钙蛋白酶抑制剂对缺血再灌注损伤脊髓的保护作用

目的 观察大鼠脊髓缺血再灌注损伤后应用钙蛋白酶特异性抑制剂E-64-D,对脊髓神经细胞组织学改变和凋亡的影响及对大鼠后肢运动功能的保护作用.方法 选用纯种雄性成年SD大鼠106只,夹闭右肾动脉分支下腹主动脉30 min,再灌注即刻静脉应用钙蛋白酶特异性抑制剂E-64-D,观察再灌注后3、24、72 h和7 d脊髓损伤节段神经细胞的凋亡及再灌注后24、72h组织病理学改变;对再灌注后72 h的大鼠后肢功能进行评分.结果 脊髓缺血再灌注24 h开始出现神经细胞凋亡现象,脊髓组织出现病理学改变,神经元死亡,胶质细胞增生.应用E-64-D后,凋亡现象和细胞坏死得到抑制,差异有统计学意义(P<0.01).再灌注后72 h后肢功能也得到一定程度的保护.结论 脊髓再灌注损伤后静脉应用E-64-D治疗,可以明显抑制脊髓神经细胞的凋亡,有利于神经元的存活,损伤后3 d大鼠后肢运动功能得到一定程度的改善.     

淫羊藿苷在大鼠脊髓损伤中的神经保护作用

目的:研究淫羊藿苷在大鼠脊髓损伤中的神经保护作用。方法:108只SPF级雄性3月龄SD大鼠按随机数字表法分为实验组、对照组及假手术组3组,每组36只。对照组和实验组采用改良Allen法制作脊髓损伤模型,假手术组仅切开椎板不损伤脊髓。术后即刻实验组给予淫羊藿苷(100 mg/kg)灌胃,对照组和假手术组给予等量生理盐水灌胃,每日2次。术后1、2、3 d采用BBB评分法评定大鼠运动功能;术后72 h采用分光光度法检测髓过氧化物酶(myeloperoxidase,MPO)的活性,酶联免疫吸附测定(ELISA)法检测肿瘤坏死因子(tumor necrosis factor,TNF)-α、白介素(interleukin,IL)-1β的含量,免疫组化染色检测MPO、TNF-α、IL-1β的表达;采用硫代巴比妥酸法检测丙二醛(malondialdehyde,MDA)含量,黄嘌呤氧化酶法检测超氧化物歧化酶(superoxide dismutase,SOD)活性;采用TUNEL法检测细胞凋亡并计算细胞凋亡指数(apoptosis index,AI);光镜观察脊髓损伤后组织病理学的改变并行组织病理学评分。结果:术后各时间点对照组和实验组大鼠BBB评分均显著低于假手术组(P0.05);术后2、3 d实验组大鼠BBB评分均显著高于对照组(P0.05)。术后72 h,对照组和实验组MPO活性和TNF-α、IL-1β的含量显著高于假手术组(P0.05);实验组显著低于对照组(P0.05)。对照组和实验组MPO、TNF-α、IL-1β的表达显著高于假手术组(P0.05);实验组显著低于对照组(P0.05)。对照组和实验组MDA含量显著高于假手术组,实验组显著低于对照组(P0.05);对照组和实验组SOD活性显著低于假手术组,实验组显著高于对照组(P0.05)。对照组和实验组脊髓组织中AI显著高于假手术组,实验组显著低于对照组(P0.05)。对照组和实验组脊髓组织病理学评分均显著高于假手术组,实验组均显著低于对照组(P0.05)。结论:淫羊藿苷能够抑制脊髓损伤后的炎症、脂质过氧化和细胞凋亡,减轻脊髓组织病理学损伤,改善脊髓损伤大鼠的运动功能,有效保护脊髓组织,具有明显的神经保护作用。     

Neuroprotective effects of FK-506, L-carnitine and azathioprine on spinal cord ischemia-reperfusion injury.

OBJECTIVE: In our experimental study, we aimed to test the effect of FK506, azathioprine and L-carnitine on protection of spinal cord injury due to ischemia-reperfusion. METHODS: Twenty-seven Sprague-Dawley male rats were randomly divided into five groups. They were subjected to spinal cord ischemia by clamping the abdominal aorta for 45 min. Thirty minutes before the aortic clamping, group I received 0.5 mg/kg FK506, group II received 100 mg/kg L-carnitine, group III received 4 mg/kg azathioprine, the fourth group was the control group and received only normal saline injection intravenously and the last group was the sham group. Neurological status was scored by using the Tarlov scoring system. Sections of the lumbar cord were harvested for histopathological grades (1-4), having regard to percentage of the apoptotic cells. RESULTS: Hind-limb motor function had recovered normally 48 h after the operation in all rats which received FK506, azathioprine and L-carnitine prophylactically. In contrast, all rats in the control group had deteriorated to paraplegia by 48 h after the operation (P<0.05). Histopathologic sections in the involved spinal cord segment showed that a greater number of motor neuron cells were preserved and there were less apoptotic cells in the rats that received FK506, azathioprine and L-carnitine than those in control group. CONCLUSIONS: These results suggest that prophylactic use of FK506, azathioprine and L-carnitine protects motor neuron cells from ischemic spinal cord injury.     

Neuroprotective effect of regional carnitine on spinal cord ischemia--reperfusion injury.

OBJECTIVE: The purpose of this study was to investigate the effect of regional infusion of carnitine on spinal cord ischemia--reperfusion (I--R) in rabbits. METHODS: The 36 rabbits were divided into four equal groups, group I (sham operated, no I--R injury), group II (control, only I--R), group III (I--R+intraaortic lactated Ringer's, LR, during aortic occlusion), group IV (I--R+LR plus 100mg/kg carnitine). Spinal cord ischemia was induced by clamping the aorta both below the left renal artery and above the aortic bifurcation. The spinal cord function of all animals was assessed clinically 24h after aortic declamping. Spinal cord samples were taken to measure the levels of tissue malondialdehyde (MDA) and to evaluate the histopathological changes. RESULTS: We found significant increases in the levels of MDA in groups II and III compared with group I (P<0.01), and elevation of MDA in group IV was insignificant. In group II, all animals (100%) were paraplegic with Tarlov's score of 0 and in group III, eight animals (88%) were paraplegic with Tarlov's score of 0 or 1. None of the animals (0%) from group IV was paraplegic. Histologic examination of spinal cords from group IV animals revealed that the appearance of the spinal cord was relatively preserved, whereas spinal cords from groups II and III had evidence of acute neuronal injury. CONCLUSION: The results suggest that regional infusion of carnitine during aortic clamping reduces spinal cord injury and prevents neurologic damage in rabbit spinal cord I--R model.     

Levosimendan effect on spinal cord ischemia-reperfusion injury following aortic clamping

BACKGROUND AND AIM OF THE STUDY: The new calcium sensitizer, levosimendan, not only acts as a positive inotropic agent but also, vasodilates both venules and arterioles. The aim of this experimental study was to investigate whether levosimendan has protective effects on spinal cord ischemia-reperfusion injury. MATERIAL AND METHODS: Twelve New Zealand rabbits were enrolled in this study. In addition to the control group, levosimendan is administered to the experimental group with a loading dose of 12 microg/kg prior to ischemia over a 10-minute period, followed by an infusion of 0.2 microg/kg/min during the ischemia period (30-minutes). Following the neurologic evaluation at the 24th hour of reperfusion, lumbar spinal cords were removed in order to perform microscopic examination and malondialdehyde (MDA) and myeloperoxidase (MPO) measurements. RESULTS: The mean Tarlov score of the levosimendan group (3.25) was higher than the control group (0.7) (p< 0.05). MDA level was found significantly lower in the levosimendan group when compared with the control group as 1.6 +/- 0.4 nmol/gr and 189.3 +/- 43.6 nmol/gr respectively (p < 0.05). MPO level was also found statistically significant when we compared levosimendan group with the control group. It was calculated as 11.3 +/- 1.0 micro/gr tissue and 39.1 +/- 16.9 micro/gr in the levosimendan and the control groups (p< 0.05). Light microscopic examination was carried out with tissue samples in the 24th hour of the reperfusion. Levosimendan group had better preservation with the microscopic appearance with respect to the control group. CONCLUSION: Levosimendan exhibits an important protection by means of neurological outcome, histopathological, and biochemical analysis for the ischemia-reperfusion injury of the spinal cord following the aortic clamping.     

Neuroprotective assessment of prolonged local hypothermia post contusive spinal cord injury in rodent model

Background Context

Although general hypothermia is recognized as a clinically applicable neuroprotective intervention, acute moderate local hypothermia post contusive spinal cord injury (SCI) is being considered a more effective approach. Previously, we have investigated the feasibility and safety of inducing prolonged local hypothermia in the central nervous system of a rodent model.

缺血后处理对兔脊髓缺血-再灌注损伤的保护作用

目的研究缺血后处理是否可以减轻兔脊髓缺血再灌注的损伤。方法雄性新西兰大白兔30只,随机分为五组,每组6只。假手术组(N1组)仅行单纯手术操作但不阻闭腹主动脉;对照组(N2组)行单纯缺血再灌注;缺血后处理15s/30s/60s(PA/PB/PC组)分别于阻闭腹主动脉15min后,再灌注15s/30s/60s,缺血15s/30s/60s,反复3次。再灌注48h时对所有动物的后肢运动功能进行评分并行脊髓前角正常神经元计数。结果PB组再灌注48h后肢运动功能评分[3.5(2～4)分],明显高于N2组[2(1～3)分](P<0.05),其他各组与N2组相比差异无显著意义。脊髓前角正常神经元计数PB组为36.7±7.0,明显多于N2组25.7±4.3(P<0.01),而PA组18.2±2.2和PC组8.0±4.1则明显少于N2组(P<0.05)。结论缺血后处理对兔脊髓缺血再灌注损伤的作用取决于后处理时间,缺血后处理30s/30s对脊髓缺血再灌注损伤具有保护作用,而缺血后处理15s/15s和60s/60s会加重脊髓损伤。     

阿魏酸对家兔脊髓缺血再灌注损伤的防治作用

目的　研究阿魏酸对家兔肾下主动脉阻断所致脊髓损害的防治作用及其机理。方法家兔 2 4只 ,随机分为假手术组 (A组 ) ,缺血再灌注损伤组 (B组 )及阿魏酸组 (C组 ) ,每组 8只。B、C组肾下主动脉阻断 4 0分钟后开放 ,再灌注 7天。C组于阻断前 15分钟一次性静注阿魏酸 5 0mg/kg ,余两组则以同样方法静注等容量生理盐水作对照。测定阻断前 (C0 )、开放前 (C40 )、开放后 6 0分钟(R60 )及 7天 (R7d)血清中MDA、SOD、S10 0蛋白、TNFα、IL 1β的含量 ;术后观察后肢神经功能和脊髓形态学变化。结果　 (1)B组缺血及再灌注后血清MDA、S10 0蛋白、TNFα、IL 1β含量明显高于C0点及A组值 (P <0 0 1) ;C组明显低于B组 (P <0 0 1) ,与A组无显著性差异。 (2 )B组缺血及再灌注后SOD活力明显低于C0 点及A组值 (P <0 0 1) ;C组明显高于B组 (P <0 0 1) ,与A组无显著性差异。 (3)C组瘫痪发生率明显低于B组 (P <0 0 1) ,其后肢神经功能评分显著高于B组 (P <0 0 1)。 (4)B组脊髓病理变化较重 ,可见大量神经元坏死 ;C组偶有神经元坏死。结论　预防性静注阿魏酸对家兔主动脉阻断所致脊髓损害有良好的防治作用。其机理与阿魏酸抗氧化、抗炎及抑制TNFα、IL 1β水平升高有关     

芦荟多糖对脊髓缺血损伤的神经保护作用

目的:探讨芦荟多糖(aloe polysaccharide,AP)对兔脊髓缺血损伤是否有神经保护作用.方法:32只成年雄性新西兰兔随机分成4组(每组8只 ),即对照组(C 组)、芦荟多糖组(A组)、溶剂对照组( V组 ) 及假手术组(S组).A组在脊髓缺血前30min经耳缘静脉给予50m·kg-1芦荟多糖;V组以同样方式给予等容量生理盐水;C组仅仅制备脊髓缺血损伤模型,不进行其它处理;S组仅仅暴露腹主动脉,而不阻断它,其他处理同C组;兔脊髓缺血模型采用夹闭兔腹主动脉肾下段20min.再灌注后48h,对所有动物神经功能评分,然后处死动物取脊髓(L5-7),制作标本行组织病理学观察.结果:A组的神经功能评分和脊髓前角正常神经细胞数明显多于C组及V组(P<0.01);C组及V组的神经功能评分和脊髓前角正常神经细胞数组间无明显差异(P>0.05);神经功能评分与其对应脊髓前角正常神经细胞计数之间有显著相关性(r=0.804,P<0.01).结论:芦荟多糖对兔脊髓缺血再灌注损伤有明显的神经保护作用.     

The effect of hypothermia on sensory-motor function and tissue sparing after spinal cord injury

Background contextIn recent years, hypothermia has been described as a therapeutic approach that leads to potential protective effects via minimization of secondary damage consequences, reduction of neurologic deficit, and increase of motor performance after spinal cord injury (SCI) in animal models and humans.PurposeThe objective of this study was to determine the therapeutic efficacy of hypothermia treatment on sensory-motor function and bladder activity outcome correlated with the white and gray matter sparing and neuronal survival after SCI in adult rats.Study designA standardized animal model of compression SCI was used to test the hypothesis that hypothermia could have a neuroprotective effect on neural cell death and loss of white and/or gray matter.MethodsAnimals underwent spinal cord compression injury at the Th8–Th9 level followed by systemic hypothermia of 32.0°C with gradual re-warming to 37.0°C. Motor function of hind limbs (BBB score) and mechanical allodynia (von Frey hair filaments) together with function of urinary bladder was monitored in all experimental animals throughout the whole survival period.ResultsPresent results showed that hypothermia had beneficial effects on urinary bladder activity and on locomotor function recovery at Days 7 and 14 post-injury. Furthermore, significant increase of NeuN-positive neuron survival within dorsal and ventral horns at Days 7, 14, and 21 were documented.ConclusionsOur conclusions suggest that hypothermia treatment may not only promote survival of neurons, which can have a significant impact on the improvement of motor and vegetative functions, but also induce mechanical allodynia.     

三甲氧苄嗪对大鼠脊髓缺血-再灌注损伤的保护作用

目的评价三甲氧苄嗪(trimetazidine)对大鼠脊髓缺血-再灌注损伤的保护作用,并探讨其作用机制. 方法 45只SD大鼠采用随机数字表法分为3组,每组15只.建立大鼠脊髓缺血损伤模型,假手术组:行开腹手术,不阻断主动脉;对照组:剖腹后阻断主动脉20分钟;三甲氧苄嗪组:于主动脉阻断前10分钟静脉内注射三甲氧苄嗪(3mg/kg),其余处理与对照组相同.测定血浆丙二醛(MDA)含量,术后48小时按Tarlov评分标准评价动物后肢神经功能,取脊髓进行含水量、MDA含量测定及组织病理学检查.结果三甲氧苄嗪组血浆MDA含量明显低于对照组(P<0.05),动物后肢神经功能评分明显优于对照组(P<0.01),脊髓含水量、MDA含量明显低于对照组(P<0.01);三甲氧苄嗪组在光学显微镜下脊髓病理改变轻微,而对照组脊髓损伤较重,两组病理评分差别有显著性意义(P<0.01).结论三甲氧苄嗪对大鼠脊髓缺血-再灌注损伤具有明显的保护作用.     

硫酸镁对兔脊髓缺血再灌注损伤保护作用的研究

目的:探讨硫酸镁对兔脊髓缺血再灌注损伤的保护效果。方法:27只新西兰大白兔,随机分为A组(硫酸镁处理组)、B组(生理盐水)和C组(假手术对照组)。A、B两组参照Tetik方法建立兔脊髓腰骶段缺血模型,比较三组动物不同时间点的体感诱发电位(SEP)、后肢运动功能评分及缺血再灌注后48h的病理学改变。结果:C组SEP没有明显变化,动物均完全康复。缺血30min时B组波形消失,A组波幅降为基线的(29.3±1.9)%。再灌注60min后A组、B组SEP波幅分别渐升致基线的(74.5±2.3)%和(49.2±2.1)%。A组N1、P1波峰潜伏期在缺血30min及再灌注60min时均明显优于B组(P<0.05);再灌注24h和48h后,A组的后肢运动功能评分均显著高于B组(P<0.05);再灌注48h后A组的脊髓前角神经细胞计数显著高于B组(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。     

胞液型磷脂酶A2抑制剂上调自噬通量改善脊髓损伤后神经功能的作用及机制研究

目的:探讨胞液型磷脂酶A2(cytosolic phospholipase A 2,cPLA2)抑制剂改善脊髓损伤(spinal cord injury,SCI)后神经功能的机制。方法:36只雌性SD大鼠,体质量(280±20) g,3月龄,分为3组(n=12):假模型组、SCI组、SCI+花生四烯酸三氟甲基酮(arachidonyl trifluoromethyl ketone,AACOCF3)组。3组均建立球囊压迫SCI模型。假模型组置入球囊后不做加压处理,余两组球囊加压持续48 h造脊髓压迫模型。造模成功后,对SCI+AACOCF3组大鼠腹腔注射cPLA2的特异性抑制剂AACOCF3。余两组大鼠腹腔注射生理盐水。分别于造模后7、14 d分批处死动物,于受损脊髓组织取材,行组织形态学观察,检测cPLA2和多种自噬通量相关分子的表达,测试运动功能的恢复情况。结果:脊髓组织形态检测显示:假模型组脊髓组织结构完整,神经元和胶质细胞数量和形态正常。在SCI组可见脊髓组织断裂,有大而突出的脊髓空洞。在SCI+AACOCF3组,脊髓组织比SCI组更完整,可见脊髓空洞融合,有更多存活的神经元,胶...     

高氧液预处理对兔脊髓缺血-再灌注损伤的保护作用

目的　探讨高氧液预处理对兔脊髓缺血 再灌注损伤的作用。方法　 2 0只成年雄性新西兰大白兔随机分成对照组 (n =1 0 )及预处理组 (n =1 0 )。预处理组每天静脉给予 1 0ml/kg高氧液 ,2 0分钟匀速泵完 ,连续 5天 ;对照组用同样方法给予等容量生理盐水。最后一次预处理结束后2 4小时 ,夹闭腹主动脉肾下段 2 0分钟 ,制作兔脊髓缺血模型 ;再灌注后 4、8、1 2、2 4和 48小时分别对动物神经功能评分 ;再灌注 48小时后 ,处死动物取脊髓 (L5～ 7) ,制作标本行组织病理学观察。结果　预处理组神经功能评分在各时间点均明显高于对照组 (P <0 0 5) ;与对照组相比 ,预处理组脊髓前角正常神经细胞数明显增多 (P <0 0 5) ,而且神经功能评分与其对应脊髓前角正常神经细胞计数之间有显著相关性 (r=0 894,P <0 0 1 )。结论　高氧液预处理对兔脊髓缺血 再灌注损伤有显著的保护作用。     

氢饱和生理盐水对兔脊髓缺血再灌注损伤的神经保护作用

目的 研究氢气对脊髓缺血再灌注损伤的保护作用及其潜在机制。方法 新西兰兔随机分为3组：对照组、脊髓缺血再灌注损伤组和氢水治疗组。对照组仅接受暴露,无脊髓缺血再灌注损伤;缺血再灌注组动物采用ZIVIN法建立脊髓缺血再灌注损伤模型,造成脊髓腰骶段缺血35 min 后行再灌注;氢水治疗组动物在再灌注前5 min腹腔注射饱和氢盐水（5 mL/kg）,再灌注后8 h重复注射。不同时间点检测后肢运动功能。术后72 h取脊髓进行HE染色、TUNEL染色、氧化-抗氧化指标检测及ELISA检测细胞因子。结果 含氢生理盐水治疗能显著改善动物神经功能、抑制脊髓神经元凋亡、抑制氧化应激、改善抗氧化能力,同时降低炎症相关细胞因子,从而发挥脊髓保护作用。结论 腹腔注射含氢生理盐水通过抗氧化和抗炎对脊髓缺血再灌注损伤发挥保护作用。     

预防使用大剂量甲基强的松龙对大鼠急性脊髓损伤的神经保护作用

目的研究预防使用大剂量甲基强的松龙对急性脊髓损伤大鼠的神经功能保护作用方法采用Allen重物打击模型，动物随机分为三组：对照组；脊髓损伤组；预防使用大剂量甲基强的松龙组。分别在脊髓损伤后24h、72h进行神经功能评分(Tarlov评分障碍率、Molt斜板功能障碍率)、脊髓病理形态学及超微结构观察、神经中丝(NF)及胶质纤维酸性蛋白(GFAP)观察、结果预防使用大剂量MP可明显改善损伤脊髓的病理形态及超微结构；脊髓损伤后72h大鼠神经功能评分明显提高；显著提高NF的表达、抑制GFAP的表达．结论预防使用大剂量甲基强的松龙对大鼠急性脊髓损伤有神经保护作用