依托咪酯预处理对大鼠局灶性脑缺血-再灌注损伤的保护作用

目的 探讨依托咪酯预处理对脑缺血-再灌注损伤的保护作用。方法 18只雄性SD大鼠,随机均分为3组,即脑缺血-再灌注组、依托咪酯预处理组、脂微球对照组。采用颈内动脉线栓栓塞致大脑中动脉阻塞模型,监测肛温及血糖,并于再灌注24h后断头处死动物,取大脑切片行2,3,5-氯化三苯基四氮唑染色,测量并计算脑梗死容积百分比。结果 依托咪酯预处理组脑梗死百分比明显低于脂微球对照组（P＜0.01）,低于缺血-再灌注组（P＜0.05）。但缺血-再灌注组与脂微球对照组相比差异无统计学意义。结论 依托咪酯预处理后可明显减小大鼠局灶性脑缺血-再灌注损伤后的脑梗死面积。     

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。     

脑梗死大鼠神经功能缺损评分与脑梗死体积的相关性研究

目的:研究经典线栓法制备局灶性脑梗死模型大鼠的神经功能评分与脑梗死面积的相关性。方法:采用Zea Longa法制作大鼠局灶性脑梗死模型,在不同时间段对脑梗死大鼠进行神经功能缺损评分,并用2%TTC(氯化三苯基四氮唑)溶液对脑组织染色,计算脑梗死面积及梗死体积百分比。结果:线栓法制备局灶性脑梗死模型的大鼠24～48 h内神经功能评分降低,但脑梗死体积却增大,神经功能缺损评分与脑梗死体积百分比之间无相关性(r=-0.3762;P=0.88999)。结论:经典线栓法制备的局灶性脑梗死模型(大脑中动脉栓塞)中,尚不能认为大鼠的肢体运动功能与脑梗死体积有相关性。     

Ginsenoside Rd in Experimental Stroke: Superior Neuroprotective Efficacy with a Wide Therapeutic Window

Ginsenoside Rd (Rd), one of the main active ingredients in Panax ginseng, has been demonstrated to protect against ischemic cerebral damage in vitro and in vivo. In this study, we aimed to further define the preclinical characteristics of Rd. We show that Rd passes the intact blood-brain barrier and exerts protection in both transient and permanent middle cerebral artery occlusion (MCAO) in rats. In the dose-response study, Rd (10–50 mg/Kg) significantly reduced the infarct volume on postoperative days (PODs) 1, 3, and 7. This protection was associated with an improved neurological outcome for as many as 6 weeks after transient MCAO, as assessed by modified neurological severity score, modified sticky-tape test, and corner test. For comparison, Rd was significantly more effective than edaravone and slightly more effective than N-tert-butyl-alpha-phenylnitrone (PBN). In the therapeutic window study, Rd exhibited remarkable neuroprotection, even when administered for as many as 4 h after the recirculation of transient MCAO or after the onset of permanent MCAO. Furthermore, in female rats or 16-month-old male rats, the salutary effects of Rd were also observed. These findings suggest Rd is a promising neuroprotectant and provide support for future clinical studies to confirm whether Rd is beneficial in ischemic stroke.

Electronic supplementary material

The online version of this article (doi:10.1007/s13311-011-0051-3) contains supplementary material, which is available to authorized users.     

胰岛素对局灶性脑缺血再灌注损伤的作用

目的　观察胰岛素对脑缺血再灌注损伤的治疗作用。方法　制备易卒中型肾血管性高血压大鼠（ Ｒ Ｈ Ｒ Ｓ Ｐ） ,用线栓法复制大脑中动脉阻塞（ Ｍ Ｃ Ａ Ｏ） ,造成缺血６ ｈ 再灌注１８ ｈ ,术后立即及６ 小时后即时使用胰岛素,测定神经功能障碍评分及脑梗死体积的变化。结果　胰岛素可使神经功能障碍评分显著减低,梗死灶体积及其占全大脑体积比值,两半球体积差值显著减小。结论　胰岛素能减轻脑缺血再灌注损伤,早期用药效果更好。     

脑不对称性对大鼠局灶性脑缺血模型的梗死体积及行为功能的影响

目的 探讨不同时间点应用线栓法制作不同侧别大脑中动脉闭塞（middle c erebral a rtery o cclusion, MCAO）模型对大鼠神经功能和脑梗死体积的影响。 方法 参照Zea-Longa法制作大鼠局灶脑缺血模型,1.5 h后进行缺血再灌注（I/R）。36只SD大鼠随机 分为经左、右侧插线组,并对两组大鼠I/R后不同时间点（1、3、7 d）的神经功能缺损评分、平衡木试 验、水迷宫试验及脑梗死体积进行测定和比较。 结果 经左侧MCAO组大鼠的肢体运动平衡能力在I/R后1、3、7 d均显著低于右侧组,而记忆功能显 著高于右侧组,以I/R后7 d差异更明显。两组脑梗死体积在I/R后3 d时最大,7 d时最小;在I/R后1 d及 3 d时两组脑梗死体积无明显差异;而I/R后7 d时,左侧组梗死体积高于右侧组。 结论 栓塞左右侧对大鼠MCAO模型早期梗死体积影响不大,而后期左侧栓塞的梗死体积大于右侧。 并且左侧半球梗死引起的运动功能损害更重,右侧半球梗死引起的记忆功能缺损更严重。提示大鼠 左右脑半球可能存在结构和功能的不对称,从而影响局灶性脑缺血的结局。     

Neuroprotective effects of 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox), an antioxidant in middle cerebral artery occlusion induced focal cerebral ischemia in rats

OBJECTIVES: In the present study, we have investigated the neuroprotective potential of 6hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox), in middle cerebral artery occlusion (MCAO) induced focal cerebral ischemia. METHODS: Sprague-Dawley rats were subjected to 2 hours of MCAO followed by 22 or 70 hours of reperfusion. After reperfusion, rats were evaluated for neurological deficits and cerebral infarction. Brain malondialdehyde (MDA) level and in situ terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling (TUNEL) were also estimated. RESULTS: Focal cerebral ischemia produced a significant infarct volume and neurological scores as compared with sham-operated animals. Cerebral ischemia reperfusion injury was associated with an increase in lipid peroxidation in ipsilateral and contralateral hemisphere of brain along with an increase in TUNEL positive cells in ipsilateral hemisphere of brain sections indicating oxidative stress and DNA fragmentation, respectively. Trolox (10 and 30 mg/kg, i.p.) treatment significantly decreased neurological damage which was evident from the reduction in infarct volume and neurological score. Trolox (30 mg/kg) also attenuated oxidative stress and DNA fragmentation. DISCUSSION: Oxidative stress-induced neuronal damage is implicated in the pathophysiology of cerebral ischemia. Our study suggests that Trolox is a potent neuroprotective agent in focal cerebral ischemia and its neuroprotective effects may be attributed to the reduction of lipid peroxidation and DNA fragmentation.     

金钗石斛多糖上调锌指蛋白A20表达减轻大鼠缺血性脑损伤

目的观察金钗石斛多糖调控锌指蛋白A20表达抑制NF-κB信号通路减轻大鼠缺血-再灌注脑损伤的作用机制。方法 SD大鼠随机分为假手术组、脑缺血-再灌注模型组、金钗石斛多糖治疗组(200 mg/kg)、金钗石斛多糖治疗+A20沉默组和金钗石斛多糖治疗+空病毒载体组。建立局灶性脑缺血-再灌注模型,观察金钗石斛多糖对锌指蛋白A20 mRNA和蛋白表达的影响。比较各组大鼠神经功能评分和脑梗死体积,检测磷酸化IKKβ蛋白和胞核p65蛋白的表达量。结果分别从再灌注6 h和12 h开始,金钗石斛多糖治疗组大鼠脑组织A20 mRNA和蛋白水平均较脑缺血-再灌注模型组明显增高(均P0.01)。同脑缺血-再灌注模型组相比,金钗石斛多糖治疗组大鼠神经功能评分明显改善(P0.001),脑梗死体积明显减小(P0.01),脑组织磷酸化IKKβ和胞浆p65表达水平均明显下降(分别为P0.001,P0.01);而A20沉默则逆转了金钗石斛多糖上述治疗效果,各项指标均明显恶化(均P0.01)。结论金钗石斛多糖通过上调锌指蛋白A20表达抑制NF-κB信号通路减轻大鼠缺血性脑损伤。     

The selective oestrogen receptor modulator, LY362321, is not neuroprotective in a rat model of transient focal ischaemia

Selective oestrogen receptor modulators (SERMs) may offer improved alternatives to oestrogen as neuroprotectants in experimental stroke. The present study investigated the role of a novel SERM, LY362321, in a rat model of transient middle cerebral artery occlusion (MCAO). Female Sprague-Dawley rats were ovariectomised and began receiving daily s.c. injections of either 1 mg/kg (n = 13), 10 mg/kg (n = 14) of LY362321, or vehicle (n = 13). The left MCA was temporarily occluded (90 min), with cortical blood flow monitoring, at 12 days post ovariectomy. Sensorimotor function was assessed using a neurological score prior to the MCAO and daily for 3 days following the MCAO. Tissue was processed for infarct volume assessment using 2,3,5-triphenyltetra-zolium chloride staining. The results indicated that there were no significant differences amongst groups in cortical blood flow during the MCAO. Furthermore, there was no significant difference in infarct size amongst vehicle, 1, and 10 mg/kg treated animals: 22.9 ± 5.0, 16.7 ± 4.2, and 21.1 ± 4.1, respectively, one-way anova [F(2,32) = 0.542, P = 0.587]. The MCAO induced a significant decline in neurological score in the vehicle group (from 14 to 7 at 24 h post-MCAO) but this was not significantly affected by LY362321 at either dose. In conclusion, pretreatment with a low or high dose of the novel SERM LY362321 did not significantly influence cerebral blood flow, infarct volume, or sensorimotor function in rats exposed to transient MCAO.     

Dietary phytoestrogens improve stroke outcome after transient focal cerebral ischemia in rats

As phytoestrogens are postulated as being neuroprotectants, we assessed the hypothesis that dietary isoflavone-type phytoestrogens are neuroprotective against ischemic stroke. Transient focal cerebral ischemia (90 min) was induced by middle cerebral artery occlusion (MCAO) following the intraluminal thread technique, both in rats fed with soy-based diet and in rats fed with isoflavone-free diet. Cerebro-cortical laser-Doppler flow (cortical perfusion, CP), arterial blood pressure, core temperature, PaO2, PaCO2, pH and glycemia were measured before, during and after MCAO. Neurological examination and infarct volume measurements were carried out 3 days after the ischemic insult. Dietary isoflavones (both glycosides and aglycones) were measured by high-performance liquid chromatography. Neither pre-ischemic, intra-ischemic nor post-ischemic CP values were significantly different between the soy-based diet and the isoflavone-free diet groups. Animals fed with the soy-based diet showed an infarct volume of 122 +/- 20.2 mm3 (19 +/- 3.3% of the whole ipsilateral hemisphere volume). In animals fed with the isoflavone-free diet the mean infarct volume was significantly higher, 191 +/- 26.7 mm3 (28 +/- 4.1%, P < 0.05). Neurological examination revealed significantly higher impairment in the isoflavone-free diet group compared with the soy-based diet group (3.3 +/- 0.5 vs. 1.9 +/- 0.5, P < 0.05). These results demonstrate that dietary isoflavones improve stroke outcome after transient focal cerebral ischemia in such a way that a higher dietary isoflavone content results in a lower infarct volume and a better neurological status.     

局灶性缺血预处理对脑梗死大鼠神经生长因子表达的影响

目的:研究局灶性缺血预处理对脑梗死大鼠神经生长因子(nerve growthfactor,NGF)表达的影响,探讨缺 血预处理诱导脑缺血耐受机制。方法:SD大鼠随机分为3组。预缺血组和假手术组在大脑中动脉缺血(MCAO)前3天 分别接受10min的预缺血或假手术,MCAO 2h后再灌注22h处死;对照组两次均为假手术,比较各组神经功能评分、梗 死体积及NGF的表达。结果:预缺血组神经功能评分、梗死体积较假手术组减少(P<0．05),NGF表达明显高于其余两 组(P<0．01)。结论:局灶性缺血预处理可诱导脑缺血耐受的产生,其作用机制可能与NGF的表达改变有关。     

大鼠急性脑梗死溶栓治疗时间窗的研究

目的　研究尿激酶溶栓治疗大鼠急性脑梗死的时间窗。方法　用自体血栓法制作大鼠大脑中动脉闭塞 (MCAO)模型 ,在栓塞后 30、6 0、90、12 0、180min(A、B、C、D、E组 )经静脉注射尿激酶 (5万U/kg)溶栓 ,用神经功能缺损评分、TTC染色测梗死体积、核磁共振 (MRI)及病理学观察 ,比较不同时间点溶栓的疗效及安全性。结果　MCAO后 90min内溶栓 (A、B、C组 )能显著改善神经功能 ,缩小梗死体积 (P <0 .0 5 ) ,12 0min以后溶栓组 (D、E组 )与对照组无显著性差异 (P >0 .0 5 ) ,且并发脑出血率高 (31.3% )。结论　本研究提示大鼠脑梗死溶栓治疗最佳时间窗为栓塞后 90min内 ,溶栓治疗时间越早 ,疗效及安全性越高。     

尿激酶联合镁剂治疗大鼠急性脑梗死的实验研究

目的　观察尿激酶溶栓联合硫酸镁神经保护对大鼠急性脑梗死的疗效。方法　应用光化学诱导法建立大鼠大脑中动脉闭塞(MCAO)模型,分别于术后2 h、6 h和10 h 3 个时间点进行干预,每个时间点内再分为生理盐水对照组、尿激酶溶栓组、尿激酶加硫酸镁治疗组,术后24 h观察大鼠神经功能缺损评分及脑梗死体积的变化。结果　MCAO后2 h尿激酶溶栓组神经功能显著改善,梗死体积缩小(与生理盐水对照组相比,P<0.01),尿激酶加硫酸镁治疗组效果更好;MCAO后6 h、10 h尿激酶溶栓组与生理盐水对照组相比无显著性差异(P>0.05),而尿激酶加硫酸镁治疗组的神经功能缺损评分、脑梗死体积与生理盐水对照组及尿激酶溶栓组相比有显著差异(P<0.05或P<0.01)。结论　早期脑梗死特别是2 h内的超早期脑梗死应用尿激酶溶栓有效;加用镁剂进行神经保护可对尿激酶溶栓疗效产生协同作用,并可能扩大脑梗死溶栓治疗的时间窗。     

Comparison of silicon-coated nylon suture to plain nylon suture in the rat middle cerebral artery occlusion model

A variety of intraluminal sutures have been used in the middle cerebral artery occlusion model (MCAO) of focal ischemia. In the present study we tested commercially available silicon-coated nylon suture in the MCAO model and compared the results to traditional monofilament nylon suture occlusion. Twelve Sprague-Dawley male rats were randomly divided two groups, MCAO with 4-0 nylon suture (Group N, n=6) and MCAO with silicone-coated 4-0 nylon suture (Group S, n=6). Rats were sacrificed 24 h after reperfusion. Assessment included mortality rates, neurological evaluation, and infarct volume. One rat died in each group from subarachanoid hemorrhage. Neurological evaluation demonstrated that Group S tended to have worse neurological outcomes than Group N, although this difference was not statistically significant. On TTC stain Group S had significantly larger infarct volumes than Group N. We conclude that the commercially available silicone-coated occlusion suture provides better occlusion of the middle cerebral artery than the traditional uncoated nylon suture. Classification: Disease-related neuroscience (Section 6).     

Effects of RSR13, a synthetic allosteric modifier of hemoglobin, alone and in combination with dizocilpine, on outcome from transient focal cerebral ischemia in the rat

This study examined the effect of a pharmacologically induced rightward shift in the partial pressure of oxygen at which 50% of hemoglobin is saturated (P50) on outcome from transient focal cerebral ischemia in the rat. Halothane anesthetized rats (n=20 per group) were given saline or a single 15-min infusion of 150 mg/kg RSR13 (2-[4-[[3,5-dimethylanilino) carbonyl]methyl]phenoxy]-2-methylproprionic acid) intravenously before or 30 min after onset of 75 min of middle cerebral artery filament occlusion (MCAO). Seven days later, severity of hemiparesis and cerebral infarct size were examined. RSR13 alone did not significantly improve outcome. Conscious normothermic rats (n=12 per group) were also given RSR13 (150 mg/kg) or 0.9% NaCl intravenously and subjected to 75 min of MCAO with 7 days of recovery. Again, RSR13 alone did not significantly reduce infarct size or improve neurologic score. A dose-response curve for dizocilpine (MK-801) was then constructed in conscious normothermic rats subjected to 75 min of MCAO. Dizocilpine (0.5 mg/kg i.v.) caused a 90% reduction in mean infarct size while 0.25 mg/kg reduced infarct size by 48%. Other rats were then subjected to 75 min of MCAO after being given dizocilpine (0.25 mg/kg i.v.; n=18) or RSR13 (150 mg/kg i.v. )+dizocilpine (0.25 mg/kg i.v.; n=15). RSR13+dizocilpine resulted in smaller cortical infarct volume (8+/-14 mm3 vs. 34+/-37 mm3, p<0.02) and total cerebral infarct volume (46+/-28 mm3 vs. 81+/-60 mm3, p<0. 05) compared to dizocilpine alone, respectively. We conclude that a pre-ischemic peak increase in P50 of approximately 25 mmHg alone is insufficient to reduce focal ischemic injury, but may be advantageous when used in conjunction with other neuroprotective agents.     

利用激光散斑成像技术观察尤瑞克林对脑梗死大鼠脑血流的影响

目的 利用激光散斑成像技术研究尤瑞克林对大鼠脑梗死后局部脑血流的影响.方法 成年雄性SD大鼠24只,线栓法制备大鼠永久性大脑中动脉梗死模型.激光散斑成像系统观测缺血半球皮质及大脑中动脉供血区血流,2,3,5-三苯基氯化四氮唑(TTC)染色法测定脑梗死体积,并进行神经功能评分.结果 皮质及大脑中动脉供血区血流在大剂量组第1天及第2天给药后均有明显改善,部分大脑皮质血管增粗,血流速度加快,小剂量组及生理盐水组无明显变化,脑缺血48 h后,大、小剂量尤瑞克林组及生理盐水组的梗死体积分别为10.14%±3.02%,25.99%±3.90%,27.10%±3.32%,大剂量组与生理盐水组比较差异有统计学意义(F=61.14,P<0.01),小剂量组与生理盐水组比较差异无统计学意义.缺血后4 h,大剂量组神经功能损伤明显改善,小剂量组及生理盐水组无明显改变,36 h各组间的神经功能评分差异无统计学意义.结论 尤瑞克林可以减少大鼠局灶性脑缺血后梗死体积,延缓神经功能损伤,其作用可能与促进侧支循环的开放,增加大脑皮质和缺血区血流有关.     

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。     

Delayed Decompressive Craniectomy Improves the Long-term Outcomes in Hypertensive Rats with Space-occupying Cerebral Infarction

Background and Purpose

No experimental data has been published on the long-term effects of decompressive craniotomy in hypertensive rats with space-occupying cerebral infarction. The aim of the present study was to investigate the efficacy of decompressive craniectomy in a middle cerebral artery occlusion (MCAO) model of hypertensive rats in a prolonged period.

Methods

Totally 92 stroke-prone renovascular hypertensive rats (RHRSP) were subjected to left MCAO by an endovascular occlusion technique. The decompressive craniectomy was performed on 26 RHRSP at 1 and 24 h after MCAO, respectively. Infarct volume, neurological performance, and mortality were evaluated at 1, 2, 4, and 8 weeks after MCAO.

Results

The mortality was reduced from 52.5% in controls to 7.7% and 23.1% in the rats underwent craniectomy at 1 and 24 h after MCAO, respectively (P < 0.05, respectively). All of the treated rats presented smaller infarct volume from 1 week to 8 weeks and better neurological performance at 4–8 weeks after MCAO compared to the controls (P < 0.05, respectively). The craniectomy at early stage was more effective than that at late stage in reducing infarct volume and improving neurological performances at 1 and 2 weeks (P < 0.05, respectively). However, there was no significant difference in infarct volume and neurological scores between the treated groups of rats at 4 and 8 weeks after MCAO (P > 0.05).

Conclusions

Although the early craniectomy is more effective than delayed craniectomy in improving short-term outcome, the latter has the similar beneficial effects as early craniectomy on long-term outcome in hypertensive rats with space-occupying cerebral infarction.     

bcl-xl over-expression in transgenic mice reduces cerebral ischemia/reperfusion injury*☆

BACKGROUND： Basal cell lymphoma-extra large （bcl-xl） can inhibit neuronal apoptosis by stabilizing the mitochondrial membrane and suppressing cytochrome C release into the cytoplasm. OBJECTIVE： This study aimed to further investigate the cascade reaction pathway of cellular apoptosis. We established an ischemia/repcrfusion model by middle cerebral artery occlusion （MCAO） in transgenic and wild-type mice, and observed changes in the number and distribution of apoptotic neural cells, differences in cerebral infarct volume, in neurological function score, and in cytochrome C expression in the ischemic cerebral cortex, at different time points, DESIGN AND SETTING： The present gene engineering and cell biology experiment was performed at the Laboratory of Biology, Hubei Academy of Agricultural Sciences and at the Laboratory of Immunology, Tongji Medical College, Huazhong University of Science and Technology. MATERIALS： Male bcl-xl over-expression Kunming mice aged 8 weeks and age-matched male wild-type mice were used for this study. Terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling （TUNEL） kits were purchased from Boliman, France. Cytochrome C antibody and Bcl-x immunohistochemical kit were purchased from PharMingen, USA and Santa Cruz Biotechnology, USA, respectively. METHODS： Following MCAO and reperfusion, apoptosis in the ischemic cerebral cortex was detected by the TUNEL assay. Prior to MCAO and 3 hours after reperfusion, the Bcl-xl protein level in the ischemic cerebral cortex was measured by immunohistochemistry. At 3, 6, 12 and 24 hours after reperfusion, the level of cytochrome C in the ischemic cerebral cortex was examined by western blot analysis. Subsequent to MCAO, cerebral infarct volume measurement and neurological examination were performed. MAIN OUTCOME MEASURES： Neural cell apoptosis and cytochrome C expression in the ischemic cerebral cortex; cerebral infarct volume and neurological function score. RESULTS： Twenty-four hours after reperfusion, cerebral inf     

Kallikrein基因转导对脑缺血再灌注后局部血流灌注恢复的作用

目的 探讨Kallikrein基因对脑缺血再灌注后梗死灶周围血管增生与局部脑血流灌注恢复的作用.方法 建立大鼠脑缺血再灌注模型,术后将90只大鼠按照随机数字表法分为3组.每组30只,分别是空白对照组、注射生理盐水、注射pAdCMV-人组织激肽释放酶(HTK)组.各组大鼠又分为治疗后12 h、24 h及72 h组,每组各10只.治疗前后行大鼠神经功能缺损评分.TTC染色方法测定脑梗死面积的变化,用免疫组化检测外源性HTK的表达以及局部血管内皮生长因子(VEGF)的表达,并通过14C-iodoantipyrine微示踪技术检测局部脑血流灌注(rCBF)情况.结果 与其他两组相比,pAdCMV-HTK组大鼠脑梗死面积在治疗后24h已有明显减小,72h后这种变化更明显,差异有统计学意义(P<0.05);在治疗后24 h,pAdCMV-HTK组大鼠神经功能缺损评分明显低于生理盐水组及空白对照组,治疗后72h差异更明显,差异有统计学意义(P<0.05).vEGF阳性细胞主要分布于脑梗死灶周边皮质与部分白质;pAdCMV-HTK组VEGF表达在治疗后12h、24h、72h均明显高于生理盐水组及空白对照组,差异有统计学意义(P<0.05).各组缺血再灌注后脑梗死灶周围白质与皮质rCBF均较对侧稍减少:pAdCMV-HTK组治疗后12h,梗死灶周围白质与皮质rCBF较空白对照组与生理盐水组有增高.但不明显,差异无统计学意义(P>0.05),而在治疗24h、72 h后rCBF则明显增高,差异有统计学意义(P<0.05).结论 在脑缺血再灌注后,Kallikrein基因转导可增加梗死灶周围脑组织的血管增生,改善rCBF,减小梗死面积,从而达到保护缺血神经细胞功能的作用.