家兔面神经撞击伤后胶质细胞源性的神经营养因子mRNA在面神经元中的表达特点

目的:了解胶质细胞源性的神经营养因子(GDNF)mRNA在面神经撞击伤这一特定致伤条件下的表达特点, 结合其他学者的实验结果,探讨GDNF在面神经损伤后再生中可能发挥的生物学作用。方法:以撞击枪在10 m/s 撞击速度,715 J撞击能量下建立家兔面神经撞击伤模型,撞击后3、7、14、21 d采用原位杂交方法分别检测面神经元及周围面神经中GDNF mRNA的表达范围及表达特点,并对面神经元表达数量进行计数分析。结果:面神经受到撞击后在不同时间点的面神经元中均可检出强烈的GDNF mRNA表达,第7天达高峰,随后逐渐下降,至第21天仍可见较高水平表达。周围神经雪旺氏细胞及正常面神经元均不表达GDNF mRNA。结论:GDNF是一种应激性表达的运动神经元营养因子,其表达特点与面神经撞击伤后的再生过程在时间上具有一致性,表明它可能在面神经损伤后的再生过程中发挥作用。     

外源性BMP—2对家兔面神经创伤愈合过程中神经干传导速度作用的实验观察

目的 为研究面神经损伤后再生过程BMP－2对神经功能恢复的影响。方法 采用家兔的面神经压榨伤模型,以自身左右侧为对照,实验侧给予BMP－2,对照侧给予生理盐水,对两组面神经进行了神经传导速度的测定和组织形态学观察,结果 实验侧面神经组织学形态更接近正常,平均传导速度也略快于对照侧,而统计学检验无显著性差异,提示BMP－2可能对面神经的再生过程有一定的作用,但还不能确定这种作用是否能影响面神经功能的恢复。     

p75神经营养蛋白受体基因敲除对小鼠面神经损伤后神经再生的影响

目的探讨p75神经营养蛋白受体（p75NTR）在面神经损伤后神经再生中的作用。方法对p75NTR基因敲除小鼠和野生型129sv小鼠的一侧面神经总干在神经出颅2 mm处进行损伤,损伤后第2天,一部分小鼠在神经干损伤的近中侧注射霍乱毒素B（CTB）进行顺行示踪标记,损伤后3、7 d,应用免疫组织化学方法对神经纤维再生轴突进行长度测定及记数分析。另一部分小鼠在面神经总干损伤后第4天切断神经,将切断的面神经断端置入含有FastBlue的聚氯乙烯单端小管中进行逆行示踪标记,荧光显微镜下对面神经核运动神经元进行计数分析。结果p75NTR基因敲除小鼠与野生型129sv小鼠相比较,再生的神经纤维轴突长度明显不足,二者间面神经核再生运动神经元数量差异有统计学意义（P＜0.05）。再生轴突的免疫组织化学染色表明,p75NTR基因敲除小鼠再生的神经纤维轴突数量也明显降低（P＜0.01）。结论p75NTR基因可以增强面神经的再生。     

Laser welding of rat's facial nerve

The aim of this study is to compare regeneration of the severed nerves that were repaired by laser welding with those repaired by microsurgical suturing and evaluate the value in use of laser nerve welding in the head and neck area. In 12 rats the buccal branches of the facial nerves on the both sides were transected, and CO2 laser welding of the epineurium was performed on the right side and microsurgical suture technique was applied on the left side. In six rats Cholera Toxin B Subunit (CTb) was injected in the epineurium distal to the nerve anastomosis site at postoperative week 4. Another six rats were treated exactly in the same way in postoperative week 8. Six normal rats were used as controls. Intact facial nerve was observed after injection of CTb as well. Neurons of facial nuclei labeled positively by CTb were detected immunohistochemically, and the numbers were counted. CTb-positive neurons in the control group were 1311 +/- 258 (n = 6). CTb-positive neurons in the group (n = 6) with laser nerve welding were 1174 +/- 122 in postoperative week 4 and 1562 +/- 565 in postoperative week 8. CTb-positive neurons in the group (n = 6) with microsurgical suture were 1066 +/- 89 in postoperative week 4 and 1443 +/- 531 in postoperative week 8. CTb-positive neurons were seen significantly more in the group with laser welding than in the group with microsurgical suture in postoperative week (P = 0.028), but there was not much difference in postoperative week 8 (P = 0.463). None of 12 rats showed dehiscence at the nerve anastomosis done by laser welding. This study shows that nerve regeneration is more apparent in the nerve repaired by laser welding than in that repaired by microsurgical suture.     

bcl-2、Bax基因在面神经损伤后面神经元的表达及对神经元凋亡的调节

目的:探讨切断面神经干后面神经元bcl-2、Bax基因表达变化与面神经元细胞凋亡的关系。方法:将60只成年Wistar大白鼠左侧面神经干切断作为实验组,右侧面神经干未切断作为对照组。应用ABC免疫组化染色方法和原位末端标记法(TUNEL)观察术后3、7、15、21、30、60 d实验组与对照组面神经元内bcl-2、Bax基因的表达及面神经元凋亡的情况。结果:切断面神经干后3 d,bcl-2、Bax基因表达开始增多,21 d达高峰(P<0101),bcl-2/Bax比值达最低(P<0101);切断面神经干后3 d,实验组面神经元凋亡较对照组增多,21 d达凋亡高峰(P<0101)。结论:bcl-2、 Bax基因参与了面神经干切断诱导的面神经元凋亡过程的调控。     

睫状神经营养因子在面神经再生中的表达变化及TGF-β、rhBMP-2的调控

目的　探讨睫状神经营养因子(CNTF)在面神经切断后的免疫定位及转化生长因子β(TGF-β)及人重组骨形成蛋白2(rhBMP-2)对其的调控作用。方法　选取面神经切断后不同时期的面神经核组织切片,通过免疫组化染色和图像分析对比不同时期面神经核中CNTF的浓度变化。结果　面神经切断后,术后1 d CNTF就开始表达并逐渐增加,分别于术后1周和1月面神经核运动元中CNTF的含量达到最大。此后逐渐下降。rhBMP-2对CNTF的表达无明显作用,而TGF-β能促进神经再生过程中CNTF的表达。结论　内源性CNTF在神经再生过程中对神经轴突的延伸也具有一定的促进作用。TGF-β可通过促进CNTF的表达而对面神经运动神经元起着重要的保护作用。     

甲状腺激素对小鼠面神经损伤轴突再生及神经电生理功能的影响

目的:探讨甲状腺激素对小鼠面神经损伤轴突再生及神经电生理功能的影响.方法:将64只小鼠随机分为4组,即假手术组、模型组、甲状腺素组、甲状腺素+LY组,每组16只.除假手术组外,其余组均建立面神经损伤模型.术后苏醒开始干预,甲状腺素组于损伤处皮下注射50μg/kg中性甲状腺素溶液,甲状腺素+LY组在甲状腺素组基础上腹腔注...     

渐进性咬合紊乱对大鼠髁突软骨中骨形成蛋白2表达的影响

目的：探讨渐进性咬合紊乱所致大鼠髁突软骨改建中骨形成蛋白2（BMP-2）的变化情况及其意义。方法：建立幼年和成年大鼠渐进性咬合紊乱模型,应用免疫组化SABC法检测大鼠髁突软骨中BMP-2的表达变化,并作图像分析和统计学处理。结果：幼年和成年实验组大鼠左右侧髁突软骨中BMP-2的表达差异无统计学意义。与对照组相比,幼年和成年实验组中BMP-2的表达于实验4周时均低于对照组（P〈0.01）,之后出现回升,8周时两组均高于对照组（P〈0.05）。不同时间点比较,幼年与成年实验组中BMP-2的表达在2~8周的时间内均出现先降低再增高的趋势。结论：BMP-2参与了髁突软骨随咬合变化而发生的改建活动。     

去细胞异体面神经移植早期的组织学研究

目的组织学观察化学去细胞异体面神经移植修复家兔面神经缺损时，早期神经再生的变化。方法对72只家兔人为造成左侧面神经干及分支缺损2cm，分为去细胞异体面神经（A组）、自体面神经（B组）、去细胞异体腓神经（C组）、自体腓神经（D组）共4组，A组用去细胞异体面神经干外膜缝合以桥接缺损，B、C、D组作为对照。术后1、3、6个月取材行特殊三色染色、免疫组化染色以及透射电镜观察。结果术后6个月A组、B组的移植段内均有大量新生神经纤维及新生血管，可见大量的长梭形雪旺细胞纵形排列，两组在纤维数量及髓鞘厚度方面差别不明显。C、D组恢复效果差。结论异体面神经干移植术后6个月轴突的再生已通过远端吻合口，移植段再血管化及雪旺细胞增殖均良好。     

大鼠舌下神经压榨伤后p38MAPK的活化及外源性神经生长因子促神经再生作用的研究

目的检测舌下神经压榨损伤前后及神经生长因子（NGF）干预后磷酸化p38MAPK的表达,探讨p38MAPK在大鼠舌下神经损伤及干预后的作用和NGF对大鼠舌下神经损伤后神经修复再生的作用。方法60只SD大鼠随机分为正常对照组（NC组）、实验对照组（NS组）和NGF治疗组（NGF组）,动物存活时间分别为1、3、5、7和14 d。分别于各时间点取脑干做免疫组化测定及Nissl染色,取神经干做透射电镜观察。结果舌下神经压榨损伤后,舌下神经核内磷酸化p38MAPK免疫阳性神经元数目和染色深度均增加（P<0.05）。NGF干预后舌下神经核内磷酸化p38MAPK免疫阳性神经元数目和染色深度均明显减少（P<0.05）。Nissl染色显示,术后7、14 d NGF组损伤侧舌下神经核内运动神经元存活率明显高于NS组。透射电镜观察NGF组神经干形态优于NS组。结论大鼠舌下神经压榨损伤后受损神经元p38MAPK的活性增强;外源性NGF能抑制大鼠舌下神经压榨损伤引起的舌下神经核运动神经元p38MAPK的激活;大鼠舌下神经压榨损伤后外源性NGF具有保护受损的舌下神经元及促进神经再生的作用。     

Degeneration and regeneration of motor and sensory nerves: a stereological study of crush lesions in rat facial and mental nerves

The aim of this study was to evaluate the degeneration and regeneration of a sensory nerve and a motor nerve at the histological level after a crush injury. Twenty-five female Wistar rats had their mental nerve and the buccal branch of their facial nerve compressed unilaterally against a glass rod for 30 s. Specimens of the compressed nerves and the corresponding control nerves were dissected at 3, 7, and 19 days after surgery. Nerve cross-sections were stained with osmium tetroxide and toluidine blue and analysed using two-dimensional stereology. We found differences between the two nerves both in the normal anatomy and in the regenerative pattern. The mental nerve had a larger cross-sectional area including all tissue components. The mental nerve had a larger volume fraction of myelinated axons and a correspondingly smaller volume fraction of endoneurium. No differences were observed in the degenerative pattern; however, at day 19 the buccal branch had regenerated to the normal number of axons, whereas the mental nerve had only regained 50% of the normal number of axons. We conclude that the regenerative process is faster and/or more complete in the facial nerve (motor function) than it is in the mental nerve (somatosensory function).     

Sciatic nerve regeneration induced by transplantation of in vitro bone marrow stromal cells into an inside-out artery graft in rat

Traumatic injury to peripheral nerves results in considerable motor and sensory disability. Several research groups have tried to improve the regeneration of traumatized nerves by invention of favorable microsurgery. Effect of undifferentiated bone marrow stromal cells (BMSCs) combined with artery graft on peripheral nerve regeneration was studied using a rat sciatic nerve regeneration model. A 10-mm sciatic nerve defect was bridged using an artery graft (IOAG) filled with undifferentiated BMSCs (2 × 10⁷ cells/mL). In control group, the graft was filled with phosphated buffer saline alone. The regenerated fibers were studied 4, 8 and 12 weeks after surgery. Assessment of nerve regeneration was based on behavioral, functional (Walking Track Analysis), electrophysiological, histomorphometric and immuohistochemical (Schwann cell detection by S-100 expression) criteria. The behavioral, functional and electrophysiological studies confirmed significant recovery of regenerated axons in IOAG/BMSC group (P < 0.05). Quantitative morphometric analyses of regenerated fibers showed the number and diameter of myelinated fibers in IOAG/BMSC group were significantly higher than in the control group (P < 0.05). This demonstrates the potential of using undifferentiated BMSCs combined with artery graft in peripheral nerve regeneration without limitations of donor-site morbidity associated with isolation of Schwann cells. It is also cost saving due to reduction in interval from tissue collection until cell injection, simplicity of laboratory procedures compared to differentiated BMSCs and may have clinical implications for the surgical management of patients after facial nerve transection.     

Facial nerve repair with epineural suture and anastomosis using fibrin adhesive: An experimental study in the rabbit

PURPOSE: An experimental model in rabbits was used to compare epineural suturing and fibrin adhesive anastomosis for facial nerve repair. MATERIALS AND METHODS: Thirty-four facial nerves from 17 rabbits were isolated, transected, and anastomosed, with an evaluation of their electrophysiologic and histologic parameters. The rabbits were divided into 2 groups of 5 and 12 animals, respectively: a 10-mm defect was made in the right facial nerve in the first group, with transection and epineural suturing of the left nerve, followed by death after 120 days. This was the control-versus-epineural suture group. In the second group, the right facial nerve was transected and subjected to epineural suturing, while the left nerve was transected and anastomosed using fibrin adhesive. The rabbits were killed 15, 30, 60, and 120 days after the microsurgical procedure. This was the epineural suture-versus-fibrin adhesive group. RESULTS: From day 30, the number of regenerated axons increased with time in the epineural suture and fibrin adhesive anastomotic specimens. Epineural suture showed more regenerated axons and a faster linear rate of regeneration than anastomosis with fibrin adhesive. The reduction in conduction velocity decreased significantly with time with the same linear pattern for both suture techniques. CONCLUSIONS: Epineural suturing offered superior performance versus anastomosis with fibrin adhesive in terms of axon count but not in decrease in conduction velocity.     

应用纤维蛋白胶和医用OB胶修复兔面神经损伤的实验研究

目的:探讨用纤维蛋白胶或医用OB胶修复兔面神经的损伤效果。方法:手术制作实验用健康30只新西兰大耳白兔右侧面神经下颊支损伤模型,随机分成3组,分别为显微外科吻合组(Ⅰ组)、纤维蛋白胶粘合组(Ⅱ组)、医用OB胶粘合组(Ⅲ组),分别进行修复。术后16周进行大体观察、神经电生理检测、组织学观察、图像分析,评价神经再生恢复情况。结果:16周时肉眼观察3个组吻合口处均见神经再生,可抵抗一定拉力,Ⅰ组和Ⅲ组修复神经的周围软组织粘连较Ⅱ组严重;与Ⅰ组相比,Ⅱ组轴突再生率和再生轴突恢复比均有提高。结论:纤维蛋白胶和医用OB胶均有较好的生物相容性,可修复神经损伤,纤维蛋白胶对神经损伤的修复效果更佳。     

p75NTR对小鼠面神经损伤轴突再生影响的实验研究

目的:探讨p75神经营养蛋白受体(p75 neurotrophin receptor,p75NTR)在面神经损伤再生修复中的作用。方法:p75NTR基因敲除小鼠和野生型小鼠的面神经总干损伤后第4天,在损伤的近中侧注射霍乱毒素B(choleratoxin B,CTB)进行示踪,对再生神经纤维进行免疫组化染色,然后计数进行统计分析。结果:p75NTR基因敲除小鼠再生的神经纤维,明显较野生型小鼠的短,差异有显著性(P<0.01)。结论:p75NTR可以增强面神经的再生。     

静磁场对牙周炎大鼠牙周膜组织中骨形成蛋白-2影响的实验研究

目的　观察静磁场对实验性牙周炎大鼠牙周膜组织中骨形成蛋白-2(BMP-2)表达的影响。方法　36只大 鼠牙周结扎、高糖喂食5周,确定形成牙周炎模型后,分为2组,每组18只。实验组在大鼠双侧颊部皮下组织区埋 入表面磁场强度为0.12 T的磁体,实验对照组埋入不充磁的磁体。2组大鼠分别于术后的第2、4、7天处死,切取牙 周炎患牙及其周围牙周组织,采用SABC免疫组化方法检测病变区牙周膜组织中BMP-2的变化。同时设正常对照 组。结果　静磁场作用后,牙周膜组织中BMP-2表达增多,第4天和第7天时与实验对照组间存在显著性差异 (P<0.05)。结论　静磁场能够促进牙周炎牙周膜细胞分泌BMP-2,从而参与牙周组织的修复与重建。     

常规静脉与内翻静脉移植修复兔面神经缺损的对比研究

目的:比较自体常规静脉与内翻静脉移植修复面神经缺损的效果。方法:选用48只新西兰大白兔为实验对象,随机分为A,B两组。节段性切除所有动物左侧面神经颊支,造成10 mm的缺损。切取同侧的颈外静脉15mm,A组动物用常规静脉而B组动物用内翻静脉即刻修复面神经缺损。在手术后4,8与16周分别处死8只动物,取神经标本行定量组织学与透射电镜观察神经再生情况。结果:在术后4~8周,自体内翻静脉移植组修复面神经的有髓神经纤维的再生多于常规静脉移植组。但在16周时两组无明显差异。结论:自体静脉可以为面神经节段性缺损提供修复与再生的管道;内翻静脉相对于常规静脉可能产生更快的神经再生与修复。     

An experimental study on regeneration of the inferior alveolar nerve after lyophilized nerve homografting in the rabbit

This study was designed to evaluate the differences between the regenerative process in cases of autogenous nerve grafting and lyophilized homologous nerve grafting. Rabbit inferior alveolar nerves (10 mm lengths) were resected and replaced with lyophilized homologous segments from the sciatic nerve. On the opposite side, the resected nerves were autogenously grafted. The experimental subjects were divided into autogenous nerve-graft and the lyophilized nerve-graft groups. Results. 1. Regenerating axons appeared in the autogenous-graft group 2 weeks after the operation and 4 weeks after the operation in the homografted lyophilized group. The difference in regeneration between the 2 groups was significant. 2. Regenerating axons in the autogenously grafted nerves made contact with remaining Schwann cells and endneural tubes. Axons in the homografted lyophilized nerves invaded along newly infiltrated Schwann cells and empty tube skeletal structures. The number of regenerating axons from outside the skeletal structure was greater than the number of regenerating axons from inside the skeletal structure. 3. In the case of autogenous grafting, nerve fibers of diameters greater than 3 microns increased 66.7% after 24 weeks; the corresponding figure for homografted lyophilized nerves was 48.4%. 4. In instances of autogenous grafting, 16 weeks after surgery, the ratio of distal proximal myelinated nerve fibers had grown. In cases of homografted lyophilized nerves, this tendency to increase continued until the twenty-fourth postsurgical week. 5. In both groups, it remained possible to record nerve action potentials 12 weeks after surgery. The sensory nerve conduction velocity of autogenously grafted nerves increased gradually to approach control values 24 weeks after surgery. That of homografted lyophilized nerves recovered more slowly. 6. Increases in number of nerve fibers with a diameter of more than 3 microns were proportional to the rate at which sensory nerve conduction velocity recovered.     

静磁场对大鼠牙周膜组织中骨形成蛋白-2表达的影响

目的:观察静磁场对大鼠牙周膜组织中骨形成蛋白(BMP-2)的影响,探讨磁场对牙周膜组织的作用机制。方法:35只健康雌性Wistet大鼠,随机分为对照组、实验对照组和实验组。在实验对照组和实验组的大鼠双侧颊部,分别埋入未充磁的磁体和表面磁场强度为0.12 T的磁体,于术后第2、4、7天,切取双侧上颌磨牙及其周围牙周组织。采用免疫组化方法,检测局部牙周膜组织中BMP-2的变化。结果:牙周膜成纤维细胞、成骨细胞、成牙骨质细胞及胶原纤维中均可见BMP-2阳性染色。实验对照组与正常组的牙周膜BMP染色相似;静磁场作用后,实验组牙周膜组织中:BMP-2增多。统计学分析表明,在加磁场后的第4、7天,实验组与各对照组间存在显著差异,P<0.05。结论:静磁场可促进牙周膜细胞分泌BMP-2,推测静磁场对牙槽骨的生长具有一定的修复作用。     

面神经损伤后神经元中BCL-2、P53表达的实验研究

目的研究大鼠面神经总干压榨伤及切断伤后,BCL-2、P53在其神经元中的表达。方法将35只SD大鼠随机分为三组：组I右侧面神经总干压榨伤,组II为同体左侧面神经总干切断伤,组Ⅲ为正常对照侧。用HE染色的方法观测术后各期面神经元的形态学变化,用二步免疫组化法检测面神经元内BCL-2、P53蛋白的表达。结果面神经总干压榨伤后,其神经元未发生死亡,而总干切断伤会引起神经元死亡,面神经干切断1w后BCL-2、P53蛋白表达开始增强,3w时达到高峰,且切断后神经元数与BCL-2,P53的表达有明显相关性。结论BCL-2、P53蛋白参与面神经总干切断后诱导神经元凋亡过程的调控,BCL-2,P53的表达变化决定面神经死亡。