Metabolic Changes in Rats with Photochemically Induced Cerebral Infarction and the Effects of Batroxobin:A Study by Magnetic Resonance Imaging,~1H-and ~(31)p-Magnetic Resonance Spectroscopy

Metabolic changes in rats with photochemically induced cerebral infarction and the effects ofbatroxobin were investigated 1,3,5 and 7 days after infarction by means of magnetic resonanceimaging (MRI),~1H-and ~(31)p-magnetic resonance spectroscopy(MRS).A region of T_2 hyperintensitywas observed in left temporal neocortex in infarction group and batroxohin group 1,3,5 and 7 daysafter infarction.The volume of the region gradually decreased from 1 day to 7 days after infarction.The ratio of NAA/Cho Cr in the region of T_2 hyperintensity in the infarction group was significantlylower than that in the corresponding region in the sham-operated group 3,5 and 7 days afterinfarction respectively(P<0.05).Lac appeared in the region of T_2 hyperintensity in the infarctiongroup 1,3,5 and 7 days after infarction,but it was not observed in the corresponding region insham-operated group at all time points.Compared with the sham-operated group,the ratios ofβATP/PME PDE and PCr/PME PDE of the whole brain in the infarction group were significantlylower 1,3 and 5 days after infarction respectively(P<0.05),and the ratio of βATP/PCr also wassignificantly lower 1 day after infarction(P<0.05).Batroxobin significantly decreased the volume ofthe region of T_2 hyperintensity 1 and 3 days after infarction(P<0.05),significantly increased the ratioof NAA/Cho Cr in the region 5 and 7 days after infarction(P<0.05),significantly decreased theratios of Lac/Cho Cr and Lac/NAA in the region 5 and 7 days after infarction(P<0.05),andsignificantly increased the ratios of βATP/PME PDE and βATP/PCr in the whole brain 1 day afterinfarction(P<0.05).The results indicated that the infracted region had severe edema,increased Lacand apparent neuronal dysfunction and death,and energy metabolism of the whole brain decreasedafter focal infarction,and that batroxobin effectively ameliorated the above-mentioned abnormalchanges.     

THE EFFECT OF RADIX SALVIAE MILTIORRHIZAE(RSM)ON SUBSTANCEP IN CEREBRAL ISCHEMIA—ANIMAL EXPERIMENT

The levels of substance P(SP)in rat brains were assayed in 64 rats.Bilateral common carotid ar-tery ligation was done in 49 rats.Half an hour before ligation,25 rats were given 10 g/kg ofRSM;24 rats were given the same volume of normal saline as controls.Sham operation was donein 15 rats.Half an hour and 3 hours after cerebral ischemia,the rats were quickly decapitated.SP concentration was assayed in the cerebral cortex,caudate nucleus and brain stem.Insaline-treated animals,the SP level of caudate nucleus at 3-hour group was significantly de-creased as compared with the 0.5-hour group and sham-operated group respectively.No signifi-cances were found among RSM-treated groups and sham-operated groups.The SP levels wereshown:brain stemcerebral cortex.The preliminary results suggest that SPmay be involved in the pathophysiologic procedures of cerebral ischemia and RSM mayattenuate the dysfunction of SP during cerebral ischemia.     

THE EFFECT OF RADIX SALVIAE MILTIORRHIZAE ON VASOACTIVE INTESTINAL PEPTIDE IN CEREBRAL ISCHEMIA:AN ANIMAL EXPERIMENT

The levels of vasoactive intestinal peptide(VIP)in three regions of rat brain were assayed in 62 rats.Bilateral common carotid artery ligation was donein 50 rats.Half an hour before ligation 26 rats weregiven 10 g/kg of Radix Salviae Miltiorrhizae(RSM);24 rats were given same volume of normalsaline as controls.A sham operation wasdone in 12 rats.Half an hour(n=30)and 3hours(n=32)after operation,the rats were quicklydecapitated.VIP levels were assayed in cerebralcortex,hippocampus and caudate nucleus,in salin-treated animals,VIP levels of cerebral cortex andcaudate nucleus at 3 hour group were significantlydecreased compared with the sham-operated group.No significant difference was found between RSM-treated and sham-operated groups.The preliminaryresults suggest that VIP may be involved in thepathophysiological procedures of cerebral ischemiaand RSM may attenuate the dysfunction of VIPduring cerebral ischemia.     

Effects of different frequencies of electro-acupuncture at Shuigou(GV 26) on recovery of motor function in rats with focal cerebra ischemic injury

OBJECTIVE:To investigate the effects of different frequencies of electro-acupuncture at Shuigou(GV 26) on the latent period and wave amplitude of motor evoked potentials(MEPs) in rats with focal cerebral infarction.METHODS:Fifty healthy male Wistar rats were randomly divided into five groups:controls,model,2 Hz Shuigou,50 Hz Shuigou and 100 Hz Shuigou.There were 10 rats in each group.Using a modification of a technique for middle cerebral artery occlusion,focal cerebral ischemic injury was induced in all rats except those in the control group.The rats in the control group received no treatment.After behavioral deficit had been evaluated using the Zausinger 6-point neurological function score,therats in the Shuigou groups underwent acupuncture and continuous wave stimulation at a frequency of 2 Hz,50 Hz or 100 Hz(intensity 1 mA) for 10 min twice daily for 3 days.The control and model groups underwent no intervention.Zausinger 6-point neurological function score and MEPs were measured 72 h after the start of treatment.RESULTS:The neurological function scores of the three Shuigou groups were significantly higher than those of the model group(P<0.05).There was no significant difference between sides in the latency and amplitude of MEPs in the model group(P> 0.05).The latency on the affected side in the model group was significantly longer than that in the control group(P<0.05) and the amplitude on affected side was significantly reduced(P<0.01).After 3 days of electro-acupuncture,the latency on the affected side in the 2 Hz Shuigou group was significantly shortened(P<0.05) and the amplitude was significantly increased(P<0.05) compared with the model group.CONCLUSION:Low frequency electro-acupuncture at Shuigou(GV 26) can promote recovery of motor function after focal cerebral ischemic injury in rats.     

The Effect of Acupuncture on Plasma Endothelin Content in Cerebral Infarction Patients——A Clinical Study

Objective: To observe the effect of acupuncture on content of plasma endothelin in cerebral infarction patients. Methods: The plasma endothelin content in cerebral infarction patients was observed before and after acupuncture, which was compared with that of the medication group and the healthy subjects. Results: Before treatment, the content of plasma endothelin in cerebral infarction patients was significantly higher than that of the healthy subjects (P<0.01); after acupuncture treatment, the content greatly decreased (P<0.01), and there was a statistically significant difference between the acupuncture group and the medication group (P<0.05). Conclusion: Acupuncture may decrease the content of plasma endothelin in the cerebral infarction patients, improve the vascular elasticity, and improve the cerebral circulation of blood.     

Electro-acupuncture combined with transcranial magnetic stimulation improves learning and memory function of rats with cerebral infarction by inhibiting neuron cell apoptosis

This study examined the effect of electro-acupuncture (EA) combined with transcranial magnetic stimulation (TMS) therapy at different time windows on learning and memory ability of rats with cerebral infarction and the underlying mechanism.Two hundred SD rats were randomly divided into four groups:normal group,sham-operated group,model group and EA+TMS group,and each group was then divided into five sub-groups in terms of the different time to start treatment post operation:6,12,24,48 and 72 h.Cerebral infarction models were established in the model and the EA+TMS groups by left middle cerebral artery occlusion/reperfusion (MCAO/R).After treatment for 14 d,the Morris water maze test was applied to examine the spatial learning and memory abilities of rats.In infarcted area,the expression of caspase-3 was immunohistochemically detected,and real-time fluorescent quantitative PCR was used to measure the expression of Bcl-2 mRNA.The results showed that in EA+TMS group compared with model group at the same treatment time windows,the escape latency was substantially shortened,the expression of caspase-3 was considerably decreased and the expression level of Bcl-2 mRNA significantly increased (P<0.05).In the EA+TMS sub-groups,the escape latency was shortest,the expression level of caspase-3 lowest,and the expression level of Bcl-2 mRNA highest at the treatment time window of 24 h.It was concluded that EA combined with TMS can promote neurological function of rats with cerebral infarction by increasing the expression level of Bcl-2 mRNA and decreasing the expression of caspase-3.The best time window is 24 h after perfusion treatment to ischemia.     

电针对局灶性脑缺血再灌注大鼠脑细胞凋亡及神经功能恢复的影响

Objective To investigate the influence of acpuncture on free calcium in rat brain cells after focal cerebral ischemia reperfusion.Methods 145 adult male SD rats were randomly divided into control group,simple ischemia reperfusion group and acupuncture with ischemia reperfusion group.The middle cerebral artery occlusion/reperfusion (MCAO/R) rat model was established by the modified Longa occlusion method. ①The part of free calcium in rat brain cells,focal cevebral ischemia model of rats were made by thread locking up the blood vessel for 15 min.30 min later after reperfusion, the Baihui and Shuigou Point in Du meridian were acupunctured electrically 30 min.After 3h, 6h and 12h, the rat was killed and its brain cells were made into single cell suspension,marked by Fluo-3/AM.The fluorescence optical density was recorded by laser confocal microscopy.②The part of nerve functional reconstruction, focal cevebral ischemia model of rats were made by thread locking up the blood vessel for 12 hours.30 min later after reperfusion, the Baihui and Shuigou Point in Du meridian were acupunctured electrically 30 min.After 7 d, 14 d,30 d,60 d and 90 d, the rat was forced to detect it's strength of the dog.Results ①Free calcium in rats of acupuncture therapy group(6h:10.96±1.18;2h:20.9±4.37) was significantly less than that in control group in 6 h and 12 h after reperfusion (6 h: 16.87 ± 3.56,12 h: 34.10 ±1.06)(P<0.05).②The dog in rats of acupuncture therapy group was significantly more than that in control group in 7 d, 14 d after reperfusion (P＜ 0.05 ).No difference of the dog was detected in 30 d ,60 d and 90 d after reperfusion between the two groups.Conclusion Acupunture could decreases the concentration of free calcium and the expression of Caspase-3 mRNA in rat brain cells after focal cerebral ischemia reperfusion, and it can facilitate the recovery of nerve function.     

Dynamic expression of glucose transporters 1 and 3 in the brain of diabetic rats with cerebral ischemia reperfusion

Background Blood glucose control improves the outcome of diabetic patients with stroke, but the target range of blood glucose control remains controversial. The functional recruitment of ischemia penumbra is extremely important to the recovery after stroke. The present study aimed to explore the expression of brain-type glucose transporters （GLUT1 and GLUT3） in cerebral ischemic penumbra at different blood glucose levels and different ischemic-reperfusion time in diabetic hypoxia-ischemia rats. The results might provide an experimental basis for clinical treatment of diabetic patients with stroke. Methods The Wistar rats included in this study were randomly assigned to 4 groups （50 rats each）： normal control group （NC）, uncontrolled diabetic group （DM1）, poorly-controlled diabetic group （DM2）, and well-controlled diabetic group （DM3）. Diabetic rats were induced by single intraperitoneal injection of streptozotocin, and the focal ischemic rat model of middle artery occlusion （MCAO） was made by insertion of fishing thread in 6 weeks after the establishment of the diabetic model. Each group was divided into 5 subgroups （10 rats each）： four focal ischemic subgroups at different ischemic-reperfusion time （at 3,12, 24 and 72 hours after reperfusion, respectively） and one sham-operated subgroup. The mRNA and protein expression of GLUT1 and GLUT3 was assessed by RT-PCR and Western blotting, respectively. Results There was significant difference in the mRNA expression of GLUT1 and GLUT3 between the four focal ischemic subgroups and the sham-operated subgroup at different reperfusion time in each group. The mRNA expression of GLUT1 and GLUT3 in the 4 ischemic groups began to increase at 3 hours, peaked at 24 hours after reperfusion and maintained at a higher level even at 72 hours compared with that of the sham-operated subgroup. The mRNA expression of GLUT1 increased more significantly than that of GLUT3. The mRNA expression of GLUT1 and GLUT3 was significantly different between the diabetic groups and normal control group. The mRNA expression of GLUT1 and GLUT3 was increased more significantty in the diabetic groups than that in the normal control group. There was a significant difference in the mRNA expression in the groups with different blood glucose levels. The mRNA expression tended to decrease with increased blood glucose levels. The expression trend of GLUT1 and GLUT3 protein was similar to that of GLUT1 and GLUT3 mRNA. Conclusions GLUT1 and GLUT3 expression was notably up-regulated in the penumbra region after cerebral ischemia in this study. But the up-regulated amplitude of GLUT1 and GLUT3 in the diabetic rats with cerebral ischemic injury became smaller than that of the normal controls. In the treatment of diabetic patients with cerebral embolism, blood glucose control should not be too strict, otherwise the up-regulation of GLUT1 and GLUT3 induced by cerebral ischemic injury might not be able to meet the needs of energy metabolism in cells. Chin Med J 2009; 122（ 17）： 1996-2001     

电针对局灶性脑缺血再灌注大鼠脑细胞凋亡及神经功能恢复的影响

Objective To investigate the influence of acpuncture on free calcium in rat brain cells after focal cerebral ischemia reperfusion.Methods 145 adult male SD rats were randomly divided into control group,simple ischemia reperfusion group and acupuncture with ischemia reperfusion group.The middle cerebral artery occlusion/reperfusion (MCAO/R) rat model was established by the modified Longa occlusion method. ①The part of free calcium in rat brain cells,focal cevebral ischemia model of rats were made by thread locking up the blood vessel for 15 min.30 min later after reperfusion, the Baihui and Shuigou Point in Du meridian were acupunctured electrically 30 min.After 3h, 6h and 12h, the rat was killed and its brain cells were made into single cell suspension,marked by Fluo-3/AM.The fluorescence optical density was recorded by laser confocal microscopy.②The part of nerve functional reconstruction, focal cevebral ischemia model of rats were made by thread locking up the blood vessel for 12 hours.30 min later after reperfusion, the Baihui and Shuigou Point in Du meridian were acupunctured electrically 30 min.After 7 d, 14 d,30 d,60 d and 90 d, the rat was forced to detect it's strength of the dog.Results ①Free calcium in rats of acupuncture therapy group(6h:10.96±1.18;2h:20.9±4.37) was significantly less than that in control group in 6 h and 12 h after reperfusion (6 h: 16.87 ± 3.56,12 h: 34.10 ±1.06)(P<0.05).②The dog in rats of acupuncture therapy group was significantly more than that in control group in 7 d, 14 d after reperfusion (P＜ 0.05 ).No difference of the dog was detected in 30 d ,60 d and 90 d after reperfusion between the two groups.Conclusion Acupunture could decreases the concentration of free calcium and the expression of Caspase-3 mRNA in rat brain cells after focal cerebral ischemia reperfusion, and it can facilitate the recovery of nerve function.     

线栓法大鼠局灶脑缺血模型的改进与评价

目的 评价改进后的线栓法大鼠永久性大脑中动脉阻塞局灶脑缺血模型(PMCAO)的使用价值.方法 SD大鼠随机分为3组,即正常对照组(n=8)、假手术组(n=8)、脑缺血组(n=16);脑缺血组分别取术后6 h、24 h为观察点,每个时间点各8只大鼠.通过改进颈部血管暴露方法、线栓进入技巧等实验技术,线栓法建立PMCAO后,2%红四氮唑溶液(TTC)染色观察各组缺血侧脑梗死变化和苏木素-伊红(H-E)染色观察各组缺血侧病理改变.结果 脑缺血组术后6 h、24 h脑缺血侧脑梗死和脑组织病理改变随时间加剧,而正常对照组和假手术组未见脑梗死和相应的病理改变.造模成功率达90%.结论 改进后的线栓法PMCAO方法操作简单,结果稳定可靠,重复性好,脑梗死与临床病理过程一致,是研究局灶脑缺血损伤比较理想、简易的实验动物模型.     

血液稀释对局部脑缺血大鼠脑血流及脑梗死的影响

为探讨中度急性等容血液稀释 (ANHD)对大鼠局部脑缺血模型的脑血流和脑梗死面积的影响 ,将Wistar脑缺血模型大鼠随机分为对照组 (n =8)和ANHD组 (n =8) ,于缺血前和缺血 1 2 0min内 ,用激光多普勒血流仪连续测定缺血周边皮质的局部脑血流 (LCBF)变化 ,缺血后 2 4h测定脑梗死面积。结果显示 2组在脑缺血后LCBF均显著下降 (P <0 .0 1 )。ANHD组下降的幅度显著小于对照组 (P <0 .0 1 ) ,并且缺血 2 4h后的脑梗死面积也显著小于对照组 (P <0 .0 5或P <0 .0 1 )。提示中度ANHD可增加大鼠局部脑缺血模型的缺血周边区的LCBF ,缩小脑梗死面积 ,在脑缺血情况下具有脑保护作用     

转笼康复训练对局灶性脑梗死大鼠旷场行为学和梗死灶周围Nogo-A表达的影响

目的 研究转笼康复训练对局灶性脑梗死大鼠旷场行为学和脑梗死灶周围皮质Nogo-A表达的影响。方法 将64只采用Longa颈外动脉线栓法制备的大脑中动脉闭塞SD大鼠随机分为康复训练组和造模对照组,每组32只。康复训练组大鼠每天进行滚筒训练40min;造模对照组置于普通笼中自由活动。康复训练组、造模对照组分别于造模后7,14,21和28d4个时间点随机选取8只大鼠进行旷场实验行为学分析后处死,取脑组织进行免疫组织化学方法观察脑梗死灶周围皮质Nogo-A的表达。结果 康复训练组术后21d,28d旷场运动路程与造模对照组同时点相比差异具有统计学意义(P<0.05)。术后14d,21d,28d康复训练组大鼠脑梗死灶周围皮质Nogo-A阳性细胞数与造模对照组同时点比较,差异亦具有统计学意义(P<0.05)。结论 转笼康复训练能降低大鼠脑梗死灶周围Nogo-A的表达,减少其对神经轴突的抑制,促进脑梗死后的神经再生,增加中枢神经系统的修复能力。     

UCP5在大鼠局灶性脑梗死周边神经细胞中的表达变化

目的 探讨UCP5在大鼠局灶性脑梗死周边神经细胞中的表达变化.方法 线栓法制作大鼠左侧大脑中动脉永久性闭塞缺血模型.67只大鼠随机分为假手术组（n=7）和缺血组（n=60）,缺血组按缺血时间分成缺血6h、12h、1d、3d、7d五个亚组每组12只.采用2％ TTC染色和HE染色显示梗死灶,应用免疫组化方法观察各组大鼠脑内UCP5阳性反应神经细胞数量.结果 2％TTC染色显示,缺血组大鼠左侧大脑中动脉供血区域均可见不规则白色梗死灶;HE染色显示,缺血组大鼠左侧大脑皮质均可见坏死区域.假手术组左侧大脑皮质UCP5阳性细胞数为（1.32±1.49）个/视野,缺血6h组梗死灶周边为（3.66±3.01）个/视野,缺血12h组为（9.96±7.33）个/视野,缺血1d组为（21.06±14.36）个/视野,缺血3d组为（12.20±11.19）个/视野,缺血7d组为（6.08±1.93）个/视野.与假手术组比较,五个缺血亚组阳性细胞数均显著增高（P＜0.003）.缺血1d组分别与6h、12h、3d、7d组相比阳性细胞数显著增高（P＜0.003）.结论 大鼠局灶性脑梗死周边神经细胞UCP5的表达显著增高.随缺血时间延长UCP5表达呈现峰样改变,在缺血1d达到高峰,UCP5可能在脑梗死中发挥着脑保护作用.     

盐酸戊乙奎醚预处理对大鼠局灶脑缺血再灌注损伤及凋亡相关基因caspase-3的影响

目的:观察盐酸戊乙奎醚预处理对大鼠局灶脑缺血再灌注损伤的影响及作用机制。方法:将60只雄性SD大鼠随机分为 3 组(每组20只)。对照组（C组）：进行假手术操作,未使用线栓法建立局灶脑缺血模型;缺血-再灌注组（I-R组）：麻醉前30 min腹腔内注射生理盐水2.0 mg•kg^-1后,使用线栓法建立大鼠局灶脑缺血模型,缺血120 min后进行再灌注;盐酸戊乙奎醚预处理组（P组）：麻醉前30 min腹腔内注射盐酸戊乙奎醚2.0 mg•kg^-1后,用线栓法建立大鼠局灶脑缺血模型,缺血120 min后进行再灌注。氯化三苯基四氮唑(TTC)染色观察测定脑梗塞体积;HE 染色法观察大鼠海马神经细胞形态的变化;半定量RT-PCR法测定海马组织caspase-3 mRNA的表达水平。结果:与I-R组比较,P组脑梗塞体积显著减小（P< 0.05）;I-R组海马神经细胞发生严重损伤,细胞核固缩、浓染,P组海马神经细胞损伤显著减轻;I-R组和P组caspase-3 mRNA表达水平明显高于C组（P< 0.05）,但P组caspase-3 mRNA表达水平低于I-R组（P< 0.05）。结论：盐酸戊乙奎醚预处理可以显著改善大鼠局灶脑缺血再灌注后海马神经细胞损伤,从而对脑缺血再灌注损伤发挥保护作用,这种保护作用可能与盐酸戊乙奎醚抑制大鼠脑海马组织凋亡蛋白酶caspase-3 mRNA的表达有关。     

电针影响大鼠脑缺血再灌注后水通道蛋白4 (AQP4)的表达及其在血管周边的分布

 目的 研究电针干预大鼠脑缺血再灌注损伤时脑内水通道蛋白4 (aquaporin 4,AQP4)的表达与分布改变。 方法 选用SD雄性大鼠406只,分为正常对照组(n=40),脑缺血组(n=138),脑缺血+电针组(电针处理组,n=138)和脑缺血+假电针组(n=90)。利用线栓法制作大鼠大脑中动脉阻塞(middle cerebral artery occlusion,MCAO)模型,缺血1 h后实施脑血流再灌注。电针处理组在脑缺血开始后立即给予电针刺激,穴位选择“水沟”(GV 26)与“百会”(GV 20)。利用Western blot检测AQP4的蛋白表达水平,胶体金免疫电镜观察AQP4免疫阳性颗粒在血管周边的分布,常规焦油紫染色计算脑缺血后的脑梗死体积以及脑肿胀程度。神经行为学评估通过Garcia量表进行评分。结果 (1)再灌注24 h内,电针可下调因脑缺血而诱导的AQP4表达升高,再灌注后6 h和12 h分别是缺血组的0.63倍和0.72倍(P < 0.05);(2)与正常对照组相比,血管周边AQP4的免疫阳性颗粒在再灌注后6 h增多,在再灌注后24 h减少,电针干预组中血管周边AQP4的免疫阳性颗粒密度发生改变,其变化与缺血组相反,差异有统计学意义(P < 0.05);(3)电针减轻脑缺血后的脑梗死及脑肿胀,促进神经行为功能的恢复。结论 电针下调因缺血而导致的AQP4蛋白的表达升高,并动态改变其在血管周边的分布。电针对AQP4的调控作用可能与电针的神经保护作用机制相关。     

rhG-CSF联合胞磷胆碱处理对大鼠脑缺血再灌注后Bcl-2,Bax的影响

目的观察rhG-CSF、胞磷胆碱处理分别对大鼠大脑局灶性脑缺血再灌注损伤后Bcl-2和Bax表达规律的影响,明确rhG-CSF、胞磷胆碱对大鼠大脑局灶性脑缺血再灌注损伤后的脑保护作用,并探讨其脑保护作用的机制。方法 72只成年雄性wistar大鼠(230±10g),随机分为4组,模型组(n=18)、rhG-CSF给药组(n=18)、胞磷胆碱给药组(n=18)、rhG-CSF联合胞磷胆碱给药组(n=18)。每组又分为6h、24h、72h三个亚组。采用线栓法制备大鼠大脑中动脉局灶缺血再灌注模型,采用DNA原位末端缺口标记法(TUNEL)检测神经元凋亡;HE染色观察脑组织形态病理学变化;免疫组化法测定大鼠脑缺血再灌注不同时间Bax和Bcl-2的平均光密度值。结果与手术组相比,给药组均能改善脑缺血大鼠神经损伤症状,减轻脑缺血再灌注的病理损伤,减少凋亡表达,增加Bcl-2,减少Bax的表达。且联合用药组与rhG-CSF组、胞磷胆碱组比较,各时间点Bcl-2的增加与Bax的减少,差异有统计学意义。结论 rhG-CSF、胞磷胆碱能减轻脑梗死后细胞凋亡,其机制可能与上调Bcl-2,降低Bax表达有关,联合用药治疗效果优于单独用药。     

半结扎脑表面动脉构建大鼠局灶性淋巴滞留性脑病动物模型

目的通过半结扎脑表面动脉的方法,构建一种局灶性淋巴滞留性脑病动物模型,观察血管周围间隙(VRS)扩张情况。方法 30只SD雄性大鼠,分为24 h模型组、48 h模型组和假手术对照组(每组各10只)。模型组采用脑表面动脉半结扎术造成局部淋巴回流障碍,术中监测大鼠脑电图变化;假手术组大鼠仅开颅分离脑表面动脉而不行半结扎。假手术组于术后48 h,24 h模型组和48 h模型组分别在术后24和48 h灌注固定并取脑进行冰冻切片,HE染色后在光镜下观察VRS扩张情况,采用Mias2000图像分析系统分别对24 h和48 h模型组以及假手术组的VRS截面积进行定量测量,并进行统计分析。结果脑电图监测显示术后大鼠未出现脑缺血等脑功能障碍改变。半结扎的脑表面动脉支配区域的皮层及皮层下均可见明显扩张的VRS,皮层下白质较多见。扩张的VRS周围脑组织结构疏松,着色浅淡。24 h模型组和48 h模型组半结扎的脑表面动脉支配区域的VRS面积显著大于假手术组(P<0.01),模型组之间无显著差异。结论采用脑表面动脉半结扎术能够有效构建大鼠局灶性淋巴滞留性脑病动物模型,手术创伤小、操作方便,制备的动物模型较稳定,为研究脑内淋巴循环障碍提供了一个较理想的平台。     

远隔后适应对大鼠脑组织中淀粉样前体蛋白表达的影响

目的研究远隔缺血后适应对大鼠脑缺血再灌注损伤后存在于神经元和神经胶质细胞中的淀粉样前体蛋白(β-amyloid precursor protein,β-APP)的影响。方法应用线栓法制作大鼠大脑中动脉闭塞缺血模型,缺血即刻和再灌注即刻分别给予肢体缺血后适应。应用双侧股动脉夹闭10 min/放开10 min,反复3次进行肢体缺血后适应。实验分为7组:假手术组,单纯缺血再灌注组(4 h、24 h组),缺血再灌注+缺血即刻远隔缺血后适应组(4、24 h组),缺血再灌注+再灌注即刻远隔缺血后适应组(4 h、24 h组),每组4只大鼠。采用免疫荧光方法观察β-APP蛋白表达的部位;采用免疫印迹方法研究β-APP的蛋白表达水平。结果脑缺血组大鼠缺血脑组织β-APP蛋白表达在缺血后不同时间点与假手术组比较差异无统计学意义。但是,可以看出β-APP在大鼠缺血后4 h无升高,缺血后24 h开始升高。给予远隔缺血后适应组与单纯缺血组比较,24 h时缺血即刻给予远隔后适应组,β-APP蛋白水平显著低于对照组(P<0.05)。结论远隔缺血后适应可能会通过降低脑缺血后β-APP蛋白表达水平,从而减轻脑缺血损伤。     

MK-801对局灶性脑缺血再灌注大鼠细胞增殖的影响

目的 研究MK-801对局灶性脑缺血再灌注大鼠神经干细胞增殖的影响.方法 60只雄性SD大鼠,随机分为正常时照组(n=6)、假手术组(n=6)、手术组(n=12)和手术MK-801不同浓度干预组(0.2、0.4、0.6、0:8、1.0和1.2 mg/kg n=36).用线栓法建立大脑中动脉缺血再灌注模型,在模型制作前30 min按照不同浓度组的剂量腹腔注射MK-801,假手术组和手术对照组腹腔注射等量的生理盐水.在模型建立后第7天,通过免疫组化技术标记大鼠梗塞区大脑皮质的Brdu阳性细胞数目.结果 MK-801浓度为0.4mg/kg时,可以明显抑制内源性神经干细胞的增殖,0.8ms/ks剂量以上有显著的抑制作用,并且随着浓度升高抑制作用呈递增趋势.结论 NMDA受体拮抗剂MK-801在局灶性脑缺血后对大鼠内源性神经干细胞的增殖有抑制作用,并且随浓度的增加抑制作用增强.