Pretreament with repeated electroacupuncture induced neuroprotection against spinal cord ischemiareperfusion injury in rabbits

AIM:To investigate whether pretreatment with repeated electroacupuncture (EA) could induce ischemic tolerance against transient spinal cord ischemia in rabbits.METHODS:24male New Zealand white rabbits were randomly assigned to 3 groups(n=8 each),animals in the control group received no treatment;animals in the SP and EA group received sodium pentobarbitone 30mg/kg each day for 5 days;animals in EA group were also received electroacupuncture at the Zusanli acupoint 30min a day for 5days.24hours after the last treatment,spinal cord ischemia was induced by an infrarenal aortic occlusion for 20min.Hind-limb motor function was determined with the Tarlov criteria at 4,8,12,24 and 48h after reperfusion.All animals were sacrificed at 48h after reperfusion and the spinal cords(I5) were remoed immediately for histopathologic study.RESULTS:The neurologic outcome and histopathology(48h) in the EA group were significantly better than the control group(P=0.006).CONCLUSION:Pre-ischemic treatment with electroacupuncture significantly reduces spinal cord ischemia-reperfusion injury in rabbits.     

Electro-acupuncture up-regulates the expression of stromal cell-derived factor-1α mRNA and its protein and promotes revascularization in the brain after focal cerebral ischemia and reperfusion

Objective To investigate the mechanism by which electro-acupuncture (EA) promotes revascularization in the brain after focal cerebral ischemia and reperfusion.Methods The Sprague-Dawley rat model of focal cerebral ischemia was made by filament occlusion. The rats were randomly divided into a control group, a model group, and an EA group. The model and EA groups were each divided into 5 subgroups receiving reperfusion 1, 3,7, 14 or 21 days after ischemia. EA was given at the bilateral Hegn point (LI 4) in the EA group. The expression of stromal cell-derived factor-1α(SDF-1α) mRNA was detected using a RT-PCR in the 3, 7 and 14 day subgroups.The immunohistochemical method was employed to detect the expression of SDF-1α protein. Results Compared with the control group, expression of SDF-1α protein increased significantly in the model and EA groups. Compared with the model group, the expression of SDF-1α mRNA increased significantly in the 3, 7 and 14 day subgroups.SDF-1α protein expression and microvessel count increased slightly but not significantly in the 1d subgroup, but the increases were significant in the 3, 7, 14 and 21 day subgroups.Conclusions EA may promote angiogenesis in an ischemic area of the cortex by increasing the expression of SDF-1αmRNA and its protein after focal cerebral ischemia and reperfusion.     

Electro-acupuncture up-regulates the expression of stromal cell-derived factor-1α mRNA and its protein and promotes revascularization in the brain after focal cerebral ischemia and reperfusion

Objective To investigate the mechanism by which electro-acupuncture (EA) promotes revascularization in the brain after focal cerebral ischemia and reperfusion.Methods The Sprague-Dawley rat model of focal cerebral ischemia was made by filament occlusion. The rats were randomly divided into a control group, a model group, and an EA group. The model and EA groups were each divided into 5 subgroups receiving reperfusion 1, 3,7, 14 or 21 days after ischemia. EA was given at the bilateral Hegn point (LI 4) in the EA group. The expression of stromal cell-derived factor-1α(SDF-1α) mRNA was detected using a RT-PCR in the 3, 7 and 14 day subgroups.The immunohistochemical method was employed to detect the expression of SDF-1α protein. Results Compared with the control group, expression of SDF-1α protein increased significantly in the model and EA groups. Compared with the model group, the expression of SDF-1α mRNA increased significantly in the 3, 7 and 14 day subgroups.SDF-1α protein expression and microvessel count increased slightly but not significantly in the 1d subgroup, but the increases were significant in the 3, 7, 14 and 21 day subgroups.Conclusions EA may promote angiogenesis in an ischemic area of the cortex by increasing the expression of SDF-1αmRNA and its protein after focal cerebral ischemia and reperfusion.     

脊髓损伤大鼠核因子kappa B与细胞凋亡及肢体功能间的相关性分析

Objective To investigate the relationship of nuclear factor kappa B(NF-κB),Bcl-2 and Bax with limb function after acute spinal cord injury in rats. Methods Forty-eight rats were divided at random into a control group and an experimental group with 24 rats in each.The spinal cords of the rats in the experimental group were injured at the T8,9,10 level through moderate compression.Four hours,8 h,and 1,3,7 and 14 days after the injury,4 rats were selected randomly from each group and graded with a BBB score.They were then sacrificed and their spinal cords were collected.Immunohistochemical measurements were used to observe the expression of NF-κB, Bcl-2 and Bax. Results NF-κB,Bcl-2 and Bax were observed in the injured spinal nerve cells of rats in the exper imental group but were absent in the control group.After injury,the expression of these factors increased at first and then decreased.BBB scores for limb function increased gradually.No correlation was found between the changes in NF-κB and Bcl-2,but the expression of NF-κB was positively correlated with that of Bax.There was negative correla tion between NF-kB levels and BBB scores,and between NF-kB levels and the ratio of Bcl-2 to Bax. Conclusion In rats,there is a close negative correlation between NF-kappa B levels,the ratio of Bcl-2/Bax and limb function after acute spinaI cord iujury.     

Effects of Electro-acupuncture Preconditioning on Focal Cerebral Blood Flow in Artery and Vein of Rats with Middle Cerebral Artery Occlusion

Abstract Objective：To investigate the effects of electro-acupuncture preconditioning on focal cerebral blood flow (CBF) in artery and vein of rats with middle cerebral artery occlusion(MCAO), and to provide experimental evidences for primary prevention of ischemic stroke. Method：Eighteen male Sprague-Dawley rats (two months old) were divided into 3 groups: electro-acupuncture preconditioning group (EA group), ischemia group (Is group) and Dazhui and Baihui sham group (six rats per group). The rats in the EA group were given electro-acupuncture preconditioning at Dazhui and Baihui with 2/15 density wave current for 30 minutes per day, 5 days consecutively. After preconditioning, enhanced laser speckle contrast analysis was implemented to get false color images before making middle cerebral ischemia occlusion model. Then getting false color images two hours during ischemia by laser speckle contrast analysis again. Result：①Relative CBF in focal cortical artery: There were significant differences at every time point in EA group and Is group (P<0.01, P<0.05) comparing with that before occlusion respectively. Compared with that before ischemia, there was significant difference at 120 min after ischemia in sham group (P<0.05); compared with that at 30 min after occlusion, there was significant difference at every time point in EA group from the time point 60 min after occlusion; there was significant difference at every time point in EA group and Is group (P<0.05) comparing with sham group; Compared with sham group, there was significant difference at 30 min and 60 min after ischemia in EA group (P<0.05). ② Relative CBF in focal cortical vein: There was significant difference at every time point in sham group comparing with that before occlusion (P<0.05); compared with that before occlusion, there was significant difference from 45 min after occlusion in EA group (P<0.05); compared with that before occlusion, there was significant difference from 105 min after occlusion in sham group (P<0.05); there was significant difference at 120 min after occlusion comparing with 60 min after occlusion in EA group; compared with sham group, there was significant difference at every time point in EA group and Is group (except 30 min after occlusion) (P<0.05), respectively; compared with Is group, there was significant difference at 30, 45, 60 min after occlusion in EA group (P<0.05). ③ The infarct brain volume detected 24 h after reperfusion in EA group was significantly smaller comparing with that in Is group (P<0.05). Conclusion：Electro-acupuncture preconditioning could increase CBF velocity in artery and vein of focal cortex in rats with MCAO, which also had time-dependence. Additionally, electro-acupuncture preconditioning could decrease the infarct volume detected 24h after reperfusion, which possibly was correlated with the blood supply in ischemic penumbra.     

丹参预防脊柱外科术后脊髓缺血再灌注损伤的疗效观察

Objective To investigate the effect of salvia mihiorrhiza on spinal cord ischemia reperfusion injury after surgical treatment in patients with cervical canal stenosis. Methods Retrospective analysis of 64 cases had cervical canal stenosis in the last 5 years in our hospital. Sixty-four cases were randomly divided into the salvia mihiorrhiza group(31 cases)and the control group(33 cases). The therapeutic effect was assessed using JOA grade system. Results In the salvia mihiorrhiza group,the JOA average score was 8. 8 ±2. 6 before surgical treatment, after two weeks of surgical treatment it was 13. 7 ± 2. 4. The JOA improvement ratio was (61. 5 ± 2. 9) % . In the control group,the JOA average score was 9. 1 ±2. 2 before surgical treatment,after two weeks of surgical treatment it was 13. 4 ± 2. 3. The JOA improvement ratio was (60. 5 ± 2.2)% .The JOA improvement ratio in the salvia mihiorrhiza group was significantly higher than that in the control group (P < 0. 05) . Conclusions Salvia mihiorrhiza has protective effect on spinal cord ischemia reperfusion injury.     

丹参预防脊柱外科术后脊髓缺血再灌注损伤的疗效观察

Objective To investigate the effect of salvia mihiorrhiza on spinal cord ischemia reperfusion injury after surgical treatment in patients with cervical canal stenosis. Methods Retrospective analysis of 64 cases had cervical canal stenosis in the last 5 years in our hospital. Sixty-four cases were randomly divided into the salvia mihiorrhiza group(31 cases)and the control group(33 cases). The therapeutic effect was assessed using JOA grade system. Results In the salvia mihiorrhiza group,the JOA average score was 8. 8 ±2. 6 before surgical treatment, after two weeks of surgical treatment it was 13. 7 ± 2. 4. The JOA improvement ratio was (61. 5 ± 2. 9) % . In the control group,the JOA average score was 9. 1 ±2. 2 before surgical treatment,after two weeks of surgical treatment it was 13. 4 ± 2. 3. The JOA improvement ratio was (60. 5 ± 2.2)% .The JOA improvement ratio in the salvia mihiorrhiza group was significantly higher than that in the control group (P < 0. 05) . Conclusions Salvia mihiorrhiza has protective effect on spinal cord ischemia reperfusion injury.     

Effects of Epidural Spinal Cord Stimulation and Treadmill Training on Locomotion Function and Ultrastructure of Spinal Cord Anterior Horn after Moderate Spinal Cord Injury in Rats

Objective:To investigate the effects of epidural spinal cord stimulation (ESCS) and treadmill training on the locomotion function and ultrastructure of spinal cord anterior horn after moderate spinal cord injury in rats.Method:Nine adult female Sprague-Dawley rats were randomly distributed into three groups: ①spinal cord injury group (SI, n=3). ②spinal cord injury plus ESCS group (SE, n=3). ③spinal cord injury plus treadmill training group (TT, n=3). All rats received a moderate spinal cord injury surgery. Four weeks after surgery, rats in SE group received an electrode implantation procedure, with the electrode field covering spinal cord segments L2—S1. Four weeks after electrode implantation, rats received subthreshold ESCS for 30 min/d. Rats in TT group received 4cm/s treadmill training for 30min/d. Rats in SI group received no intervention, as a control group. All procedures in these three groups lasted four weeks.The open field Basso,Beattie and Bresnahan(BBB) scale was used before and after intervention to evaluate rats′ hindlimb motor function. Result:After four weeks intervention, rats in TT group improved their open field locomotion scores to 20. In contrast, no significant improvement was observed in groups SI and SE. The morphology of synapses and neurons were similar regardless of whether rats had undergone ESCS, treadmill training or not. Conclusion:ESCS alone was not sufficient to improve the walking ability of spinal cord injured rats. ESCS or treadmill training alone might not contribute to the changes of ultrastructure in anterior horn of spinal cord that underlie the recovery of walking ability. Further research is needed to understand the contributions of combination of ESCS and treadmill training to the rehabilitation of spinal cord injured rats.     

抗栓药物联合治疗急性脑梗死

Objective To investigate the efficacy and safety of combinative antithrombotic therapy for patients with acute cerebral infarction who were not eligible for thrombolysis. Methods Eighty-three patients with acute cerebral infarction at six to twelve hours after the onset were randomly allocated into two groups : treat-ment group(n=46) recived batroxobin, aspirin and dipyridamole; control group(n=37) received aspirin. Neuro-logic impairment scole was measured at days 0, and 14. Barthel index of the two groups were observed at days 0 and 90. Blood coagulation action of the treatment group was also measured at days 0,5 and 11. Results In treatment group, the nervous function defect integral examined 14 d after trearment (12.7±6.4 )was markedly decreased than that of control group (20.1±7.2). A remarkable difference (P<0.01 ) was noticed between them. The Barthel index of the treatment group at 90 d after trearment (86.8±12.9 )was markedly increased than that of control group(43.4±15.1 ) (P<0.01 ). The total effective rate of treatment group and control group were 93.5% and 56.8% respectively( P<0.01). Conclusion The efficacy of combinative antithrombotic therapy for patients with acute cerebral infarction who were not eligible for thrombolysis is better than aspirin a-lone. Further more, the risk of bleeding may not increase in combinative antithrombotic therapy.     

纳洛酮对重复电针预处理诱导脊髓缺血耐受作用的影响

目的 :研究阿片肽在电针重复预处理诱导脊髓缺血耐受中的作用。方法 :4 0只雄性新西兰大白兔随机分成 5组 (n=8) :对照组、戊巴比妥钠组、纳洛酮组、电针预处理组和纳洛酮 +电针预处理组。对照组未行任何处理 ;戊巴比妥钠组每日静脉给予戊巴比妥钠 30 m g/ kg,连续 5 d;纳洛酮组每日静脉给予纳洛酮 0 .3mg/ kg,连续 5 d;电针预处理组每日在戊巴比妥钠 30 m g/ kg麻醉下 ,电针刺激双侧委中穴 6 0 min/ d,连续 5 d;纳洛酮 +电针预处理组预处理前 30 m in静脉注射纳洛酮 0 .3mg/ kg,余同预处理组。最后一次预处理后 2 4 h阻闭肾下腹主动脉 2 0 min,制备兔脊髓缺血模型 ;再灌注后 4 h、8h、12 h、2 4 h和 4 8h分别对动物后肢运动功能进行评分 ;再灌注 4 8h后深麻醉下处死动物取脊髓 (L 5～ L 7) ,制作标本并行组织病理学观察。结果 :所有动物都存活 ,再灌注 4 8h后电针预处理组动物后肢运动功能评分及脊髓前角运动神经元计数均明显高于纳洛酮 +电针预处理组 (P均 <0 .0 1) ,对照组、戊巴比妥钠组、纳洛酮组及纳洛酮 +电针预处理组间后肢运动功能评分及脊髓前角运动神经元计数均无显著性差异 (P均 >0 .0 5 )。结论 :重复电针预处理对兔脊髓缺血再灌注损伤的保护作用可被纳洛酮阻断 ,提示阿片肽参与了电针预处     

不同穴位重复电针预处理诱导兔脊髓缺血耐受效果的对比

目的:比较不同穴位电针预处理对兔脊髓缺血再灌注损伤保护作用的效果,为临床提供最佳的预处理方案。方法:32只雄性新西兰大白兔随机数字表法分成4组(各组n=8),即对照组、戊巴比妥钠组、委中穴组及足三里穴组。对照组静脉给予生理盐水1mL/kg,连续5d;戊巴比妥钠组静脉给予戊巴比妥钠30mg/kg,连续5d;委中穴和足三里穴组每天在戊巴比妥钠(30mg/kg)麻醉下,电针分别刺激委中穴和足三里穴60min/d,连续5d。最后一次预处理后24h,夹闭肾下腹主动脉20min,制作兔脊髓缺血模型;再灌注后4,8,12,24和48h分别对动物后肢运动功能评分;再灌注48h后,深麻醉下处死动物取脊髓(L5～7),制作标本行组织病理学观察。结果:所有动物均存活,再灌注后48h电针预处理委中穴和足三里穴组后肢运动功能评分及脊髓前角运动神经元计数均明显高于对照组(P=0.001);足三里组后肢运动功能评分和脊髓前角运动神经元计数明显低于委中穴组(P=0.001);对照组与戊巴比妥钠组相比,后肢运动功能评分及脊髓前角神经元计数无显著性差别(P=1.0和P=0.873)。结论:电针预处理对兔脊髓缺血再灌注损伤有显著的保护作用,且刺激委中穴优于刺激足三里穴的效果。     

远程预处理对兔脊髓缺血再灌注损伤的保护作用(英文)

目的:探讨远程预处理对兔脊髓缺血再灌注损伤的保护作用。方法:20只成年雄性新西兰大白兔随机分成2组(各组n=10),即对照组和远程预处理(RPC)组。所有动物脊髓缺血前1h戊巴比妥钠麻醉动物(30mg/kg,iv)。RPC组动物麻醉后进行双后肢短暂缺血2次(充气式压力止血带环扎双后肢,压力26.6kPa,阻断10min,松开10min,再阻断10min),最后一次缺血后再灌注30min,阻闭肾下腹主动脉20min,制作兔脊髓缺血模型。对照组动物不进行双后肢短暂缺血,其余同RPC组。再灌注后4,8,12,24和48h分别对动物后肢运动功能评分。再灌注48h后,处死动物取脊髓(L5～7),石蜡包埋切片行组织病理学观察。结果:RPC组神经功能评分在各时间点均明显高于对照组(P=0.000);与对照组相比,RPC组脊髓前角正常神经细胞数明显增多(P=0.000),且神经功能评分与脊髓前角正常神经细胞计数之间有显著相关性(r=0.868,P<0.01)。结论:远程预处理对兔脊髓缺血再灌注损伤有显著的保护作用。     

硫酸镁对兔脊髓缺血再灌注损伤的保护

背景硫酸镁用于脑缺血再灌注损伤的治疗已取得了较满意的疗效,但对脊髓缺血再灌注损伤的作用机制尚不十分清楚.目的观察硫酸镁对兔脊髓缺血再灌注损伤的保护效果,进一步探讨其作用机制.设计以实验动物为研究对象,随机对照的重复测量设计.单位一所大学医学院中心实验室.对象实验于2003-04/2004-06在西安交通大学医学院中心实验室完成.健康成年新西兰大白兔27只,体质量1.9～2.5 kg.随机抽签法分为硫酸镁组、生理盐水组和假手术组,每组9只.方法夹闭腹主动脉肾下段30min后恢复血流再灌注48 h,建立兔脊髓腰骶段缺血模型.硫酸镁组给予静脉灌注硫酸镁(0.25 mL/kg·h),生理盐水组用等量生理盐水代替.假手术组仅行中线剖腹术,不结扎动脉.在缺血前,缺血30 min及再灌注后1,2,8,16,24 h对动物行体感诱发电位监测,再灌注24及48 h后对硫酸镁组、生理盐水组动物行运动功能评分.再灌注后48 h处死动物,对脊髓行组织病理学检查.主要观察指标①运动功能评分.②体感诱发电位监测.③脊髓组织病理学检查.结果缺血30 min时硫酸镁组体感诱发电位(N1)潜伏期明显延长;再灌注后前2 h潜伏期较缺血时明显恢复,其后又显著延长.缺血30 min时生理盐水组波形消失.假手术组体感诱发电位没有明显变化,动物均完全康复.硫酸镁组各时间点潜伏期恢复均明显高于生理盐水组(P＜0.05);再灌注24和48 h后,硫酸镁组的神经功能评分分别为(3.7±0.5)和(3.4±0.7)分,均显著高于生理盐水组[(3.0±0.7)和(2.6±0.9)分](P＜0.05);再灌注48 h后硫酸镁组的脊髓前角正常神经细胞计数显著高于生理盐水组(23.4±3.4,12.3±3.2,P＜0.01).结论硫酸镁具有减轻兔脊髓缺血再灌注损伤及保护神经功能的作用.     

电针对心肌缺血再灌注损伤家兔心肌细胞凋亡的影响

目的:研究电针对心肌缺血再灌注损伤家兔心肌细胞凋亡的影响.方法:将结扎左冠状动脉前降支30 min,再灌注60 min,成功制作为心肌缺血再灌注损伤模型的家兔24只,随机分为模型组、电针1及2组各8只.另仅开胸未结扎冠状动脉的8只为假手术组作为正常对照.电针1、2组术后30 min分别采用电针针刺内关穴与列缺穴60 min,仅1次,应用原位末端标记法观察4组家兔心肌细胞凋亡情况.结果:心肌凋亡细胞数量,模型组显著高于假手术组(P＜0.01),电针1组与电针2组、模型组比较显著降低(P＜0.05,P＜0.01),但仍高于假手术组(P＜0.01).结论:细胞凋亡参与心肌缺血再灌注损伤的病理过程,电针内关穴可以减少缺血再灌注损伤心肌细胞凋亡的数量,从而达到抗缺血再灌注损伤的作用.     

Protective effects of trimetazidine in transient spinal cord ischemia

The neuroprotective effect of trimetazidine (TMZ) was tested prospectively in a rabbit spinal cord ischemia model. Ischemia was induced by clamping the aorta just distal to the left renal artery and proximal aortic bifurcation for 20 min. Twenty-five male New Zealand white rabbits were randomized as follows: TMZ group (n=10) receiving 3 mg/kg trimetazidine intravenously before the occlusion of the aorta; control group undergoing occlusion but receiving no pharmacologic intervention (n=10); sham-operation group (n=5) subjected to operative dissections without aortic occlusion. Physiological parameters and somatosensory evoked potentials (SEP) were monitored in animals before the ischemia, during the ischemia and in the 1st, 15th and 60th min of reperfusion. Neurologic status was assessed 24 and 48 h after the operation. The spinal cord, abdominal aorta, and its branches were processed for histopathologic examinations 48 h after the operation. At the end of the ischemic period, the average N1-P1 amplitude was reduced to 22% of the baseline in all ischemic animals. This was followed by a gradual return to 90DŽ% of the initial amplitude in the TMZ group and 81DŽ% in the control group (P<0.05) after 60 min of reperfusion. The average motor function score was significantly higher in the TMZ group than the control group (3.7ǂ.5 vs 3.1ǂ.6 at 24 and 3.5ǂ.7 vs 2.9ǂ.6 at 48 h; P<0.05). Histologic observations were clearly correlated with the neurologic findings. The results suggest that trimetazidine reduces spinal cord injury during thoracoabdominal aortic operations and may have therapeutic utility during high risk operations.     

重组人促红细胞生成素对兔脊髓缺血/再灌注损伤后白细胞介素8表达的影响

目的探讨重组人促红细胞生成素(rHuEPO)对兔脊髓神经细胞缺血/再灌注损伤后白细胞介素8(IL-8)表达的影响。方法 44只健康成年新西兰大白兔随机分为3组:假手术组(4只),对照组(20只),rHuEPO处理组(20只),对照组与rHuEPO处理组分别于再灌注6 h,12 h,24 h、48 h、7 d后时间点随机处死4只动物,取L3～L5节段脊髓组织用霉菌抗生物素蛋白-过氧化酶免疫组化染色法(S-P法)及兔抗人IL-8 ELISA试剂盒检测脊髓组织内IL-8的表达。结果 IL-8在无损伤脊髓中即见有表达。随着缺血及再灌注进程的加重,组织中IL-8阳性表达强度逐渐增加。脊髓损伤后24 h表达明显上调并达高峰;高表达持续至损伤后7 d;两组间IL-8水平的变化趋势相同,但在各时间点rHuEPO处理组兔脊髓组织IL-8的含量均低于对照组(P<0.05)。结论 rHuEPO具有抑制脊髓组织炎症反应的作用,能明显抑制兔脊髓缺血/再灌注损伤后的IL-8表达。     

重复高压氧预处理对兔短暂脊髓缺血后线粒体结构及ATP酶活性的影响

背景重复高压氧预处理诱导脊髓对随后的缺血产生耐受,这一现象的证实为临床防治胸腹主动脉术后的脊髓缺血并发症开辟了新的道路.探讨其缺血耐受性产生的机制无疑将为这一方法的临床应用奠定基础.目的探讨重复高压氧预处理诱导脊髓缺血耐受中线粒体结构及ATP酶活性变化.设计随机对照实验. 单位解放军第四军医大学西京医院麻醉科.材料实验于2004-03/06在第四军医大学空医系高压氧舱及西京医院麻醉科实验室完成.选用雄性新西兰大白兔50只.方法50只雄性新西兰大白兔随机分为两组单纯缺血对照组,重复高压氧预处理组0.25 MPa,100%O2,1 h/d,5 d.每组25只.最后1次预处理后24 h制作脊髓缺血模型.采用肾下腹主动脉阻断法造成脊髓缺血(20 min)/再灌注模型,观察动物再灌注6,24和48 h后肢神经运动功能评分,分别于缺血前、再灌注6,24和48 h处死动物并提取线粒体测定ATP酶活性.主要观察指标①各组动物后肢运动神经功能评分.②各组动物脊髓线粒体ATP酶活性.③各组动物病理学评估.结果纳入分析50只,最终进入统计分析的大白兔保持为2组,各25只,无缺失值.①后肢运动神经功能评分再灌注6,24和48 h高压氧预处理组神经功能评分明显高于对照组(P＜0.01).②脊髓线粒体ATP酶活性两组动物再灌注后各时间点线粒体Na+,K+-ATP酶活性和Ca2+,Mg2+-ATP酶活性均明显下降,高压氧预处理组Na+,K+-ATP酶活性在再灌注6,24h和48 h明显高于对照组(P＜0.01);Ca2+,Mg2+-ATP酶活性在再灌注6 h和24 h明显高于对照组(P＜0.01).③病理学评估电镜下观察再灌注48 h时的组织切片,对照组线粒体空泡化明显,高压氧预处理组多数线粒体结构接近正常.结论高压氧预处理诱导脊髓缺血耐受产生的机制部分可能是通过减慢线粒体ATP酶活性下降,维持线粒体功能实现的.     

氨基胍对兔脊髓缺血再灌注损伤的保护作用

目的：研究氨基胍对兔脊髓缺血再灌注损伤的保护作用。方法：在左肾动脉下方夹闭腹主动脉30min后恢复血流灌注,建立兔脊髓腰骶段缺血再灌注损伤模型。18只新西兰大白兔随机分为假手术组（A组,n=4）、缺血再灌注组（B组,n=7）和氨基胍治疗组（C组,n=7）。C组在夹闭动脉前静脉注射氨基胍（100mg.kg-1）,术后8h再肌肉注射氨基胍（100mg.kg-1）1次。术后24h对兔后肢运动功能进行评分,观察脊髓病理改变情况,检测脊髓一氧化氮（NO）含量和一氧化氮合酶（NOS）活性,TUNEL法检测脊髓细胞凋亡,免疫组织化学染色测定Bax与Bcl-2蛋白表达情况。结果：缺血再灌注后24h,与缺血再灌注组相比,氨基胍治疗组兔后肢运动功能明显改善,脊髓内NO含量和NOS活性下降（P〈0.05）,脊髓细胞凋亡指数下降（P〈0.05）,Bax蛋白表达下降（P〈0.05）,Bcl-2蛋白表达升高（P〈0.05）,脊髓损伤病理改变明显减轻。结论：氨基胍对兔脊髓缺血再灌注损伤有保护作用,其机制与抑制iNOS活性有关,并且可以通过调节Bax、Bcl-2蛋白表达抑制脊髓细胞凋亡。