Upgraded Nerve Growth Factor Expression Induced by Low-Intensity Continuous-Wave Ultrasound Accelerates Regeneration of Neurotometicly Injured Sciatic Nerve in Rats

Low-intensity ultrasound (LIU) can stimulate injured nerve regeneration but the mechanism is still unclear. We investigated the stimulating effect and its mechanism of continuous-wave LIU on neurotometic injury of sciatic nerve. The right sciatic nerves of 64 adult Wistar rats were first crushed and then exposed (32 rats) or sham-exposed (32 rats) to LIU at the crush site. The LIU had a spatial averaged and temporal averaged intensity of 0.25W/cm² operated at 1.0 MHz for 1 min every other day. At various stages (the second, fourth, sixth and eighth weeks) after LIU exposure, the sciatic nerve function index (SFI), the sensory nerve conduction velocity (SNCV), the expression of nerve growth factor (NGF) and sample histology were studied. It was found that the density of nerve fibers with myelin sheath, SFI, SNCV and NGF expression of the treatment group were higher than that of control group (p < 0.05). It has been determined that LIU treatment can accelerate the regeneration and functional recovery of neurotometic injured sciatic nerve at earlier stages after injury, the upgraded expression of NGF induced by LIU may be the primary mechanism of the acceleration effects. (E-mail: wangzhibiao@haifu.com.cn)     

神经胶质生长因子促进受损周围神经功能恢复

目的评价了重组体人类神经胶质生长因子Ⅱ(rhGGF2)对大鼠坐骨神经挤压伤后运动功能恢复的效果.方法73只大白鼠被分为3组.一组(n=5)实施模拟挤压操作.在二组(n=34)、三组(n=34)中,每只动物选一5mm长的坐骨神经段承受100g挤压2h.其中,三组用rhGGF2治疗(1mg/kg挤压后皮下注射,1次/d,连续4d),二组用相同量的载体治疗.通过计算坐骨神经功能指数(SFI)和测量趾长伸肌(EDL)强直收缩力来评价神经运动功能恢复.结果与二组相比,三组神经在术后11～21d表现出显著的SFI改善.三组肌肉收缩力强于二组,并从4～14d在70Hz和100Hz刺激下有显著性差异.组织学切片显示三组呈现较轻的轴突溃变和较早的神经再生.结论用rhGGF2治疗坐骨神经挤压伤能有效的促进神经再生,进而显著改善其功能的恢复.     

The Effect of Low-Intensity Ultrasound on Brain-Derived Neurotropic Factor Expression in a Rat Sciatic Nerve Crushed Injury Model

Low-intensity ultrasound (LIU) can improve nerve regeneration and functional recovery after peripheral nerve crush injury, but the underlying mechanism is not clear. The objective of this study was to examine the effects of LIU on rat sciatic crush injury and to investigate a possible molecular mechanism. Adult male Sprague-Dawley rats underwent left sciatic nerve crush surgery and were then randomized into two groups: a treatment group that received LIU every other d, and a control group that received sham exposure. Compared with rats in the control group, rats in the treatment group had higher sciatic nerve function indexes, compound muscle action potentials, wet weight ratios of the target muscle and mRNA expression of brain-derived neurotropic factor (BDNF) in the crushed nerve and ipsilateral dorsal root ganglia. Our findings suggest that LIU might promote injured nerve regeneration by stimulating BDNF release.     

低强度超声促进周围神经损伤后的再生

目的：探讨低强度超声对周围神经损伤后再生的作用。方法：将64只大鼠右侧坐骨神经重度钳夹伤制作神经损伤模型，随机分为2组各32只。超声组造模侧神经损伤处以声强250mW／cm^2、频率1．0MHz的超声进行体外治疗，隔天1次；对照组相应部位予以未启动治疗系统的假治疗。术后不同时期进行电生理、坐骨神经功能指数等指标测定及组织学检查。结果：超声组损伤神经远侧Wallerian变性进程加速、雪旺细胞增殖、变性组织吸收，轴索及髓鞘再生、感觉传导速度及坐骨神经功能的恢复等与对照组比较均提前（P〈0．01或P〈0．05）。结论：低强度超声通过影响神经再生的多个环节而促进周围神经的再生和功能恢复。     

运动疗法促进坐骨神经损伤小鼠的运动功能恢复

目的:评估运动疗法对坐骨神经损伤小鼠运动功能恢复的促进作用。方法:将60只雄性C57BL/6小鼠随机分为假手术组、坐骨神经损伤组和运动治疗组,每组20只。通过挤压坐骨神经建立坐骨神经损伤小鼠模型。对各组小鼠脚趾形态和坐骨神经功能指数(Sciatic Functional Index,SFI)进行评估。通过免疫荧光染色观察各组小鼠神经纤维的形态及数量。使用透射电子显微镜检查小鼠坐骨神经损伤部位远端的有髓神经纤维数量。使用real-time PCR检测与神经损伤修复相关的基因。结果:与假手术组比较,坐骨神经损伤组小鼠脚趾不能张开,SFI高且下降速度慢,差异有统计学意义(P<0.001)。与坐骨神经损伤组比较,运动治疗组小鼠脚趾张开功能轻度恢复,SFI下降速度快,差异有统计学意义(P<0.001)。免疫荧光染色结果显示:坐骨神经损伤组受损部位远端神经纤维数量少,密度低;而运动治疗组受损部位远端神经纤维数量和密度均升高。电镜结果显示:与假手术组比较,坐骨神经损伤组小鼠受损部位远端有髓神经纤维比例降低,差异有统计学意义(P<0.001);与坐骨神经损伤组比较,运动治疗组小鼠受损部位远端有髓神经纤维比例升高,差异有统计学意义(P<0.01)。Real-time PCR结果显示:与假手术组比较,坐骨神经损伤组BDNF,Mpz和Cdh1基因表达均降低(P<0.01或P<0.001),Artn基因表达升高(P<0.001);与坐骨神经损伤组比较,运动治疗组BDNF,Mpz,Cdh1,Gap-43,cJun基因表达水平升高(P<0.01或P<0.001),Artn基因表达降低(P<0.01)。结论:运动疗法对坐骨神经损伤小鼠的运动功能恢复有促进作用。     

不同频率的脉冲电磁场对大鼠坐骨神经损伤的疗效

目的:采用不同频率脉冲电磁场(PEMF)干预坐骨神经损伤大鼠,探索PEMF治疗坐骨神经损伤的最适治疗频率.方法:SD大鼠50只,随机分为假手术组、对照组、2 Hz组、10 Hz组和40 Hz组,每组10只,除假手术组外,所有大鼠按文献方法钳夹坐骨神经造模.2 Hz组、10 Hz组和40 Hz组在强度为0.3 mT,频率...     

神经生长因子对挤压伤坐骨神经再生的促进作用

背景神经生长因子(nerve growth factor,NGF)不仅是维持促进中枢神经系统发育、分化、存活的基本的生长因子,而且在外周神经损伤的修复中也起着重要的作用.目的观察NGF肌注对大鼠坐骨神经挤压伤后神经再生恢复以及功能的影响.设计以实验动物为研究对象,随机对照的重复观察测量,探索性研究.单位一所军医大学的新药评价中心.材料实验于1999-07/2000-03在第二军医大学基础部新药评价中心完成.SD大鼠40只,雌雄各半,体质量200～250 g,上海西普尔-必凯实验动物有限公司提供.方法将40只大鼠随机分成NGF高、中、低剂量组,正常对照和模型对照组.距坐骨切迹远端6 mm处钳夹坐骨神经,使产生-4 mm宽的挤压伤.NGF高、中、低剂量组分别给予NGF 8,4和2μg/kg(1.6×103,8×102和4×102 IU/kg)药物,肌注1次/d,连续56 d.主要观察指标①手术后的不同时间神经传导速度(nerve conduction ve1ocities,NCV)和坐骨神经功能指数(sciatic functional index,SFI).②组织形态学评价.结果与模型对照组相比,高剂量组在35,56 d,中剂量组在35 d的NCV均显著加快(t=2.32～5.14,P＜0.05～0.01);高、中、低3个剂量组在手术14 d后的SFI与模型组相比,差异均有显著性意义(t=2.29～6.28,P＜0.05～0.01),且高剂量组恢复较明显,至56 d各剂量组SFI各组差异均无显著性意义;组织形态学显示,NGF治疗组神经髓鞘、轴索与正常对照组相比,差异无显著性意义;而模型组髓鞘出现脱失,细微结构不清晰,许旺细胞变性坏死.结论NGF对大鼠坐骨神经受损部位的神经髓鞘及轴索有明显的改善作用,能促进其神经纤维的再生及神经功能的恢复.     

神经生长因子和碱性成纤维细胞生长因子联用治疗坐骨神经损伤实验研究

INTRODUCTIONNowdays,manynervenutrientfactorswerefoundtohaverepaireffectonnerveinjury犤1.However,manyexperimentshaveconcen-tratedontheeffectofsinglefactor.Ourresearchwerefocusedoncombinationeffectofnervegrowthfactor(NGF)andbasicfibrob-lastgrowthfactor(bFGF)onsciaticnerveinjuryandprovidecluestoclinicaltreatment.MATERIALSANDMETHODSMaterialsExperimentanimalsandgroupdivision96femaleWistarrats,weighting220-240gwererandomlydividedintonormalsalinegroup,NGFgroup,bFGFgroupandNGF+bFGF…     

雷公藤甲素在羊膜复合异体神经移植治疗坐骨神经损伤中的应用

目的：探讨雷公藤甲素对羊膜复合异体神经移植促神经再生和功能恢复的作用。方法：成年SD雄性大鼠30只,随机分3组,切除10mm坐骨神经造模,造模后3组分别采用自体神经移植、异体神经移植加雷公藤药物、异体神经移植。移植术后第24周,观察移植段神经形态学、坐骨神经指数（SFI,术后第8周开始）、胫前肌湿重、单位面积移植神经中段轴突数量和髓鞘厚度。结果：移植术后第24周自体神经移植组和异体神经移植加雷公藤药物组的坐骨神经指数、单位面积移植神经中段轴突数量和髓鞘厚度、胫前肌湿重各项检测指标无显著差异（P>0.05）, 但再生神经形态和功能恢复良好,检测的各项指标明显优于异体神经移植组（P<0.05）。结论：雷公藤甲素可促进同种异体神经移植神经再生和功能恢复治疗坐骨神经损伤。     

毫米波对周围神经损伤修复的影响

目的探讨毫米波对周围神经损伤修复的影响。方法将36只SD雄性大白鼠制作成左侧坐骨神经钳夹伤模型，随机分为治疗组和对照组。治疗组在神经损伤24h后，用毫米波辐射损伤部位，每周5次，每次30min，从运动功能、电生理、组织学等方面观察其对大鼠坐骨神经损伤修复的影响。结果治疗组在术后2，4，6周的运动神经传导速度均显著高于对照组；运动功能恢复时间明显短于对照组；电镜观察显示，对照组在术后2周的神经变性程度比治疗组严重，治疗组在术后4周和6周的神经再生数目和成熟度均优于对照组。结论毫米波能够促进周围神经损伤的修复和功能恢复。     

兔坐骨神经急性挤压伤MRI定量研究

目的探讨兔坐骨神经急性挤压伤MRI神经/肌肉信号比(SIR)在诊断外周神经损伤中的价值.方法32只新西兰白兔按钳夹力的不同随机分为A、B两组,建立兔坐骨神经急性挤压伤模型,于损伤后1、2、4、8周分别行双侧坐骨神经MR扫描,测量双侧坐骨神经各序列SIR值.结果神经挤压伤后,除T1WI上无明显改变,在其余四序列上SIR均不同程度升高,1周时神经远段SIR升高,2周时SIR达高峰,4周时开始下降,8周时下降较明显,与损伤后神经退变和再生及肢体功能的动态变化相一致.损伤侧神经远段SIR明显高于对照侧(P＜0.001).结论SIR动态测量可直观、客观、无创性反映神经退变和再生的过程,为临床判断预后提供客观依据.     

联合应用NGF、CNTF和GDNF对大鼠坐骨神经结构和功能恢复的影响

目的：探讨联合应用NGF、CNTF和GDNF对大鼠坐骨神经结构和功能恢复的影响。方法：采用大鼠坐骨神经离断模型，实验动物按NGF、CNTF、GDNF单独使用，两两组合使用，三种因子同时应用以及对照组共分为8组。测量各组坐骨神经功能指数、神经电生理参数、腓肠肌湿重恢复率、再生神经纤维形态参数。结果：三种因子联合治疗组坐骨神经功能指数、神经传导速度、动作电位波幅、腓肠肌湿重恢复最佳；除髓鞘厚度略小于NGF和CNTF联合治疗组外．神经纤维直径、再生轴突数量及神经组织面积均大于其他各组。结论：联合应用NGF、CNTF和GDNF对再生神经结构和功能恢复的作用优于其中一种因子单独使用或两种因子联合应用。     

复原再生汤对大鼠周围神经损伤后修复的作用

目的:观察复原再生汤对大鼠周围神经损伤的再生作用。方法:Wistar大鼠60只,采用钳夹左侧坐骨神经建立周围神经损伤模型,随机分为3组各20只,分别用复原再生汤(F组)、甲钴胺加VitB1(M组)及生理盐水(K组)灌胃。给药4周后进行坐骨神经功能指数(SFI)、神经电生理学、肌肉及神经组织形态学的检测。结果:给药4周后,F组大鼠SFI指数、神经传导速度及复合肌肉诱发电位振幅及小腿三头肌湿重、肌细胞截面积、有髓神经轴突计数等恢复率均显著优于M组及K组,M组优于K组(均P0.05)。结论:复原再生汤可促进大鼠周围神经损伤早期的修复、再生和功能的恢复。     

生物粘接端端缝合法修复外周神经的实验研究

目的　研究生物粘接端端缝合修复外周神经的早期效果。方法　选用 Wister大鼠 32只 ,在双目放大镜下分别用生物粘接端端缝合法和单纯端端缝合法修复坐骨神经损伤 ,2周后进行组织形态学、电生理学、坐骨神经功能指数检测评定。结果　生物粘接端缝合组各项指标均优于对照组 ,其神经纤维的生长速度、数量明显优于单纯缝合组 ,SFI的恢复优于单纯缝合组。结论　生物粘接端端缝合法可以促进神经再生 ,加快神经再生速度与神经功能恢复。     

“三法三穴”推拿手法对坐骨神经损伤大鼠运动功能和转化生长因子β1/Smad2通路蛋白表达的影响

目的 探讨“三法三穴”推拿手法对坐骨神经损伤大鼠后肢运动功能,施万细胞增殖、髓鞘修复以及坐骨神经中转化生长因子β1 (TGF-β1)/Smad2通路蛋白表达的影响。方法 66只雄性Sprague-Dawley大鼠随机分为假手术组(n = 22)、模型组(n = 22)和观察组(n = 22)。模型组和观察组采用夹持法制备坐骨神经损伤模型。造模后第8天,观察组每天以点法、拨法、揉法定性定量刺激大鼠术侧殷门、承山、阳陵泉。分别于干预前和干预21 d测量坐骨神经功能指数(SFI);干预前,干预7 d、14 d、21 d行斜板测试;干预21 d,免疫荧光染色观察S100、TGF-β1、Smad2的表达;干预前,干预7 d、21 d,Western blotting检测TGF-β1、Smad2和p-Smad2蛋白表达。结果 干预前,模型组和观察组SFI和斜板测试角度低于假手术组(P < 0.05);干预21 d,观察组SFI和斜板测试角度均高于模型组( P< 0.05)。免疫荧光染色显示,干预21 d,模型组坐骨神经S100表达明显低于假手术组(P < 0.01),观察组高于模型组( P < 0.05),且与假手术组比较无显著性差异( P > 0.05)。Western blotting显示,干预前和干预7 d,模型组TGF-β1、Smad2和p-Smad2表达较假手术组升高( P < 0.05);干预21 d,三组间各蛋白表达均无显著性差异( P > 0.05)。 结论 “三法三穴”推拿手法能促进施万细胞增殖,促进髓鞘恢复,改善坐骨神经损伤大鼠后肢运动功能,但该作用可能与TGF-β1/Smad2通路无关。     

Effect of Extracorporeal Shock Wave Therapy on Denervation Atrophy and Function Caused by Sciatic Nerve Injury

[Purpose] The present study examined the effects of treatment using extracorporeal shock wave therapy (ESWT) on the muscle weight and function of the hind limb in sciatic nerve injury. [Subjects] Forty rats with sciatic nerve crushing injury were randomly divided into two groups: an ESWT group (n=20), and a control group (n=20). [Methods] The ESWT group received extracorporeal shock wave treatment, and the control group did not receive any treatment after injury. Experimental animals were measured for muscle weight on an electronic scale and were tested for function on a sciatic functional index (SFI). [Results] All groups showed significant increases in the weights of the left soleus and gastrocnemius muscles, and decreases in the weights of the right soleus and gastrocnemius muscles (p<0.05). Comparison of SFI scores and muscle weights between the groups showed significant differences in SFI scores, and the right soleus and gastrocnemius muscles (p<0.05) [Conclusion] Exercise programs that use ESWT can be said to be effective at improving the function of the sciatic nerve and preventing the denervation atrophy.Key words: ESWT, Sciatic nerve, Peripheral nerve     

Low-Intensity Pulsed Ultrasound Prompts Both Functional and Histologic Improvements While Upregulating the Brain-Derived Neurotrophic Factor Expression after Sciatic Crush Injury in Rats

The aim of this study was to determine that low-intensity pulsed ultrasound (LIPUS) at an intensity of 140 mW/cm² promotes functional and histologic improvements in sciatic nerve crush injury in a rat model and to investigate changes over time in relevant growth factors and receptors, exploring the mechanism of LIPUS in the recovery process after injury. Toe angle in the toe-off phase, regenerative axonal length, myelinated nerve fiber density, diameter of myelinated nerve fiber, axon diameter and myelin sheath thickness were significantly higher in the LIPUS group than in the sham group. Gene and protein expression of brain-derived neurotrophic factor (BDNF) was upregulated in the LIPUS group. In conclusion, LIPUS contributed to rapid functional and histologic improvement and upregulated BDNF expression after sciatic nerve crush injury in rats.     

微囊化转染神经生长因子基因细胞移植在周围神经再生中的作用

目的探讨应用免疫隔离技术进行转染神经生长因子（NGF）基因的3T3细胞移植促进周围神经损伤后再生的可行性.方法采用海藻酸钠-聚赖氨酸-海藻酸钠（APA）微胶囊包埋NGF-3T3细胞并进行培养;制备坐骨神经横断损伤SD大鼠模型,96只SD大鼠随机分A组（微囊化NGF-3T3细胞组）、B组（空胶囊组）、C组（转染NGF的3T3细胞组）和D组（阴性对照组）.分别采用神经干动作电位（NAP）、神经传导速度（NCV）和坐骨神经功能指数（SFI）检测坐骨神经功能恢复情况.结果微囊化NGF-3T3细胞培养后保持活性和增殖能力,将具有分化潜能的大鼠嗜铬细胞瘤细胞与其共培养,7 d时细胞胞体分化成多边形或锥形,形成突起;培养10 d左右NGF分泌量最高,达269 pg/ml;培育50 d仍然保持在208 pg/ml.移植术后4、8及12周时,A组大鼠的NAP及NCV均大于B、C、D组（P＜0.05）,而B、C、D三组之间无显著性差异（P＞0.05）;A组大鼠的SFI恢复情况优于B、C、D组（P＜0.05）,而B、C、D三组之间无显著性差异（P＞0.05）.结论微囊化NGF-3T3细胞在体外培养一定时间后,仍保持增殖能力和生物活性,移植到大鼠周围神经损伤局部后可长时间存活,并通过持续分泌NGF起到促进周围神经修复的作用.     

毛囊干细胞对坐骨神经损伤修复的影响

背景:毛囊干细胞具有多分化潜能,可分化成神经细胞,极有希望成为治疗周围神经损伤的种子细胞。目的:观察毛囊干细胞对坐骨神经损伤修复的影响。方法:体外分离培养SD大鼠乳鼠胡须处的毛囊干细胞,经鉴定备用。36只SD大鼠随机分为实验组和对照组,建立坐骨神经损伤模型后,实验组于坐骨神经损伤处的上方注入浓度约106L-1的毛囊干细胞50μL,对照组注射等量的磷酸盐缓冲液。结果与结论:各组坐骨神经功能指数均随观察时间进行性增加,其中实验组大鼠神经功能恢复早于对照组;免疫组织化学检测移植后的毛囊干细胞大量存活并分化成神经细胞。结果提示毛囊干细胞能够有效的促进损伤的坐骨神经修复。     

Effects of physical exercise on the functional recovery of rat hindlimbs with impairments of the sciatic nerve as assessed by 2D video analysis

[Purpose] The purpose of this study was to investigate the effects of treadmill training on functional recovery by analyzing the ankle joint as well as the knee and hip joints with 2D video analysis during gait by rats with sciatic nerve injury. [Subjects and Methods] Twenty-four male Sprague-Dawley rats were used in this study. The sham group (SG) received only a sham operation without any sciatic injury; the training group (TG) performed treadmill training for 4 weeks after sciatic injury; and the control group (CG) wasn’t provided with any therapeutic intervention after sciatic injury. [Results] The ankle, knee, and hip ROM of TG and CG during the initial, mid stance, and toe-off phases of gait at post-test were significantly different from SG. [Conclusion] Physical exercise, like treadmill training, is beneficial for the improvement of the ankle, knee and hip joints of rats with crushed sciatic nerve injury.Key words: Sciatic nerve injury, Physical exercise, 2D video analysis