共查询到19条相似文献,搜索用时 78 毫秒
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重组腺相关病毒介导NgRDN基因促进损伤后视神经轴突再生的实验研究 总被引:1,自引:0,他引:1
目的探讨大鼠视网膜神经节细胞(RGC)内转染含NgR^DN的重组腺相关病毒(AAV)后对视神经损伤后再生的影响,并观察其与晶状体损伤及巨噬细胞激活之间的关系。方法将45只Wistar大鼠随机分为3组,A组为玻璃体注射携带绿色荧光蛋白(EGFP)的AAV—EGFP组,B组为玻璃体注射AAV—NgR—EGFP组,C组为玻璃体注射AAV—NgR^DN-EGFP组,3种病毒滴度均为5×10^11v.g/ml。每组又分3个亚组,各亚组5只大鼠,1组为玻璃体内注射rAAV组,2组为玻璃体内注射rAAV+晶状体损伤组,3组为玻璃体内注射rAAV+酵母多糖组。于玻璃体内注射rAAV后3周进行视神经夹伤,并于夹伤后4d取右眼视网膜进行植片培养,通过βⅢ微管蛋白染色检测视网膜植块边缘的轴突生长情况;于夹伤后2周进行视神经生长相关蛋白(GAP)-43染色,观察视神经轴突再生情况。结果视网膜植片βⅢ-微管蛋白染色表明,在无髓磷脂培养条件下,AAV—NgR—EGFP、AAV—NgR^DN-EGFP对RGC的轴突再生无影响:而在含髓磷脂培养条件下,即模拟体内RGC的轴突生长环境,B组的轴突再生数量(13个4个)还是长度(36μm±4μm)均低于A组(均P〈0.01);C1组与A1组比较差异无统计学意义,C2和C3组轴突再生的数量及长度均分别高于A2和A3组,C2组(317个±45个、508μm±44μm)更高于C3组(238个±30个、365μm±48μm,均P〈0.01);视神经GAP-43染色表明,B组视神经轴突再生明显低于A组,c1组轴突再生与A1组差异无统计学意义.而C2和C3组轴突再生显著高于A2和A3组。结论玻璃体内转染AAV—NgR^DN-EGFP同时使RGC处于激活状态可以促进视神经的轴突再生,NgR^DN可以有效拮抗NgR的作用。 相似文献
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激肽系统即激肽释放酶-激肽系统(Kallikrein-kinin system,KKS)广泛存在于动物体内的多个系统内。近年来,许多基础实验和临床研究表明,在脑缺血后激肽释放酶-激肽系统被激活,通过促进局部血管再生和神经再生、抑制细胞凋亡、促进神经胶质细胞迁移等作用,对急性缺血性脑血管疾病有保护作用。深入研究KKS的作用为缺血性脑血管病的治疗提供了又一新的途径。 相似文献
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激肽释放酶-激肽系统主要由激肽原、激肽释放酶和激肽组成,该系统在心肌梗死和缺血损伤后血管新生中发挥重要作用。激肽及其受体B1和B2在急性心肌梗死后发挥保护作用,并能促进缺血下肢的血管新生过程。高分子量激肽原的水解产物HKa在血管新生过程中发挥负性调节作用,抑制内皮细胞的增殖和黏附,诱导其发生凋亡。此外,激肽及其受体B1和B2在新生血管形成中发挥一系列的正性调节作用,促进内皮祖细胞的募集和迁移。作者对激肽释放酶-激肽系统在缺血损伤后血管新生中的作用研究进展作一综述。 相似文献
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神经生长因子对视网膜神经节细胞的保护和修复作用 总被引:1,自引:0,他引:1
视神经作为中枢神经系统一部分,由于其在损伤后缺乏神经修复和再生所需的微环境,因此视神经损伤后的治疗和功能的恢复是临床上的一大难题.而神经再生潜能是在适宜的微环境条件下发生轴突侧支出芽和突触重建和在周围神经系统提供的微环境适宜条件下中枢神经才会再生.若将周围神经移植到受损的中枢神经局部,改变中枢神经的微环境即能显著促进中枢神经再生.新近研究表明,神经生长因子(NGF)能促进轴突切断和缺血后视网膜神经节细胞(RGCs)的存活以及损伤后部分轴突的再生和保护变性疾病中的光感受器.它不仅是神经细胞增殖和分化的重要调控因子.而且可以成为变性视网膜疾病、缺血性视神经病变、视网膜脱离复位术后视功能差者以及视神经损伤后有效的治疗剂. 相似文献
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人胰激肽释放酶基因的克隆及融合蛋白的表达 总被引:1,自引:0,他引:1
目的开发激肽释放酶基因工程产品,为开展基因治疗高血压奠定基础。方法提取人胰腺组织总RNA,逆转录后PCR扩增激肽释放酶cDNA。回收、补平后插入质粒KS,构建出中间载体KSKK,酶切鉴定后双向测序分析激肽释放酶基因序列。从KSKK中切出激肽释放酶原及激肽释放酶基因,插入真核表达载体PET-28b(+),经酶切鉴定后,进行核苷酸序列分析和融合蛋白表达。结果本实验克隆的激肽释放酶基因与GenBank报告的激肽释放酶基因相比,有一个碱基不同,同源性为99.8%。将IPTG诱导表达进行SDS—PAGE电泳,与蛋白标准品比较在31800处可见明显的高表达带。免疫印迹实验表明重组蛋白具有KK的抗原性。结论已成功克隆并表达了人组织激肽释放酶基因,为进一步开发基因工程产品及进行基因治疗高血压研究奠定了基础。 相似文献
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目的:探讨银杏内酯B对视神经钳夹伤后大鼠视网膜神经节细胞(RGCs)的保护作用。方法:取出生后42 d的SD大鼠36只,随机抽取12只为A组(正常对照组);24只分离暴露视神经并进行视神经钳夹后随机分为B组(模型组)和C组(GB治疗组),每组12只。每只鼠的右眼用于实验。A组不作任何处理,B、C组分别于实验前1周每日腹腔注射相应体积生理盐水和银杏内酯B(GB)40 mg/kg,术后继续给药1周,术后1、2周分别行闪光视觉诱发电位和HE染色光镜检查,并计数术后2周视网膜垂直经线RGCs数。结果:术后1周,A、B、C三组的LPl和APl分别为[(90±4)ms,(19±3)μV]、[(110±6)ms(,11±3)μV]和[(94±4)ms(,18±2)μV],B组与A、C组比较差异有统计学意义(P<0.05);术后2 w,A、B、C三组的LPl和APl分别为[(92±11)ms,(21±3)μV]、[(186±15)ms,(7±2)μV]和[(104±12)ms,(14±3)μV],RGCs数目分别为(281±39)个、(112±20)个、(228±35)个,各指标A、B、C三组比较差异均有统计学意义(P<0.05)。结论:银杏内酯B能抑制部分大鼠视神经钳夹后RGCs凋亡,具有一定的视神经保护作用。 相似文献
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目的:观察左归丸对视神经夹伤大鼠视网膜神经节细胞的保护作用。方法:建立大鼠单侧视神经部分损伤模型。模型大鼠分别给予左归丸液4.0g/(kg·d)(治疗组)和等量生理盐水(损伤对照组)灌胃,采用免疫组织荧光技术于损伤后第1、2、4、8和16周检测受损眼视网膜神经节细胞数目及神经上皮干细胞蛋白(nestin)、胶质纤维酸性蛋白(glial fibrillary acidic protein,GFAP)的表达情况。结果:视神经夹伤后,大鼠视网膜节细胞数目减少,细胞排列疏松紊乱,在内、外网层和内核层可见裂隙形成,视网膜厚度较正常组变薄,以伤后第4周最为严重,神经节细胞减少约50%,至第8周后神经节细胞减少缓慢。视神经夹伤第2周时,nestin和GFAP表达明显升高,持续至损伤后第8周。Nestin和GFAP在视网膜全层均有表达,但在神经节细胞层、内网层和内核层表达最强,呈条带状弯曲或蛇样匍行;伤后第4周时表达最强,此后二者表达下降,至伤后第16周时,GFAP先于nestin蛋白降至正常水平。各时间点左归丸组神经节细胞存活数比损伤对照组增加,且细胞排列相对整齐;nestin和GFAP表达强度较损伤对照组增加(P〈0.05)。结论:左归丸可能通过促进大鼠视网膜Mller细胞nestin和GFAP的表达,维持损伤后视网膜结构的完整性,从而间接减少节细胞凋亡,有效保护受损视网膜节细胞。 相似文献
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目的:观察佐剂性关节炎( AA)大鼠血浆激肽释放酶-激肽系统( KKS)的活化情况,并探讨PKSI-527对大鼠关节炎及全身炎症的影响。方法采用弗氏完全佐剂建立AA大鼠模型,并通过测量足爪肿胀以及炎症反应评分的方法进行半定量评价。 ELISA法检测血浆中KKS相关指标血浆前激肽释放酶(PK)、高分子量激肽原(HK)及缓激肽(BK)的水平,实时荧光定量 PCR 检测外周血 BK 受体 B1R、B2R mRNA的表达情况。使用 PKSI-527腹腔内注射,观察抑制剂对AA大鼠KKS活化以及关节肿胀和全身炎症的改变情况。结果 AA大鼠表现继发性足爪肿胀、关节和全身的炎症反应,与正常大鼠比较,其血浆内BK、HK显著升高( P<0.05),PK未见明显升高;同时外周血B1R、B2R mRNA表达水平亦较正常大鼠出现上调,差异有统计学意义(P <0.05)。注射PKSI-527可显著降低 AA大鼠血浆BK、 HK、PK以及B1R、B2R mRNA的水平,与溶剂组比较,差异有统计学意义( P<0.05)。 PKSI-527注射后关节肿胀较溶剂组大鼠明显减轻,差异有统计学意义(P<0.05),关节炎指数以及全身评分也有下降趋势。结论 KKS在AA大鼠体内处于活化状态,使用KKS抑制剂PKSI-527能够明显改善AA大鼠的关节炎和全身的炎症程度。 相似文献
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The most common irreversible blindness diseases are age-related macular degeneration,glaucoma,and diabetic retinopathy which involve the optic nerve or retina.These diseases share a common condition of causing blindness-progressive neural cells loss of retina (photoreceptor cells,retinal ganglion cells (RGCs)).Although many advances in the treatment for these diseases have been achieved in recent years,the visual function often cannot be reversed.To improve the visual outcomes,the retinal neuron cells must be rescued.Optic nerve diseases including glaucoma were mostly studied for the effort to rescue the injured neurons and regenerate the neuron axons. 相似文献
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混合晶体蛋白对大鼠视神经损伤后轴突再生作用的研究 总被引:1,自引:0,他引:1
目的观察混合晶状体蛋白对LongEvans大鼠视神经损伤后轴突再生作用。方法大鼠双眼均行视神经钳夹,右眼为玻璃体腔注射晶状体蛋白眼,左眼为等渗盐水对照眼,WGA顺行示踪及F-VEP检查观察轴突再生情况和功能恢复情况。电镜评价轴突再生情况。结果玻璃体腔注射晶状体蛋白眼有更多轴突纤维尽快通过损伤区,晶状体蛋白能够促进F-VEP振幅恢复,电镜观察晶状体蛋白组于损伤点后5mm仍有较多的再生轴突。结论视神经钳夹伤后玻璃体腔注射可溶性混合晶状体蛋白能够促进轴突再生,并且能够部分的改善视功能。 相似文献
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Neuroprotective effect of recombinant human erythropoietin on optic nerve injury in rats 总被引:3,自引:0,他引:3
Background Optic nerve injury, caused by retinal and optic nerve diseases, can eventually result in vision loss. To date, few effective treatments have been discovered to restore visual function. Previous studies showed that recombinant human erythropoietin (rhEPO) has a neuroprotective effect on the central nervous system, particularly in nerve injury. In this study, we investigated the effects of rhEPO on axonal regeneration and functional restoration following optic nerve injury. This was done by measuring the expression of growth associated protein 43 (GAP-43), a marker for neuronal regeneration, on the retina and flash-visual evoked potential (F-VEP). Methods Adult Wistar rats were randomly assigned to rhEPO and control (saline) groups. Optic nerve crush injury models were established and rhEPO or saline were immediately injected into the vitreous cavity. The expression of GAP-43 was detected by immunohistochemistry and the F-VEP was measured pre-injury, immediately after injury, 1 week and 2 weeks post-injury. Results No detectable staining for GAP-43 was observed in normal retina. In the control group, the level of GAP-43 expression was higher at 1 week post-injury, but decreased at 2 weeks. In the rhEPO group, the level of GAP-43 expression was notably higher at both 1 week and 2 weeks. At each time point post-injury, the expression of GAP-43 in rhEPO group was significantly higher than the control group (P 〈0.05). Obvious changes in F-VEP examination were detected immediately after optic nerve injury, including significantly prolonged latency and decreased amplitude of the P1 wave. In the control group, the changes were still obvious at 1 week. The latency was decreased and the amplitude had slightly recovered to 28.23% of the normal value at 2 weeks. In rhEPO group, there was significantly more recovery than the control group at 1 week and 2 weeks post-injury (P 〈0.05). The latency most close to the normal level and the amplitude had recovered to 65.51% of the normal value at 2 weeks. Conclusions rhEPO can prolong the expression of GAP-43 and increase its intensity after optic nerve injury, thereby promoting neural repair and axonal regeneration. Under the protection of rhEPO, the conduction velocity of the optic nerve recovered significantly. Therefore, rhEPO has neuroprotective effects on the optic nerve and promotes functional restoration of the optic nerve. Chin Med J 2009;122(17):2008-2012 相似文献
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ZHU Rui-lin CHO Kin-Sang GUO Chen-ying CHEW Justin CHEN Dong-feng YANG Liu 《中华医学杂志(英文版)》2013,126(13):2543-2547
Objective To review the functions of these intracellular signals in their regulation of retinal ganglion cell (RGC) axon regeneration.Data sources Relevant articles published in English or Chinese from... 相似文献
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目的:利用荧光金逆行标记评价视神经切断后视网膜节细胞(RGCs)的存活率。方法:将SD大鼠20只随机均分为4组,正常对照组和视神经切断后5d、7d和1dd组。用荧光金逆行标记和定量解剖学技术观察正常对照组和视神经切断后5d、7d和14d组RGCs的密度。结果:正常对照组RGCs呈放射状分布,边界清晰,可见明显细胞突起,无渗漏现象;视神经切断组RGCs随时间延长而减少,细胞分布不均匀,并且可见吞噬死亡细胞碎片和从死亡细胞渗漏的荧光金的小胶质细胞。正常对照组左眼与右眼RGCs密度差异无统计学意义(P〉0.05);视神经切断后RGCs进行性减少,切断后5d、7d和14d组左眼RGCs密度均明显低于正常对照组(P〈0.01),视神经切断后5d、7d和14d存活率分别为53%、38%和13%。结论:荧光金逆行标记是评价视神经切断后RGCs存活率有效的方法。 相似文献
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目的: 探讨腹腔注射银杏叶提取物(Ginkgo biboba extract,EGb 761)对豚鼠视神经横断伤后视网膜神经节细胞(retinal ganglion cell, RGC)形态及功能的保护作用。
方法: 75只白化豚鼠随机等分为正常对照组、假手术组、模型组、生理盐水组和EGb 761组。分离暴露豚鼠的右眼视神经并于球后1.0 mm处进行横断造模,正常对照组不作任何处理,假手术组仅分离暴露视神经。生理盐水组和EGb 761组分别于实验开始前1周每日腹腔注射1次相应体积生理盐水和EGb 761(100 mg/kg),术后继续给药4周。术后第4天,各组随机处死3只豚鼠,采用脱氧核苷酸转移酶介导的dUTP缺口末端标记(terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling, TUNEL)法检测RGC凋亡;分别于术后第14和28天进行图形视网膜电图(pattern electoretinogram, PERG)检查;摘取眼球作组织病理学检查并计数视网膜垂直经线RGC数目。
结果: 术后第4天,正常对照组、假手术组和EGb 761组均未见TUNEL阳性RGC,模型组和生理盐水组均见有TUNEL阳性RGC。术后第14和28天,模型组和生理盐水组RGC数目均少于正常对照组和假手术组(P〈0.05),EGb 761组少于正常对照组和假手术组(P〈0.05),但显著多于模型组和生理盐水组(P〈0.05);术后第14和28天,EGb 761组PERG的N95振幅较模型组和生理盐水组高(P〈0.05),与模型组和假手术组相近(P〉0.05)。RGC数目与N95振幅呈正相关(r=0.859, P=0.001 5)。
结论: 腹腔注射银杏叶提取物EGb 761能抑制豚鼠视神经横断后的RGC凋亡,对RGC的结构和功能具有保护作用。 相似文献
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目的:探讨神经再生素(NRF)对大鼠坐骨神经损伤后再生的影响.方法:SD大鼠30只,雌雄各半,随机分为3组:NRF低、高剂量组和空白对照组.分别于坐骨神经夹伤术后10、15、20 d测定大鼠坐骨神经功能指数(SFI),分离出大鼠双侧坐骨神经行电生理学检测,计算神经干动作电位恢复率;各组随机选取2只大鼠,应用透射电镜观察再生坐骨神经超微结构;其余大鼠行光镜下观察脊髓腰膨大(L4~L6)、夹伤远端处坐骨神经、损伤侧腓肠肌组织,并测定脊髓前角运动神经元数、再生有髓神经纤维数、腓肠肌肌细胞截面积等指标.结果:术后10 d各组SFI无显著差异,术后15 d仅仅高剂量组SFI明显优于对照组(P<0.01),术后20 d高、低剂量组SFI均优于对照组(P<0.01,P<0.05);术后20 d高、低剂量组及对照组大鼠坐骨神经干动作电位的恢复率分别为(57±26)%、(44±15)%、(31±9)%,其中高剂量组与对照组相比有显著差异(P<0.05);高剂量NRF组的有髓神经纤维成熟度优于对照组,而变性纤维少于对照组;光镜下NRF高剂量组再生神经纤维排列致密整齐、结构均匀,腓肠肌肌细胞饱满、排列整齐,双侧脊髓前角运动神经元更接近;NRF高剂量组脊髓前角运动神经元计数、有髓神经纤维计数均显著高于对照组(P<0.05,P<0.01),NRF高、低剂量组腓肠肌肌细胞截面积显著高于对照组(P<0.01,P<0.05).结论:NRF能促进坐骨神经再生及其功能恢复. 相似文献
18.
猪视网膜神经节细胞的培养及超微结构 总被引:3,自引:3,他引:3
目的:建立视网膜神经节细胞(retinal ganglion cells,RGCs)的体外培养方法,并研究视网膜不同类型神经细胞之间的相互作用,为RGCs的体外实验研究奠定基础。方法:进行猪视网膜细胞混合体外培养和神经节细胞的纯化培养,观察神经节细胞生长状态及轴突生长情况,研究视网膜不同类型神经细胞之间的相互作用。结果:视网膜细胞混合培养时,神经节细胞生长良好,纯化后的神经节细胞间连接减弱,细胞存活时间缩短。结论:视网膜细胞混合培养有利于神经节细胞的贴壁和生长。 相似文献
19.
This study aimed to modify the mixed and purified culture of rat retinal ganglion cells(RGCs) in vitro.The retinae of 1-3 day old Sprague-Dawley(SD) rats were separated bluntly into two layers:inner layer and outer layer,under a surgical microscope.Retinal cells isolated from different layers(inner layer,outer layer and whole retinal tissue) by using enzyme dissociation method were cultured in F12/DMEM medium containing 15% FBS.After 3-day culture,the RGCs in the retinal cells obtained from mixed culture of inner,outer,and whole retinal tissue were identified by immunocytochemical staining of Thy-1.1,and the rate of RGCs to retinal cells(RGCs%) was calculated.Two monoclonal antibodies,anti-macrophages/granulocytes(OX-41) against rat macrophage and antibody against rat Thy-1.1(OX-7),were used to purify RGCs by either a conventional or modified two-stepped immunopanning procedure(purification in situ).Purified RGCs were seeded at different cell density and cultured in F12/DMEM medium containing 15% FBS.Immunocytochemical staining for Thy-1.1,MTT,and PI-Hoechst33342 fluorescence imaging were used to identify the purity and the viability of RGCs in purified culture of RGCs.The results showed:(1) Immunocytochemistry of different retinal tissue layers culture revealed that the RGCs% was(19.9±1.2)%,(0.5±0.2)%,and(6.2±1.7)% respectively in the mixed culture of inner,outer,and whole retinal tissue,with differences being significant(P<0.05);(2) fluorescent double staining of Hoechst33342 and PI indicated that with the same RGCs%,RGCs obtained from purification in situ grew well with more neurite outgrowth than those by the conventional two-stepped immunopanning method;(3) the viability of purified RGCs seeded at high density was in-creased and the cells developed complex intercellular networks.The viability of RGCs was declined with the decreasing seeding density,and most cells presented round or oval in shape with thin neurites.It was concluded that:(1) RGCs% in the inner layer retina was higher than that in the outer layer retina;(2) RGCs obtained by in situ purification had more neurite outgrowth and lower mortality than those by conventional two-stepped immunopanning procedure;(3) the viability of purified RGCs could be increased by increasing cell seeding density to some extent. 相似文献