嗅神经鞘细胞移植恢复大鼠损伤脊损的功能

为探讨嗅神经鞘细胞移植恢复大鼠损伤脊髓的功能，将成年大鼠分为脊髓半切洞损伤组（A组）和脊髓半切洞损伤－嗅神经鞘细胞移植组（B）组手术后应用联合行为评分（CBS）感觉诱发电位（SEP）和运动诱发电位（MEP）检查，测定脊髓功能恢复情况，结果2组CBS得分，A组＞B组，SEP和MEP潜峰时均A组＞B组，统计学分析均有显著性差异（P＜0．05），表明移植嗅神经鞘细胞能恢复损伤脊髓的功能。     

大鼠脊髓楔型半切空洞模型的建立及评估

摘要: 目的建立一种新型大鼠脊髓半切模型,为临床脊髓空洞损伤研究提供适宜的动物模型。方法25 只SD 大鼠随机分为脊髓楔型块状半切组( A 组,n = 10) 、假手术组( B 组,n = 10) 和正常对照组( C 组,n = 5) 。术后采用 BBB 运动功能评分、斜板试验、HE 染色和核磁共振( MRI) 检测综合评价脊髓半切模型的稳定性。结果术后A 组 大鼠伤侧后肢BBB 运动功能评分及斜板维持最大角度值显著低于B 组和C 组( P ＜ 0. 05) ,而这些指标在B 组和C 组之间没有明显差异; 术后28 d HE 和MRI 检测显示脊髓损伤区( A 组) 灰质和白质发生明显的形态学改变。结论 通过该方法建立的脊髓半切模型稳定、可靠,适于脊髓空洞性损伤的研究。     

MicroRNA-124a对SCI继发性损伤的影响及相关机制研究

探究microRNA-124a(miR-124a)对脊髓损伤(spinal cord injury,SCI)继发性损伤的影响及相关机制.取90只健康成年Wistar大鼠建立SCI模型,随机分为3组,第1组术后仅注射生理盐水,为未治疗组;第2组术后注射骨髓基质细胞源神经干细胞(BMSCs-D-NSCs)治疗,为正常移植组;第3组术后注射携带miR-124a的骨髓基质细胞源神经干细胞(miR-124a-BMSCs-D-NSCs),为转染移植组.另选取60只健康成年Wistar大鼠作为对照组,仅给予假手术处理.采用HE染色观察大鼠的组织形态学变化,采用实时荧光定量PCR技术检测大鼠的miR-124a表达情况,并对损伤灶进行显微测量计算,比较脊髓功能恢复的BBB评分情况及脊髓组织损伤大小的情况.结果显示,SCI后,脊髓组织中miR-124a基因表达显著降低,脊髓神经功能也明显降低,miR-124a-BMSCs-D-NSCs能够有效地改善SCI,减少脊髓损伤组织范围及体积,还能改善中枢神经的功能.     

骨髓间充质干细胞移植对脊髓损伤大鼠功能和结构修复的实验研究

观察骨髓间克质干细胞（MSC）移植对脊髓中度损伤大鼠运动功能的修复作用。方法：20只成年Sprague—Dawley（SD）大鼠随机移植组（n=10）和对照组（n=10）两组,均采用改良的A11en’s打击法遣成脊髓中度损伤（致伤冲量10g×4cm）。伤后1周,移植组于伤处移植大鼠MSC,而对照组仅注射等量PBS。分别于移植后1天,1周,2周,3周、4周用BBB评分观测大鼠的运动功能,并于移植后4周进行损伤脊髓的大体观察和组织学检测。结果：移植后1周两组动物运动功能恢复无明显差异。移植后2周、3周、4周,与对照组比较,移植组显著提高运动功能。移植后4周,移植组损伤脊髓的结构修复明显优于对照组。结论;脊髓损伤大鼠经MSC移植后能明显改善其运动功能和神经形态,MSC移植对脊髓损伤大鼠有治疗作用。     

大鼠脊髓不同平面双侧半横切损伤模型的建立及评价

目的建立一种新型大鼠脊髓切割损伤模型,为临床脊髓不同平面损伤研究提供适宜的动物模型。方法45只SD大鼠随机分为脊髓不同平面双侧半横切组(A组,n=15)、脊髓全横切组(B组,n=15)和假手术组(C组,n=15)。术后观察、记录各组大鼠活动、进食水、排尿排便、切口感染等并发症和死亡情况,采用BBB运动功能评分和斜板试验评价大鼠行为学功能。结果术后A组大鼠活动、进食水量减少,53.33%大鼠出现尿潴留,40.00%大鼠于术后1~4周死亡;B组大鼠活动、进食水量明显减少,66.67%大鼠出现尿潴留,60.00%大鼠于术后1~4周死亡;C组大鼠活动、进食水量无明显变化,无并发症及死亡发生。BBB运动功能评分及斜板维持最大角度值检测显示,A、B组均低于C组(P0.05),而这些评价指标在A组和B组之间无显著差异。结论脊髓不同平面双侧半横切损伤模型大鼠尿潴留及死亡率低,行为学评价与脊髓全横切损伤模型类似,适于脊髓不同平面双侧损伤修复的研究。     

大鼠肠系膜与肾被膜下移植胰岛治疗糖尿病的疗效对比

目的:探讨经大鼠肠系膜与肾被膜下移植胰岛在糖尿病治疗中的疗效对比与新路径.方法:采用链脲佐菌素诱导SD大鼠制作糖尿病模型,随机分为肠系膜部胰岛移植组(肠系膜组)和肾被膜下胰岛移植组(肾被膜组),各18只. V型胶原酶消化供体大鼠胰腺,Ficoll密度梯度法分离、纯化胰岛,双硫腙和台盼蓝染色检测胰岛纯度和活性.移植术后于不同时间点监测两组大鼠血糖波动、血清C肽水平及腹腔糖耐量功能,记录胰岛存活时间并切取移植部位行HE染色观察组织形态学改变.结果:每只供体大鼠获取(347. 08±33. 22)胰岛当量,胰岛纯度为(88. 03±4. 94)%,存活率为(90. 55±3. 98)%.两组大鼠血糖于移植后3 d降至正常水平,与移植前相比明显下降(P 0. 05);高糖刺激实验表明,移植后10、31 d两组大鼠刺激后的血清C肽水平均较刺激前上升(P 0. 05);腹腔糖耐量结果提示,两移植组大鼠糖耐受功能均良好(P 0. 05);肠系膜组与肾被膜组移植胰岛的中位存活时间分别为61 d与46 d; HE染色显示移植部位可见伴生血管的成团胰岛细胞.结论:经肠系膜移植胰岛能安全有效地发挥降糖作用,恢复糖尿病大鼠正常血糖水平,疗效优于肾被膜下移植.     

BMP7治疗大鼠脊髓损伤后NF200及GFAP表达的变化

目的探索BMP7促进大鼠急性脊髓损伤后运动功能恢复的作用,进一步研究BMP7对脊髓损伤处NF200及GFAP蛋白表达量的影响。方法实验用Wistar大鼠随机分为对照组和BMP7实验组,使用Allences's打击器建立大鼠T10节段脊髓损伤模型,BMP7实验组大鼠造模成功后连续7 d于脊髓损伤处注射50 ng BMP7,对照组造模成功后连续7 d于脊髓损伤处注射等体积的0.9%氯化钠注射液。2组大鼠分别于术后6 h、3 d、1 w、2 w、4 w、8 w进行BBB评分检测大鼠脊髓损伤后运动功能恢复情况,进行免疫组化实验检测损伤节段脊髓组织中NF200及GFAP蛋白表达量的变化。结果 BBB评分结果显示在1、2、4 w及8 w时BMP7实验组大鼠BBB评分均高于对照组,差异具有统计学意义(P0.05);免疫组化结果表明BMP7实验组大鼠脊髓损伤处NF200阳性表达细胞数在造模3 d后逐渐增多,至第4 w时达到高峰,且在1、2、4 w及8 w时均大于对照组,差异具有统计学意义;BMP7实验组及对照组GFAP阳性表达细胞数变化均不明显,两组间阳性细胞数差异不显著。结论 BMP7可以促进大鼠急性脊髓损伤后运动功能的恢复,BMP7可以上调脊髓损伤处NF200蛋白的表达量。     

基因重组碱性成纤维细胞生长因子对大鼠脊髓损伤神经保护作用

目的 :探索碱性成纤维细胞生长因子 (bFGF)对大鼠脊髓损伤的神经保护作用 方法 :将吸入bFGF的胶原蛋白海绵或空白海绵贴敷于大鼠脊髓损伤处 ,术后 1、2、3周 ,对大鼠机能进行评分 ,并对大脑运动皮质进行电镜观察分析 结果 :术后 1、2、3周 ,bFGF组大鼠运动评分均明显优于对照组 (Ρ <0 .0 5) ,运动皮质电镜结果显示bFGF组线粒体、内质网轻度肿胀 ,神经毡结构正常 ,无明显胶质细胞增生 程度较对照组明显减轻 结论 :bFGF对大鼠脊髓受损神经纤维起源脑区—运动皮质的神经细胞具有明显的保护作用 ,进而使大鼠运动功能受损明显减轻     

远红外陶瓷微珠干预对急性损伤大鼠LZM、MPO、IL-8和IL-10指标影响的研究

利用远红外陶瓷微珠作为干预手段,对大鼠肌肉急性损伤后进行恢复治疗,探讨其对骨骼肌血清炎症指标LZM、MPO和免疫学IL-10、IL-8指标的影响.将88只SD雄性大鼠分为A组安静对照组; B组模型组; C组模型+热水组; D组模型+陶瓷微珠组,大鼠急性损伤造模成功后自然休息48 h后,各组实验大鼠按照设计分别取干预后第3 d、4 d、6 d、7 d时相点数据进行组内、组间分析.结果:(1)干预后第3 d,D组血LZM、IL-10恢复后各时相水平均显著高于自然恢复B组与模型C组(P 0. 05);(2)干预后7 d,D组血MPO、IL-8恢复水平均显著低于自然恢复B组与模型C组(P 0. 01).结论:(1)远红外陶瓷微珠干预下,发现降低了MPO水平而提升了LZM水平,说明干预后急性损伤炎性细胞对损伤肌肉的破坏进一步减小;(2)远红外陶瓷微珠干预可提升IL-10浓度水平和降低IL-8的浓度水平,验证其影响炎症反应过程,促进急性损伤的快速恢复.     

骨髓间充质干细胞与内皮祖细胞对大鼠大部分肝切除合并缺血再灌注后损伤影响

目的通过制造大鼠肝脏缺血再灌注损伤合并大范围肝切除模型,探讨将骨髓间充质干细胞(BM-MSCs)与骨髓内皮前体细胞(BM-EPCs)分别经门静脉移植入模型肝内,观察其对于鼠肝脏缺血再灌注肝损伤修复和肝脏再生中的作用,以及将两种细胞联合移植观察两种细胞是否存在协同作用促进肝脏缺血再灌注损伤修复和肝脏再生。方法通过细胞贴壁法从骨髓液中获得BM-MSCs和BM-EPCs。利用慢病毒携带绿色荧光蛋白(GFP)及红色荧光蛋白(RFP)分别对BM-MSCs及BM-EPCs进行细胞标记,为下一步将细胞移植入动物体内观察细胞的分布情况做准备。制作SD大鼠70%肝缺血再灌注损伤合并大范围肝切除手术模型,将SD大鼠随机分为四组:单独注射BMMSCs(n=12)、单独BM-EPCs(n=12)、联合注射BM-MSCs+BM-EPCs组(n=12)、单独注射PBS空白对照组(n=12),按不同分组进行细胞移植,分别经大鼠门静脉注射GFP标记的BM-MSCs/200μL、RFP标记的BM-EPCs/200μL、BM-MSCs+BM-EPCs(BM-MSCs∶BM-EPCs=1∶1)/200μL、对照组注射PBS/200μL。以上四组分别在不同的时间段:术后第1天(n=4),第2天(n=4),第3天(n=4)各取腔静脉血检测血清AST、ALT及TNF-ɑ水平指标。肝脏组织做冰冻切片后利用免疫荧光方法动态观察BM-MSCs和BM-EPCs在肝脏内的分布。各组肝脏组织行常规病理切片观察肝脏病理损害及恢复的程度。最后各组取第3天的肝组织使用Tunnel法检测肝内细胞凋亡情况。结果与对照组比较,BM-MSCs组、BM-EPCs组、BM-MSCs+BM-EPCs组在肝缺血再灌注损伤合并大部分肝切除术后第1天、第2天、第3天大鼠血清AST及ALT、TNF-ɑ水平均明显下降(P0. 05),其中BM-MSCs组大鼠血清AST及ALT、TNF-ɑ水平均最低(P0. 05)。通过免疫荧光方法观察BM-MSCs及BM-EPCs可以特异性分布至肝脏损伤部位促进肝脏组织修复再生。肝组织HE染色病理及评分显示与对照组比较,BM-MSCs组、BM-EPCs组及BMMSCs+BM-EPCs组肝内细胞损伤程度明显降低,然而与BM-MSCs+BM-EPCs组相比较,BM-MSCs组和BM-EPCs组肝内细胞损伤程度明显降低(P0. 05),BM-MSCs组与BM-EPCs组相比较肝内细胞损伤程度无统计学意义。与对照组比较BM-MSCs组、BM-EPCs组及BM-MSCs+BM-EPCs混合组均能降低肝内细胞的凋亡数量,但BM-MSCs组肝内凋亡细胞数量最少(P0. 05)。结论单独细胞移植组与联合移植组均对肝脏大部分切除合并缺血再灌注损伤起保护作用。但在本实验中联合移植组对肝功能以及肝内细胞的保护并未体现出协同作用。BM-MSCs和BM-EPCs可能通过降低血清TNF-ɑ水平抑制炎症反应从而在大部分肝切除合并肝缺血再灌注损伤后保护肝内细胞。     

Morphological and electrophysiological evidence for regeneration of transected spinal cord fibers and restoration of motor functions in adult rats

The evoked potentials are regarded as an efficientindex to evaluate the functional status of a nervoussystem[1]. When stimulating the motor area of cerebralcortex with transcranial magnetic stimulation, elec-tronic signals can be obtained at the spinal co…     

Tropic1808基因重组蛋白对损伤坐骨神经脊髓细胞凋亡的影响

探讨Tropic1808基因重组蛋白对损伤坐骨神经的新生大鼠脊髓细胞凋亡影响,将新生SD大鼠一侧坐骨神经切断后,用无菌止血海绵包裹断离的神经近侧端,海绵内加入Tropic1808基因重组蛋白,阳性用神经生长因子、阴性用生理盐水作为对照;术后3、6、12h经TUNEL法染色,在光镜、电镜和图像分析系统下,了解L4－L5段脊髓细胞凋亡情况。得到生理盐水组的脊髓出现大量绸亡细胞;Tropic1808基因重组蛋白组凋亡细胞数量较生理盐水组显减少;Tropic1808基因重组蛋白组与神经生长因子组之间凋亡细胞数量的差别无显性意义。说明Tropic1808基因重组蛋白有保护受损神经组织,减少细胞凋亡的作用。     

补阳还五汤对脊髓损伤大鼠体重及后肢运动功能的影响

目的探讨补阳还五汤对脊髓损伤大鼠体重及后肢运动功能影响与其神经保护作用的关系。方法采用Allen’s打击法制作中度SCI模型,应用SPF级Wistar大鼠,随机分为4组：正常组和3个模型组,即模型空白组、BYHWD组、金纳多组,每组16只大鼠。模型组大鼠分别给予蒸馏水、BYHWD、金纳多水溶液,正常组给予蒸馏水,分别于造模前即0 d、造模后3 d、1 w、2 w、3 w,称量大鼠体重,并进行后肢运动功能评价,灌胃治疗2 w后,结束实验。结果SCI模型大鼠于造模后3 d体重及后肢运动功能均明显降低,灌胃治疗后,模型空白组大鼠体重缓慢增加,但后肢运动功能无明显改善;BYHWD组及金纳多组大鼠体重及后肢运动功能均有显著改善,且BYHWD组改善效果更明显,与金纳多组比较差异有显著性。结论BYHWD通过保护SCI大鼠脊髓组织,显著改善大鼠后肢运动功能,增加大鼠体重,为其治疗中医＂痿证＂提供了新的实验依据。     

Same impact momentum causes different degrees of spinal cord injury

The weight-drop impact is widely used in making animal model of spinal cord injury （SCI）. But there has not yet been an appropriate unit for the quantification of the impact. In this study, we compared the degrees of the spinal cord injury caused by weight-drop impact with the same momentum but different combinations of drop weight and drop height, in order to test whether ＂momentum＂ is capable of being the unit for the quantification of weight- drop impact. Thirty adult rats were randomly allocated to three groups and were injured with 5 g-10 cm （group A）, 10g-2.5 cm （group B） and 15 g-l.ll cm （group C） impacts with the same momentum to the spinal cord, respectively. Open-field locomotor function was evaluated using the Basso-Beattie-Bresnahan （BBB） locomotor rat- ing scale. The percentage of spared tissue area （STA） at the epicenter, and 500, 1000 and 1500 gm from the epicenter was calculated using serial sections stained by hematoxylin and eosin. As a result, the behavioral recovery （BBB scores） and the STA percentage were similar in group B and group C. However, the BBB score in group A was significantly lower than that in groups B and C at the same time point post injury. The STA percentage was signifi- cantly less and the lesion/cavity length was significantlygreater in group A than in groups B and C. These suggested that the 5 g-10 cm weight-drop impact, compared with the other two impacts with different weights and heights, caused a greater damage of the spinal cord when the momentum was the same. So, these impacts with the same momentum but different weights and drop heights cause different degrees of spinal cord injury. Momentum alone is inadequate to be the unit for the qualification of weight- drop impact and to be used to predict the extent of injury.     

Preliminary animal studies on observation of injured spinal cord with intraoperative ultrasound backscatter microscopy

Many studies have shown that strategies of nerve regeneration and cell-based transplantation are valid based on animal models of spinal cord injury (SCI).To apply these strategies and bridge spinal cord defects,the identification and precise localization of lesions during spinal cord surgery is necessary.The aim of the present experiment was to evaluate the capabilities of ultrasound backscatter microscopy (UBM) in identifying morphologic changes after SCI.After laminectomy,high-resolution ultrasound images of the spinal cord were obtained in one normal and seven spinal cord-injured adult Wistar rats using a UBM system with a 55-MHz center frequency scanner.Comparison between histoanatomic and UBM images was also performed.The results showed that UBM can identify cysts after the experimental SCI is removed in adult rats.In addition,the glial scar formed in secondary injury showed obvious hyperechoic speckle in the UBM image and correlated with the histoanatomic image.UBM has obvious clinical value in nerve regeneration and cell-based transplantation strategies in injured spinal cords.     

Effect of Jiaji electroacupuncture in transected rat spinal cord

We evaluated the effect of Jiaji electroacupuncture on cell proliferation and the expression of markers of endogenous neural stem cell activation after complete spinal cord transection. Female Wistar rats were assigned to 4 groups (n = 24 each): a sham-operated group, a control group, a Jiaji electroacupuncture group, and a Jiaji electroacupuncture preconditioning group. Motor function was significantly improved in the acupuncture groups compared to the control group at 7 and 14 d. Numbers of bromodeoxyuridine (BrdU)-, nestin-, and glial fibrillary acidic protein (GFAP)-positive cells were significantly greater in the acupuncture groups than in the controls at each time point. Expression of nestin and GFAP mRNA was significantly higher in the acupuncture groups than in the controls at each time point. Thus, Jiaji electroacupuncture and preconditioning may promote the proliferation of endogenous neural stem cells after spinal cord transection.     

Spinal cord decompression reduces rat neural cell apoptosis secondary to spinal cord injury

Objective: To determine whether spinal cord decompression plays a role in neural cell apoptosis after spinal cord injury. Study design: We used an animal model of compressive spinal cord injury with incomplete paraparesis to evaluate neural cell apoptosis after decompression. Apoptosis and cellular damage were assessed by staining with terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate nick-end labelling (TUNEL) and immunostaining for caspase-3, Bcl-2 and Bax. Methods: Experiments were conducted in male Sprague-Dawley rats (n=78) weighing 300~400 g. The spinal cord was compressed posteriorly at T10 level using a custom-made screw for 6 h, 24 h or continuously, followed by decompression by removal of the screw. The rats were sacrificed on Day 1 or 3 or in Week 1 or 4 post-decompression. The spinal cord was removed en bloc and examined at lesion site, rostral site and caudal site (7.5 mm away from the lesion). Results: The numbers of TUNEL-positive cells were significantly lower at the site of decompression on Day 1, and also at the rostral and caudal sites between Day 3 and Week 4 post-decompression, compared with the persistently compressed group. The numbers of cells between Day 1 and Week 4 were immunoreactive to caspase-3 and B-cell lymphoma-2 (Bcl-2)-associated X-protein (Bax), but not to Bcl-2, correlated with those of TUNEL-positive cells. Conclusion: Our results suggest that decompression reduces neural cell apoptosis following spinal cord injury.     

人神经营养因子-3在哺乳动物细胞中瞬时表达和稳定表达的初步研究

将人神经营养因子－3全长cDNA克隆入真核表达载体pcDNA3,分别COS-7儿CHO细胞中获得了瞬时表达和稳定表达，经大乳鼠脊髓背根神经节测活，瞬时表达和稳定表达产物均能明显促进其神经突起的生长，瞬时表达量约为10^-7g/mL，稳定表达量可达10^-8g/mL。     

Whisker movements evoked by stimulation of single pyramidal cells in rat motor cortex

Neuronal activity in the motor cortex is understood to be correlated with movements, but the impact of action potentials (APs) in single cortical neurons on the generation of movement has not been fully determined. Here we show that trains of APs in single pyramidal cells of rat motor cortex can evoke long sequences of small whisker movements. For layer-5 pyramids, we find that evoked rhythmic movements have a constant phase relative to the AP train, indicating that single layer-5 pyramids can reset the rhythm of whisker movements. Action potentials evoked in layer-6 pyramids can generate bursts of rhythmic whisking, with a variable phase of movements relative to the AP train. An increasing number of APs decreases the latency to onset of movement, whereas AP frequency determines movement direction and amplitude. We find that the efficacy of cortical APs in evoking whisker movements is not dependent on background cortical activity and is greatly enhanced in waking rats. We conclude that in vibrissae motor cortex sparse AP activity can evoke movements.