Reliability of pressure cuff induced transient limb ischemia in conscious rabbits

Background The protective effects of transient limb ischemia （TLI） induced by several cycles of intermittent pressure cuff inflation and deflation for a period have been widely investigated,however the reliability of this protocol has not been clearly verified.Our study aimed to investigate the reliability of pressure cuff induced TLI in conscious rabbits.Methods Eight New Zealand rabbits were subjected to TLI without anesthesia.TLI consisted of 3 cycles of ischemia and reperfusion induced by inflating the cuff placed on the left lower limb to 200 mmHg for 5 minutes followed by deflating the cuff for 5 minutes.Skin color,pulse oxygen saturation （SpO2）,pulse rate （PR）,plethysmogram waveform （Pleth）,and ultrasound detection of the blood flow in the extremity distal to the ischemic segment were observed to confirm ischemia and reperfusion during TLI.The frequency of severe limb movement during TLI was also recorded to assess the amenability of this protocol in conscious rabbits.Results The skin color of the extremity distal to the ischemic segment changed from bright red to dark purple after inflating the cuff to 200 mmHg,and returned to normal after cuff deflation.Pleth,PR and SpO2 disappeared during ischemia and restored during reperfusion in the monitor.Blood flow of the left posterior tibial artery was completely blocked by a pressure of 200 mmHg during ischemia,and recovered immediately after cuff deflation.The frequency of severe limb movement in supine position was higher than that in prone position （P〈0.05）,but there was no severe limb movement that could result in disturbance to ischemia when the rabbits were placed in prone position.Conclusion Pressure cuff inflating to 200 mmHg for 5 minutes and deflating for 5 minutes is a reliable regimen to induce TLI in conscious rabbits.     

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。     

Ischemic postconditioning alleviates lung injury and maintains a better expression of aquaporin-1 during cardiopulmonary bypass

Background It has found that ischemic postconditioning （IPO） might decrease pulmonary ischemia/reperfusion （I/ R） injury,which is one of the main reasons of lung injury caused by cardiopulmonary bypass （CPB）.It was found that aquaporins （AQPs） play a role in the maintenance of fluid homeostasis.But it is still unclear whether IPO influences the expression of aquaporin-1 （AQP1）.This study was designed to investigate whether IPO can reduce CPB-related lung injury and affect the expression of AQP1 of lungs.Methods Twelve healthy dogs were divided into control group （C group） and ischemia postconditioning group （IPO group）.CPB procedures were implemented.Ten minutes later,the left pulmonary artery was separated and blocked.Postconditioning consisted of two cycles of 5-minute pulmonary artery reperfusion/5-minute reocclusion starting at the beginning of reperfusion.The 2×4 cm tissues of both sides of pulmonary apex,superior,middle and inferior lobe were taken before CPB （T1）,before occlusion and reopening of left pulmonary artery （T2,T3）,and 2 hours after CPB （T4）.Samples were used to evaluate lung injury degrees and to detect the expression of AQP1.At T1 and T4,blood was collected from femoral artery to calculate pulmonary function.Results At T4,each pulmonary function showed significant deterioration compared with T1.Lung injury could be found at the onset of CPB.However,the expression of AQP1 decreased and wet to dry weight ratio （W/D） increased after T2.In the left lung of C group,the worst pulmonary function and structures were detected.The slightest changes were discovered in the right lung of C group.A close relationship between W/D and lung injury score was found.The lung injury score was negatively related with the expression of AQP1.It was found that the expression of AQP1 was negatively connected with W/D.Conclusions In dog CPB models,lung injury induced by CPB was related with down regulated expression of AQP1.AQP1 is believed to be involved in the mechanisms of     

自噬在缺血预处理减轻大鼠肢体缺血再灌注心肌损伤中的作用

目的 探讨自噬在缺血预处理减轻大鼠肢体缺血再灌注心肌损伤中的作用。 方法 雄性SD大鼠28只,8周龄,体重200~250 g,采用随机数字表法,将其分为4组(n_i=7):假手术组(S组)、肢体缺血再灌注组(IR组)、肢体缺血预处理组(IPR组)、自噬抑制剂处理组(3-MA组)。采用夹闭双侧股动脉缺血4 h后恢复灌注4 h的方法建立肢体缺血再灌注模型;采用股动脉夹闭前30 min实施缺血5 min,再灌注5 min,循环3次后建立肢体缺血预处理模型;3-MA组于缺血预处理前30 min腹腔注射3-甲基腺嘌呤1.5 ml/kg。再灌注4 h后处死大鼠取心肌组织,电镜下观察自噬小体形成情况和病理学结果,采用HE染色和TUNEL法检测心肌细胞凋亡情况,采用Western blot法检测LC3-Ⅱ的表达情况。 结果 与S组相比,IR组、IPR组、3-MA组心肌细胞凋亡比例明显升高,LC3-Ⅱ/LC3-Ⅰ表达上调(P<0.05);与IR组相比,IPR组细胞凋亡降低、LC3-Ⅱ/LC3-Ⅰ表达下调(P<0.05);与IPR组相比,3-MA组细胞凋亡比例升高、LC3-Ⅱ/LC3-Ⅰ表达下调(P<0.05)。 结论 自噬参与了肢体缺血预处理减轻大鼠肢体缺血再灌注心肌损伤的作用。      

Angiogenesis effect of Astragalus polysaccharide combined with endothelial progenitor cells therapy in diabetic male rat following experimental hind limb ischemia

Background Diabetes mellitus （DM） is a common disease accompanied with a high incidence of hind limb ischemia （HLI）.In recent years,numerous studies demonstrated that endothelial progenitor cells （EPCs） are involved in angiogenesis and maintenance of vascular integrity following HLI.On the other side,it has been proved that Astragalus polysaccharide （APS） could promote angiogenesis.In the present study,we aimed to evaluate the effect of APS and EPCs on enhancing angiogenesis after experimental HLI caused by femoral artery ligation in rats with streptozotocin （STZ）-induced diabetes.Methods Rats （n=110） were randomly assigned to the following groups：sham group,ischemia group,APS group,EPCs group and APS＋EPCs group.APS,EPCs or an equal volume of vehicle was administered intramuscularly after HLI induction,and 6 rats were assessed by angiography at 28 days after induction of HLI,6 rats were sacrificed at the same time point to take histological studies,biochemical tests were also performed at that point in the rest rats.Results APS or EPCs treatment induced an increase,respectively,in the protein expression of vascular endothelial growth factor （VEGF） （36.61%,61.59%）,VEGF receptor-1 （VEGFR-1） （35.50%,57.33%）,VEGFR-2 （31.75%,41.89%）,Angiopoietin-1 （Ang-1） （37.57%,64.66%） and Tie-2 （42.55%,76.94%） （P 〈0.05）,after HLI injury.And combined therapy of APS and EPCs enhanced the effort of angiogenesis after HLI induction in diabetic rats,through elevating protein expression of VEGF （99.67%）,VEGFR-1 （105.33%）,VEGFR2 （72.05%）,Ang-1 （114.30%） and Tie-2 （111.87%） （P〈0.05）.Similarly,mRNA expression of VEGF,VEGFR-1,VEGFR2,Ang-1,Tie-2 also show similar trends as well as protein expression （P〈0.05）.Conclusion APS or EPCs could enhance angiogenesis,and the combined treatment leads to better effort,at least,partially via VEGFNEGFR and Ang-1/Tie-2 signaling pathway.     

缺血后处理对大鼠肢体缺血再灌注后肺损伤的保护作用及其机制

目的: 观察缺血后处理(I-postC)对大鼠肢体缺血再灌注(LIR)后肺损伤的影响,探讨I-postC的器官保护作用及可能机制。方法: 24只Wistar大鼠随机分为对照组、缺血再灌注组(IR组)和I-postC组(n=8)。橡皮带结扎动物双后肢根部4h后松解橡皮带恢复血流灌注4h,制作大鼠肢体缺血再灌注动物模型。对照组橡皮带松弛环绕大鼠双后肢根部,不阻断血流。I-postC组大鼠在血流再灌注前,行缺血5 min-再灌注5 min,重复3次,再恢复血流灌注4h。实验结束留取血液及肺组织标本,测定各组大鼠血液中性粒细胞CD18阳性细胞百分率、血浆可溶性细胞间黏附分子-1(sICAM-1)和P-选择素(P-selectin)水平以及肺组织髓过氧化物酶(MPO)活性、细胞间黏附分子-1(ICAM-1)和P-selectin水平,测定各组大鼠动脉血气指标氧分压(PaO₂)和二氧化碳分压(PaCO₂),光镜及电镜下观察各组大鼠肺组织的形态学改变。结果: 与对照组比较,IR组大鼠外周血中CD18阳性细胞百分率明显升高(P<0.01);血浆和肺组织中sICAM-1及P-selectin水平均升高(P<0.01);肺组织中MPO活性升高(P<0.01);PaO₂和PaCO₂明显降低(P<0.01)。IR组大鼠肺组织镜下可见肺间质内血管扩张、充血,中性粒细胞浸润,血管周间隙增大,肺泡间隔增宽,肺泡腔内有渗出液,支气管上皮细胞脱落坏死。与IR组比较,I-postC组上述生化指标检测值明显降低(P<0.01),PaO₂和PaCO₂明显升高(P<0.01);血浆及肺组织炎性因子活性降低(P<0.01);镜下可见肺组织损伤减轻。结论: I-postC可通过抑制炎症反应减轻大鼠LIR后的肺损伤。     

缺血预处理对肝缺血再灌注损伤肝实质细胞的影响

目的 通过观察缺血预处理对大鼠肝缺血再灌注损伤肝实质细胞凋亡影响,探讨肝缺血再灌注损伤机制及肝缺血预处理对肝细胞的保护作用.方法 35只Wistar大鼠,随机分为假手术 (SO)组5只;缺血再灌注3、6、24 h组(IR3 h、IR6 h、IR24 h)各5只;缺血预处理3、6、24 h组(IP3 h、IP6 h、IP24 h)各5只.IR组半肝缺血60 min,再灌注3、6、24 h;IP组为缺血前先行5 min缺血、5 min复流,并重复2次,然后行半肝缺血60 min,再灌注3、6、24 h.分别取材检测血清丙氨酸转氨酶(ALT)、肝组织匀浆丙二醛(MDA).结果IR各组血清ALT、肝组织匀浆MDA均较SO组有显著性升高(P<0.05);经缺血预处理后,ALT、MDA显著下降(P<0.05).结论肝脏缺血再灌注各时间点都有肝细胞损伤,且24 h内随着再灌注时间增加,;缺血预处理能够抑制肝细胞凋亡,减轻肝细胞再灌注损伤.     

氧化应激在大鼠肢体缺血再灌注后心肌损伤中的作用

①目的 观察大鼠肢体缺血再灌注(LIR)后心肌的损伤变化。②方法 将实验大鼠随机分为7组，即对照组(control)、缺血组(1)、缺血再灌注0．5小时组(R0.5)、2小时组(R2)、4小时组(R4)、6小时组(R6)、10小时组(R10)。分别测定血象及心肌组织中丙二醛(MDA)浓度和超氧化物歧化酶(SOD)水平，并测定心肌组织髓过氧化物酶(MPO)和血浆乳酸脱氢酶(LDH)活性。③结果 与对照组比较，MDA、LDH、MPO检测量在R0.5、R2、R4组依次增加，在R6、R10两组依次减少；SOD活性在R0.5、R2、R4组依次下降，在R6组有所恢复，至R10组又有所下降。④结论 大鼠肢体缺血再灌注(IR)后继发心肌损伤，可能与氧化应激有关。     

缺血后处理对大鼠肢体缺血再灌注后肾细胞凋亡的抑制作用

目的：观察缺血后处理对大鼠肢体缺血再灌注（LIR）后肾组织细胞凋亡的影响,探讨其可能机制。方法：30只SD大鼠随机分为对照组、缺血再灌注组（IR组）和缺血后处理加再灌注组（I-postC组）,每组10只。建立大鼠肢体缺血再灌注（LIR）模型,即橡皮带环绕大鼠双后肢根部阻断血流4h再恢复血流灌注4h。对照组大鼠仅松弛环绕橡皮带不阻断血流,I-postC组大鼠则在再灌注前附加反复3次缺血5 min-再灌注5 min操作,即缺血后处理。全自动生化分析仪测各组大鼠血浆肌酐（Cr）、尿素氮（BUN）和C反应蛋白（CRP）水平;免疫组织化学法检测大鼠肾组织凋亡相关蛋白Bcl-2和Bax的表达,采用自动图像分析系统统计其定量结果并计算Bcl-2/Bax比值;TUNEL染色后在激光共聚焦显微镜下观察肾组织细胞凋亡情况,电镜下观察肾组织超微结构。结果：与对照组比较,IR组和I-postC组大鼠血浆Cr、BUN和CRP水平均明显增高（P<0.01）;与IR组比较,I-postC组大鼠血浆Cr、BUN和CRP水平均明显降低（P<0.01）。与对照组比较,IR组和I-postC组大鼠肾组织中Bax和Bcl-2表达水平明显升高（P<0.05或P<0.01）,Bcl-2/Bax比值降低（P<0.05）;与IR组比较,I-postC组大鼠肾组织中Bax表达水平降低（P<0.05）,Bcl-2表达水平升高（P<0.01）,Bcl-2/Bax比值升高（P<0.05）。激光共聚焦显微镜下观察,与对照组比较,IR组大鼠肾组织中凋亡细胞明显增多;与IR组比较,I-postC组大鼠肾组织中凋亡细胞明显减少。透射电镜下观察,对照组大鼠肾组织细胞结构清晰完整;IR组大鼠肾组织中肾近曲小管上皮细胞核固缩,溶酶体和致密颗粒沉积增多,线粒体数目减少,部分线粒体嵴断裂或模糊,肾小球足突细胞突起不规则、融合,有空泡现象,粗面内质网扩张;与IR组比较,I-postC组大鼠肾组织中肾小管上皮细胞及肾小球损伤有一定程度改善。结论：LIR可诱发大鼠肾组织细胞凋亡,缺血后处理可抑制肢体缺血再灌注后的肾细胞凋亡,对改善大鼠肾功能有一定作用。     

大鼠肠缺血再灌注后肠黏膜细胞凋亡和内源性一氧化氮的观察

目的 通过观察大鼠肠缺血再灌注后肠黏膜细胞凋亡及血清一氧化氮(NO)浓度改变的情况，旨在为临床提供检测肠缺血再灌注损伤的指标。方法 成年雄性SD大鼠，夹闭肠系膜上动脉1h，再开放2h制成肠缺血再灌注的7只动物模型作为实验组；正常假手术大鼠5只为对照组。测定缺血前后及再灌注后的血清NO浓度、再灌注后肠黏膜细胞TUNEL染色的阳性细胞数，采用免疫组织化学ABC法检测半胱氨酸天门冬氨酸特异蛋白酶(Caspase—3)的表达水平。结果 实验组在缺血前清NO浓度与对照组的差异无显著性；缺血后及再灌注后明显下降(P＜0．05)，与对照组比较，差异有显著性。缺血再灌注后实验组肠黏膜细胞的凋亡增加，TUNEL染色阳性细胞数及Caspase—3平均灰度值均显著高于对照组(P＜0．01)。结论 大鼠肠缺血再灌注后血清NO浓度下降，肠黏膜细胞凋亡增加，可作为肠缺血再灌注的损伤指标，适用于临床辅助诊断并为治疗提供参考。     

亚低温对脑缺血再灌注损伤大鼠神经细胞凋亡和caspase-3释放的影响

目的 从信号转导及细胞凋亡角度,研究亚低温对大鼠脑缺血再灌注损伤(I/R)的脑保护作用及机制。方法 72只雄性健康SD大鼠,随机分成假手术组(S组)、缺血再灌注组(IR组)、亚低温组(M组),每组24只;三组缺血10min后分别按再灌注12h、24h、48h,再分为3个亚组,各亚组动物均为8只。大鼠脑缺血再灌注损伤模型制作采用改良四血管阻滞法,免疫组化SP法动态观察各个时间点海马CA1区caspase-3蛋白的变化;光镜和电镜分别观察再灌注48h亚组海马CA1区神经细胞形态和线粒体超微结构的改变。结果(1) 大鼠脑缺血再灌注损伤后12h海马CA1区caspase-3即有明显表达,24h达高峰,48h后仍有较高表达;(2) IR组和M组各时间点caspase-3表达水平比S组明显升高(P<0.05);24h亚组线粒体超微结构和神经细胞形态受损严重;(3) M组各个时间点caspase-3表达水平较IR组明显下降(P<0.05或P<0.01);24h亚组线粒体超微结构和神经元形态均有不同程度的改善。结论 亚低温对caspase-3依赖的线粒体凋亡通路有干预作用,通过维持线粒体膜稳定,抑制释放和激活caspase-3蛋白,保护线粒体的形态功能,从而减少神经细胞凋亡的发生,发挥脑保护作用。     

丙泊酚预处理对大鼠肢体缺血再灌注损伤的影响

目的：观察丙泊酚对大鼠肢体缺血再灌注损伤的影响。方法选择健康成年雄性 SD 大鼠60只,分为假手术组、缺血再灌注组、丙泊酚药物组,每组20只,各组又根据再灌注时间分成4个亚组。复制大鼠经典右下肢缺血再灌注模型,恢复血流灌注前5 min 用丙泊酚注射液（50 mg／kg ,腹腔注射）处理,分别于再灌注后3、6、9、12 h 进行取材,检测血清样本中肿瘤坏死因子-α（TNF-α）、核因子κB（NF-κB）水平、肌肉组织中丙二醛（MDA）、超氧化物歧化酶（SOD）的水平,以及计算肌肉湿干质量比值。结果恢复灌注后各时间段内,相对于缺血再灌注组,丙泊酚处理后能降低 TNF-α、NF-κB 的表达水平（ P ＜0．05）,抑制组织MDA 水平增加（P＜0．05）,抑制 SOD 水平的减少（P＜0．05）,也明显减轻肌肉组织的水肿（P＜0．05）。结论丙泊酚预处理可通过遏制炎症因子表达、减轻氧自由基损害从而对缺血再灌注肢体具有保护作用。     

Effect of different resuscitation strategies on post-resuscitation brain damage in a porcine model of prolonged cardiac arrest

Background The choice of a defibrillation or a cardiopulmonary resuscitation （CPR）-first strategy in the treatment of prolonged cardiac arrest （CA） is still controversial. The purpose of this study was to compare the effects of defibrillation or CPR administered first on neurological prognostic markers in a porcine model of prolonged CA. Methods After 8 minutes of untreated ventricular fibrillation （VF）, 24 inbred Chinese Wuzhishan minipigs were randomized to receive either defibrillation first （ID group, n=12） or chest compression first （IC group, n=12）. In the ID group, a shock was delivered immediately. If defibrillation failed to attain restoration of spontaneous circulation （ROSC）, manual chest compressions were rapidly initiated at a rate of 100 compressions/min and a compression-to-ventilation ratio of 30：2. If VF persisted after five cycles of CPR, a second defibrillation attempt was made. In the IC group, chest compressions were delivered first, followed by a shock. After successful ROSC, hemodynamic status and blood samples were obtained at 0.5, 1, 2, 4, 6, and 24 hours after ROSC. Porcine-specific neuron-specific enolase （NSE） and S100B were measured from sera using enzyme-linked immunosorbent assays. Porcine cerebral performance category scores were used to evaluate preliminary neurological function following 24 hours recovery. Surviving pigs were sacrificed at 24 hours after ROSC and brains were removed for electron microscopy analysis. Results The number of shocks, total defibrillation energy, and time to ROSC were significantly lower in the ID group compared with the IC group. Compared with the IC group, S100B expression was decreased at 2 and 4 hours after ROSC, and NSE expression decreased at 6 and 24 hours after ROSC in the ID group. Brain tissue analysis showed that injury was attenuated in the ID group compared with the IC group. There were no significant differences between 6 and 24 hours survival rates. Conclusion Defibrillation first may result in a shorter tim     

Combined incisional ropivacaine infiltration and pulmonary recruitment manoeuvre for postoperative pain relief after diagnostic hysteroscopy and laparoscopy

Background Preoperative incisional local anaesthesia with ropivacaine is a common method of providing postlaparoscopy pain relief.The pulmonary recruitment manoeuvre also provides pain relief,but the combined effect of these two methods on pain following laparoscopic procedures has not been reported.We investigated the efficacy of combining local anaesthetic infiltration of ropivacaine with pulmonary recruitment manoeuvre on postoperative pain following diagnostic hysteroscopy and laparoscopy.Methods This prospective,randomized,controlled study involved 60 patients divided into two groups （n=30,each）.Group 1 received 20 ml of 0.5％ ropivacaine injected peri-incisionally preoperatively,with intra-abdominal carbon dioxide removed by passive deflation.Group 2 received 20 ml of 0.5％ ropivacaine injected peri-incisionally with five manual inflations of the lungs with a positive-pressure ventilation of 40 cmH2O at the end of surgery.The last inflation was held for 5 seconds.The intensity of postoperative incisional and shoulder pain was evaluated using a numerical rating scale at 0,2,4,8,12,24 and 48 hours postoperatively by an independent blinded anaesthesiologist.Tramadol was given postoperatively for analgesia.Results Compared with group 1,incisional ropivacaine infiltration combined with pulmonary recruitment manoeuvre significantly reduced dynamic pain at 0 hour,4 hours,and 24 hours postoperatively （4.1 ± 2.2 vs.2.1 ± 1.9,P=0.002;2.7 ± 2.7 vs.1.2 ± 1.3,P=0.035; and 3.5 ± 2.1 vs.2.1 ± 1.8,P=0.03,respectively）.Static incisional pain was significantly relieved at 0 hour,2 hours,and 24 hours postoperatively （3.1 ± 1.7 vs.1.6 ± 1.3,P=0.001; 1.4 ± 1.3 vs.0.5 ± 0.8,P=0.012;and 2.3 ± 1.9 vs.1.0 ± 1.5,P=0.038,respectively）.Group 2 had more patients without shoulder pain （P＜0.05） and fewer requiring tramadol （P＜0.05）.Conclusion Ropivacaine with pulmonary recruitment manoeuvre provided simple and effective pain relief after diagnostic hysteroscopy and laparoscopy.     

亚低温对脑缺血再灌注后缺血核心区皮质内IL-1β和MCP-1含量的影响

目的　探讨缺血过程中亚低温对大鼠脑缺血再灌注后缺血核心区皮质内白细胞介素1β(IL 1β)及单核细胞趋化蛋白 (MCP) 1含量的影响。 方法　选用 80只雄性Wistar大鼠 ,随机分为常温组 (37℃ )和亚低温组 (32～ 33℃ ) ,用ELISA法测定缺血 2h再灌不同时间缺血核心区脑皮质内IL 1β和MCP 1含量变化 ;用 2 ,3,5三苯基四氮唑 (TTC)染色法观察脑皮质梗死灶的变化。 结果　常温组再灌注后各时间点缺血核心区皮质内IL 1β含量无明显变化 ;MCP 1含量于再灌注 6h后开始升高 (2 2 5± 8 7)ng/g ,是假手术组的 17 0倍 (P <0 0 5 ) ,4 8h逐渐达到高峰 (110 9± 4 7 0 )ng/g ,是假手术组的 83 7倍 (P <0 0 0 1)。与常温组相比 ,亚低温组再灌注后缺血核心区皮质内IL 1β含量没有明显变化 ,但MCP 1的含量于再灌注后 6h为 (8 7± 7 6 )ng/g(P <0 0 0 5 ) ,再灌注后 4 8h为 (5 6 0± 4 0 3)ng/g(P <0 0 5 ) ,明显低于常温组 ,皮质梗死灶也显著小于常温组。 结论　降低缺血再灌注后脑皮质内MCP 1的含量 ,可能是亚低温发挥脑保护作用的重要途径之一。     

葛根素对脑缺血-再灌注损伤细胞凋亡和p53表达的影响

目的 观察葛根素对预处理后大鼠局灶性脑缺血时海马区凋亡细胞和p53蛋白表达的影响.方法 利用大脑中动脉栓线阻断法制作大鼠局灶性脑缺血2h后再灌注损伤模型.72只SD大鼠随机分为假手术组（S组）、缺血再灌注组（IR组）和葛根素组（P组）.依术后处死动物时间不同,每组分为3个亚组（n=8）.用免疫组化法检测p53蛋白和TUNEL法检测凋亡细胞的表达.结果 P组P2h组p53蛋白表达增高,P24h组显著增高,P72h组p53蛋白表达有所下降,但仍低于IR组（P＜0.01）;P组凋亡细胞数显著低于相应IR组（P＜0.01）.结论 葛根素对大鼠局灶性脑缺血再灌注损伤具有保护作用,其作用机制可能与葛根素抗细胞凋亡、下调p53蛋白有关.     

Hydrogen sulfide defends against the cardiovascular risk of Nw-nitro-L-argininemethyl ester-induced hypertension in rats via the nitric oxide/endothelial nitric oxide synthase pathway

Background Dyslipidemia caused by liver injury is a significant risk factor for cardiovascular complications.Previous studies have shown that hydrogen sulfide （H2S） protects against multiple cardiovascular disease states in a similar manner as nitric oxide （NO）,and NO/endothelial nitric oxide synthase （eNOS） pathway is the key route of NO production.The purpose of this study was to investigate whether H2S can ameliorate the high blood pressure and plasma lipid profile in Nw-nitro-L-argininemethyl ester （L-NAME）-induced hypertensive rats by NO/eNOS pathway.Methods Thirty-six 4-week old Sprague-Dawley （SD） male rats were randomly assigned to 6 groups （n=6）：control group,L-NAME group,control ＋ glibenclamide group,control ＋ NaHS group,L-NAME ＋ NaHS group,and L-NAME ＋ NaHS ＋ glibenclamide group.Measurements were made of plasma triglycerides （TG）,low-density lipoprotein （LDL）,high-density lipoprotein （HDL）,total cholesterol （CHO）,glutamic-pyruvic transaminase （ALT） levels after 5 weeks.Then measurements of NO level and proteins expression of eNOS,P-eNOS,AKT,P-AKT were made in liver tissue.Results After 5 weeks of L-NAME treatment,the blood pressure,plasma TG （（1.22±0.12） mmol/L in L-NAME group vs.（0.68±0.09） mmol/L in control group; P ＜0.05） and LDL （（0.54±0.04） mmol/L in L-NAME group vs.（0.28±0.02） mmol/L in control group; P ＜0.05） concentration were significantly increased,and the plasma HDL （（0.26±0.02） mmol/L in L-NAME group vs.（0.69±0.07） mmol/L in control group; P ＜0.05） concentration significantly decreased.Meanwhile the rats treated with L-NAME exhibit dysfunctional eNOS,diminished NO levels （（1.36±0.09） mmol/g protein in L-NAME group vs.（2.34±0.06） mmol/g protein in control group; P ＜0.05） and pathological changes of the liver.H2S therapy can markedly decrease the blood pressure （（37.25±4.46） mmHg at the fifth week; P ＜0.05）,and ameliorate the plasma TG （（0.59±0.06） mmHg）,     

肢体缺血再灌注后肺组织中NOS的表达

（1）目的 观察肢体缺血再灌注后肺组织中NOS同工酶活性，分布和mRNA表达的变化；（2）方法 复制肢体缺血再灌注模型。实验动物随机分为4组；正常对照组（Control组），损伤组（IR组），L-精氨酸组（L-Arg组）和氨基胍组（AG组），用免疫组织化学方法检测肺组织中NOS蛋白的表达；用RT-PCR方法检测肺组织中NOSmRNA的表达。（3）结果 免疫组织化学结果显示，Control组iNOS染色少有阳性；IR组iNOS染色阳性，染色阳性细胞主要分布在支气管上皮细胞，支气管平滑肌细胞，支气管周围浸润的中性粒细胞也呈阳性表达；AG组iNOS染色较IR组减弱；L-Arg组则无明显差异。eNOS染色在Control组呈阳性，主要分布于毛细血管内皮细胞，其余3组染色均减弱，RT-PCR结果显示，iNOSmRNA的表达在Control组较少，IR组呈高表达，AG组，L-Arg组表达与IR组相比无明显差异；eNOSmRNA表达降低，肺组织中NO的水平增高；给予外源性的L-Arg增加NO的生成，应用AG不影响NOSmRNA的表达，只是 在蛋白水平对iNOS有抑制作用。     

长期远隔后适应对脑缺血再灌注大鼠脑组织神经中丝200表达的影响

目的研究长期远隔缺血后适应对大鼠局灶性脑缺血再灌注损伤后脑组织神经中丝200(NF200)表达的影响。方法应用线栓法制作大鼠大脑中动脉缺血2 h再灌注损伤模型,再灌注即刻给予远端肢体缺血后适应,即双侧股动脉夹闭10 min/放开10 min,反复3次。此后每天给予一次远端肢体缺血后适应。实验分为4组:缺血再灌注7 d组(C7组);缺血再灌注后适应7d组(P7组);缺血再灌注28 d组(C28组);缺血再灌注后适应28 d组(P28组)。每组6只大鼠。采用免疫印迹法研究各组大鼠脑组织中NF200蛋白的表达水平,并采用免疫荧光法观察大鼠脑组织NF200蛋白的表达部位。结果 P7组大鼠脑组织内NF200表达比C7组明显增高(P<0.05),P28组大鼠脑组织内NF200表达比C28组及P7组明显增高(P均<0.05),而C28组大鼠与C7组相比脑组织内NF200表达无明显变化。免疫荧光染色结果显示NF200在神经元胞体及轴突中均有表达。结论长期远隔缺血后适应可增加大鼠脑组织内NF200的表达,可能与减轻脑缺血损伤相关。