebral edema, as measured by specific gravity 6 h after occlusion in spontaneously hypertensive rats. On the contrary, in the parietal region the specific gravity was significantly lower in treated rats, indicating an increased water content. Thus, this study failed to show any beneficial effect of pentoxifylline in brain edema during early permanent ischemia.     

头孢曲松钠对大鼠脑缺血损伤的保护作用及其机制

目的 探讨在大鼠局灶性脑缺血模型中应用头孢曲松钠对脑缺血损伤的保护作用及其相关机制.方法 制备Wistar大鼠局灶性脑缺血模型,并按随机数字表法分为单纯缺血组(MCAO组)、头孢曲松钠治疗组(MCAO+CTX组)和盐水对照组,其中MCAO+CTX组为缺血90min时给予头孢曲松钠200 mg/kg.缺血后24 h、48 h、7 d时对各组大鼠进行神经行为学评分和脑水肿程度测定,同时比较各组大鼠皮层和海马谷氨酸转运体功能的差异.结果 随着缺血时间延长,各组大鼠神经行为学评分逐渐提高;脑水肿在缺血后24 h、48 h时逐渐加重,至7 d时已逐渐消退.与MCAO组比较,各时间点MCAO+CTX组大鼠神经行为学评分明显提高,脑水肿程度明显减轻,伤侧皮层及海马谷氨酸转运体功能明显增强,差异均有统计学意义(P＜0.05).结论 头孢曲松钠对大鼠局灶性脑缺血损伤具有保护作用,其机制可能与增强谷氨酸转运体功能从而减轻谷氨酸神经毒性作用有关.

Abstract：

Objective To explore the neuroprotective effect of ceftriaxone on cerebral ischemia injury in rats with focal cerebral ischemia and its possible mechanism. Methods Focal cerebral ischemic models were established in Wistar rats and randomly divided into ischemic group (performed middle cerebral artery occlusion [MCAO]), ceftriaxone (CTX) therapy group (given CTX at a dosage of 200 mg/kg 90 min after MCAO) and control group (given physiological saline only). Twenty-four and 48 h, and 7 d after MCAO, neurological behaviors and cerebral edema level were evaluated in these 3 groups;glutamate transporter function in the cortex and hippocampus of rats was compared between each 2 groups. Results With time extended, neurological behaviors scores were obviously elevated in every group;and cerebral edema became worse at 24 and 48 h and decreased 7 d after MCAO. As compared with that in the ischemic group, glutamate transporter function, level of edema and neurological behaviors scores in cortex and hippocampus of rats in the CTX therapy group were statistically increased at different ischemic time points (P<0.05). Conclusion Ceftriaxone has a neuroprotective effect against focal cerebral ischemia in rats, which may relate to increased glutamate transporter function and reduced glutamate neurotoxicity.     

Protective Effect of Zonisamide, an Antiepileptic Drug, Against Transient Focal Cerebral Ischemia with Middle Cerebral Artery Occlusion-Reperfusion in Rats

Summary: Purpose: The antiepileptic effects of zonisamide (ZNS) have been well documented experimentally and clinically. The purpose of this study was to examine whether ZNS reduces cerebral damage after transient focal ischemia in rats.
Methods : Ischemia was induced by a transient occlusion of the left middle cerebral artery (MCA) with a 3-0 nylon monofilament for 90 min. Neurological evaluation was performed by measuring the event of neurological deficit of the contralateral forepaw and hindpaw at 10 min and 1 day after MCA occlusion (MCAo). Brain infarct size was determined by measuring triphenyltetrazonium chloridenegative stained area of the serial brain sections 1 day after MCAo.
Results : The pre- or postischemic treatment with ZNS [(10–100 mgkg P.o.), 30 min before and 4 h after or 15 min and 4 h after the occlusion] markedly reduced cerebral damage in the ipsilateral hemisphere and the neurological deficit induced by transient ischemia. The reducing effect on the damage was observed in the cortical and subcortical regions. Preischemic treatment with carbamazepine (CBZ 60 mgkg p.0. twice 30 min before and 4 h after MCAo) tended to reduce the cerebral damage and neurological deficit, but the lower dose (20 mg/kg p.o. twice) did not. Valproate (VPA 1,000 mgkg p.o. twice) also had no effect.
Conclusions : ZNS at the anticonvulsant dose, unlike CBZ and VPA, ameliorated the brain infarction and the event of neurological deficit after transient focal cerebral ischemia. These data suggest that ZNS has therapeutic potential in protecting against ischemic cerebral damage, such as stroke.     

Neuroprotective effect of 4-amino-1,8-napthalimide, a poly(ADP ribose) polymerase inhibitor in middle cerebral artery occlusion-induced focal cerebral ischemia in rat

In the present study, neuroprotective effect of 4-amino-1,8-napthalimide (4-ANI), a poly(ADP-ribose) polymerase (PARP) inhibitor was investigated in middle cerebral artery occlusion (MCAo)-induced focal ischemia. Sprague-Dawley rats were subjected to 2 h of middle cerebral artery occlusion followed by 22 h of reperfusion. After 22 h of reperfusion rats were evaluated for cerebral infarction, neurological deficits, brain NAD levels, and in situ terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling (TUNEL). Focal ischemia produced significant infarct volume (201 +/- 14 mm3), neurological scores (2 +/- 0.5) and 28 +/- 4.5% brain NAD depletion. Ischemia was associated with increased in TUNEL positive cells in brain sections indicating DNA fragmentation. 4-ANI treatment (1 and 3 mg/kg, i.p.) significantly decreased infarct volume to 35 +/- 7% and 70 +/- 6%, respectively. Neurological functions were also significantly improved at these doses. 4-ANI (3 mg/kg) completely reversed brain NAD depletion and significantly reduced the increase in the number of TUNEL positive cells. Nevertheless, 4-ANI treatment did not alter cerebral blood flow and blood pressure. Our study suggests 4-ANI is a potent neuroprotective agent in focal cerebral ischemia and its neuroprotective effects may be attributed to reduction of NAD depletion and DNA fragmentation.