人参皂甙Rb1对玻璃化保存坐骨神经异体移植后神经再生的影响

[目的]探讨人参皂甙Rb1(Ginsenoside Rb1,G-Rb1)对大鼠坐骨神经玻璃化保存及异体移植后神经再生的影响.[方法] Wistar大鼠坐骨神经在0、50、100、200 μg·L-1 G-Rb1玻璃化液(A、B、C、D组)中,-20℃保存4周,透射电镜观察超微结构,TUNEL法检测细胞凋亡.用玻璃化保存后的坐骨神经修复对应组SD大鼠(A’、B’、C’、D’组)坐骨神经10 mm缺损.术后4、8、14周坐骨神经功能指数观察,术后16周电生理检测、再生神经组织学观察及靶肌肉运动终板观察.[结果]坐骨神经玻璃化保存4周后,A组神经脱髓鞘严重,施万细胞质膜和基底膜破坏,B、C、D组髓鞘轻微变性,施万细胞质膜和基底膜保持完整;细胞凋亡B、C、D组轻于A组,C、D组轻于B组(P＜0.05),C、D组间差异无统计学意义(P＞0.05).术后不同时间坐骨神经功能指数,16周运动神经传导速度、动作电位潜伏期及波幅,运动终板数量、面积、着色,B’、C’、D’组与A’组间,C’、D’组与B’组间,差异均有统计学意义(P＜0.05),而C’、D’组间差异无统计学意义(P＞0.05).透射电镜显示,A’、B’组再生有髓神经纤维较少、髓鞘较薄,结缔组织增生明显,C’、D’组再生有髓神经纤维较多、髓鞘厚,无明显结缔组织增生.[结论] G-Rb1对玻璃化保存大鼠坐骨神经具有保护作用,并能促进异体移植后神经再生.     

供体神经雷公藤预处理对异体移植后神经再生的影响

[目的]探讨雷公藤多甙(雷公藤提取物)或MEM预处理的供体坐骨神经对异体周围神经缺损修复的影响.[方法]用新鲜异体坐骨神经移植(A组)或雷公藤多甙(B、C组)/MEM(D、E组)预处理的Wistar大鼠坐骨神经,桥接SD大鼠10 mm坐骨神经缺损,术后以雷公藤多甙治疗5周:A、C、E组5 mg/(kg·d),B、D组2.5 mg/(kg·d).术后2周观察移植物炎症反应情况,12周电生理检测和组织学观察神经再生,16周观察靶肌肉运动终板.[结果]术后早期炎症反应D组比其它组严重;运动神经传导速度、动作电位潜伏期,再生有髓神经纤维数量和轴突直径、髓鞘厚度,C组优于A、B、E组(P<0.05),A、B、E组则优于D组(P<0.05);运动终板染色着色和数量,D组明显比其它组差.[结论]供体神经经雷公藤多甙预处理可能降低了神经组织免疫原性,异体移植后能促进神经再生,减少移植后受体免疫抑制剂用量.     

经雷公藤预处理大鼠异体神经移植后早期组织形态及免疫学观察

目的 观察经雷公藤预处理大鼠异体神经移植后髓鞘损伤程度及急性期免疫排斥反应,探讨雷公藤早期免疫抑制作用及合适用药浓度. 方法取60只3月龄雄性SD大鼠制备右侧坐骨神经干缺损模型,随机分为A、B、C、D、E组5组(n=12).取18只3月龄雄性Wistar大鼠,切取双侧坐骨神经干约15 mm,置入含200、400、800 mg/L雷公藤多甙细胞保存液(各浓度组浸泡12条神经),4℃下浸泡24 h,作为A、B、C组神经修复供体,修复神经缺损;另取6只3月龄Wistar大鼠,切取12条新鲜坐骨神经桥接于D组神经缺损处;E组将切下的自体坐骨神经立即行原位缝合.术后不同时间对移植神经行大体、光镜、电镜观察,检测髓鞘碱性蛋白(myelin basic protein,MBP)含量变化及免疫组织化学分析移植物CD4 、CD8 T细胞入侵情况. 结果 术后1周,A、B、C组神经纤维形态及结构较完整,炎性细胞浸润程度较D组轻;术后1、2、4周,A、B、C组组织形态学观察结果 相似,移植神经片段外形及结构清晰,与周围结缔组织粘连均较D组轻;术后48h及1、2、4周,各组均有不同程度髓鞘损伤,各时间点坐骨神经MBP含量B组最接近E组,两组差异无统计学意义(P＞0.05).术后1、4周,A、B、C组CD4 ,CD8 分子的IA值与D组比较,差异均有统计学意义(p＜0.05). 结论 雷公藤能有效降低异体神经移植术后早期急性排斥反应,对髓鞘发挥一定的保护作用.     

异体神经段皮下包埋对坐骨神经再生影响的研究

目的　探讨异体周围神经段皮下包埋对坐骨神经再生的影响。　方法　 Wistar大鼠 30只 ,雄性。 6只为供体 (C组 ) ,余随机分为两组。实验组 (A组 ) 12只 ,于右大腿后侧皮下行异体坐骨神经 (15 mm)包埋 ,2周后取出 ,修整为 10 mm的片段移植于左侧新鲜的坐骨神经缺损处 (10 m m)。对照组 (B组 ) 12只 ,于右腿相应部位皮肤切口直接缝合 ,左侧新鲜坐骨神经 (10 mm)原位吻合。术后 2、4、8和 14周行组织学观察 ,14周作电生理测定和电镜观察。　结果　术后 2周 ,A组炎性反应稍重于 B组 ;至 4周时两组的炎性反应程度相似 ,近端少许胶原纤维增生 ;8周时两组的炎性反应基本停止 ,胶原纤维增生稍明显 ;14周时两组神经外膜构成完整 ,束膜、内膜结构无明显差异。再生大量的有髓神经纤维及少量的无髓神经纤维。髓鞘结构完整。再生轴突数目、面积差异无统计学意义 ,束膜厚度、分布及范围相似。运动神经传导速度、峰值及潜伏期差异无统计学意义 (P>0 .0 5 )。　结论　皮下包埋的异体周围神经段虽有一定的炎性反应 ,但仍具有与自体神经移植相似的神经再生引导作用。     

不同角度修复大鼠坐骨神经损伤的组织学研究

目的观察比较不同角度吻合对大鼠坐骨神经损伤再生的促进作用。方法健康成年雄性SD大鼠72只,体重250～300 g,随机分为A、B、C、D 4组(n=18)。A、B、C、D组分别以30、45、60、90°切断大鼠右侧坐骨神经中段并吻合。术后1、2、3个月,分别行大体观察、腓肠肌湿重恢复率测量、神经电生理检查及组织学观测。结果术后3个月,腓肠肌湿重恢复率、坐骨神经运动传导速度和复合动作电位波幅、轴突直径、髓鞘厚度以及有髓神经纤维计数,A、B组间比较差异无统计学意义(P>0.05),但均明显优于C、D组,差异有统计学意义(P<0.01);C、D组间各指标比较差异无统计学意义(P>0.05)。结论小角度端端吻合修复神经有利于神经再生,30～45°吻合神经再生效果最佳。     

不同角度修复大鼠坐骨神经损伤的组织学研究

目的观察比较不同角度吻合对大鼠坐骨神经损伤再生的促进作用。方法健康成年雄性SD大鼠72只,体重250～300 g,随机分为A、B、C、D 4组(n=18)。A、B、C、D组分别以30、45、60、90°切断大鼠右侧坐骨神经中段并吻合。术后1、2、3个月,分别行大体观察、腓肠肌湿重恢复率测量、神经电生理检查及组织学观测。结果术后3个月,腓肠肌湿重恢复率、坐骨神经运动传导速度和复合动作电位波幅、轴突直径、髓鞘厚度以及有髓神经纤维计数,A、B组间比较差异无统计学意义(P>0.05),但均明显优于C、D组,差异有统计学意义(P<0.01);C、D组间各指标比较差异无统计学意义(P>0.05)。结论小角度端端吻合修复神经有利于神经再生,30～45°吻合神经再生效果最佳。     

腹腔注射ATP对大鼠坐骨神经再生影响的实验研究

目的 观察腹腔注射细胞外ATP对大鼠坐骨神经再生的影响。方法 健康雌性Wistar大鼠48只，随机分成两组。将两组大鼠左侧坐骨神经切断后立即行外膜吻合术。术后实验组腹腔注射ATP（2mg／kg）0．4ml，对照组注射生理盐水0．4ml。术后1周、4周和8周从每组随机取8只大鼠，检测每只大鼠双侧小腿三头肌湿重、术后1周时测神经纤维再生速度、术后4周时电镜检测髓鞘横截面积和髓鞘厚度。结果实验组与对照组相比，1周时神经再生速度快（P〈0．05）、4周时髓鞘横截面积大（P〈0．05）、髓鞘厚（P〈0．05），4周、8周时小腿三头肌湿重明显优于对照组（P〈0．05）。结论 腹腔注射细胞外ATP对大鼠神经再生和功能恢复具有较强促进作用。     

辐照和绿茶多酚处理同种异体神经移植体的实验研究

[目的]比较经绿茶多酚溶液及辐照预处理的同种异体神经修复大鼠坐骨神经缺损的效果.[方法] 48只成年雄性Wista大鼠,将坐骨神经在梨状肌孔下5 mm处切除1.0 cm,随机分为4组,每组12只,神经缺损分别用4种移植物桥接.A组:自体神经移植;B组:新鲜异体神经移植;C组:经辐照处理的异体神经移植;D组:绿茶多酚溶液保存的异体神经移植.术后6、12周通过大体、电生理学、组织学、透射电镜观察评价各组修复神经缺损的效果.[结果]A、D组间差异无统计学意义,A、D组的各项指标均优于B、C组.[结论]大鼠坐骨神经缺损模型中,绿茶多酚溶液保存的同种异体神经是良好的神经移植替代材料,移植后神经再生情况优于辐照预处理的异体神经.     

甲状腺激素人工神经桥接大鼠坐骨神经缺损的组织学观察

目的对甲状腺激素人工神经外消旋聚乳酸-三碘甲状腺素原氨酸[Poly(dextrogyr-levogyr)lactideacide-triiodothyronine,PDLLA-T3]桥接大鼠坐骨神经缺损的效果进行组织学评价。方法将90只SD大鼠左侧坐骨神经切断造成1cm缺损,随机分为3组,每组30只。A组:自体神经移植组;B组:PDLLA-T3组;C组:不含甲状腺激素人工神经外消旋聚乳酸(PDLLA)组;桥接坐骨神经缺损。D组:正常对照组(大鼠右侧正常坐骨神经)。于术后2周,1、2个月收集标本,行透射电镜、HE染色、Bielschowsky神经纤维银染及S-100免疫组织化学染色,观察再生神经的数量和质量,经图像处理后进行统计分析。结果术后2周:组织学观察显示B、C组材料尚未完全降解,透射电镜下神经的髓鞘厚度较薄,约0.5μm,A、B、C组间差异无统计学意义(P>0.05);1个月:组织学观察见A组再生神经纤维等组织通过远端吻合口,其间有新生的血管,B、C组材料未完全降解,S-100免疫组织化学及Bielschowsky神经纤维银染显示B组PDLLA-T3成功桥接神经缺损,缺损段有再生神经通过,再生神经髓鞘厚度1.81±0.19μm,优于A、C组,但差异无统计学意义(P>0.05);2个月:B、C组材料完全降解,B组S-100免疫组织化学染色示神经纤维数110.00±8.75,Bielschowsky神经纤维银染显示再生有髓神经纤维数77.00±6.33,两者均优于C组(P<0.05),且与A、D组比较差异有统计学意义(P<0.05);髓鞘厚度为2.15±0.27μm,优于C组(P<0.05),但小于A、D组(P<0.05)。结论PDL-LA-T3桥接大鼠坐骨神经缺损,再生神经纤维数量和质量较好,是一种有前途的组织工程人工神经。     

不同时段异体神经片段皮下包埋对周围神经再生影响的实验研究

目的 探讨异体神经片段经皮下包埋不同时段后对周围神经再生的影响。方法 Wistar大鼠55只，雌雄不限，随机分为5组，A、B、C组（实验组）和D组（对照组）每组各10只，E组（供体组）15只。E组动物在出骨盆口以远5mm处切断双侧坐骨神经，向远端游离约15mm，切断作为移植物。A、B、C组动物均行左侧大腿切口，皮下钝性分离，埋入供体神经片段。术后1周（A组）、2周（B组）、3周（C组）显露右侧坐骨神经，距骨盆出口约5mm处切断，向远端游离约10mm再切断，取出对侧包埋的神经片段，修剪远近端保留长度约10mm，移植于右侧神经缺损处。D组显露右侧坐骨神经后，在距骨盆出口约5mm处切断，向远端游离约10mm后再切断，原位缝合。术后2、4、6、8、10及12周监测坐骨神经功能指数（sciatic functional index，SFI），术后12周行电生理检查测试运动神经诱发电位的传导速度及潜伏期，组织学检测移植神经再生轴突数目和面积，以及移植神经的超微结构变化。结果术后各组SFI逐渐下降，12周时A组和D组的SFI最小，两组间差异无统计学意义，但分别与B组和C组比较差异有统计学意义（P〈0．05）。术后12周A组和D组再生大量有髓神经纤维及少量无髓神经纤维，再生神经的数量和结构与正常神经相似，图像分析显示两组间无明显差别，与B组和C组比较差异有统计学意义（P〈0．05）。A组和D组的运动神经传导速度及潜伏期结果无差异，优于B组和C组，且差异有统计学意义（P〈0．05）。结论 异体神经片断皮下包埋后有促进周围神经再生的作用，皮下包埋1周组促神经再生作用优于皮下包埋2、3周组。     

Quantification of nerve tension after nerve repair: correlations with nerve defects and nerve regeneration

This study tested the validity of a quantitative in vitro nerve-tension-measuring technique, by correlating the tension measurements with functional and morphologic assessments of nerve regeneration. Initially, harvested nerves were used in vitro to determine a K value for lateral displacement in this tissue. Next, this value was used to calculate the tension of nerve repair, following 0-, 3-, 6-, and 9-mm resections of nerves in groups of rats. After quantifying the nerve tensions following excision and repair, the authors determined a sciatic function index to evaluate functional recovery and axon diameter in the animals. Functional recovery was significantly impaired in animals with elevated measurable tension (9.04 +/- 0.74 g in a 6-mm defect, 27.76 +/- 8.86 g in a 9-mm defect), compared to animals with no or 3-mm excision and measured tension of 3.3 +/- 1.09 g or less. Increased tension was also associated with a significant decrease in axon diameter. This study succeeded, therefore, in quantitatively relating the elements of measured nerve tension, nerve gaps, functional nerve recovery, and morphologic regeneration. Quantification of nerve tension by lateral displacement in vivo offers a possible solution to clinical management of nerve gaps, when the choice between primary repair and nerve grafting is not a clear one.     

Cavernous nerve regeneration using acellular nerve grafts

INTRODUCTION: The restoration of erectile function following complete transection of nerve tissue during surgery remains challenging. Recently, graft procedures using sural nerve grafts during radical prostatectomy have had favorable outcomes, and this has rekindled interest in the applications of neural repair in a urologic setting. Although nerve repair using autologous donor graft is the gold standard of treatment currently, donor nerve availability and the associated donor site morbidity remain a problem. In this study, we investigated whether an "off-the-shelf" acellular nerve graft would serve as a viable substitute. We examined the capacity of acellular nerve scaffolds to facilitate the regeneration of cavernous nerve in a rodent model. MATERIALS AND METHODS: Acellular nerve matrices, processed from donor rat corporal nerves, were interposed across nerve gaps. A total of 80 adult male Sprague-Dawley rats were divided into four groups. A 0.5-cm segment of cavernosal nerve was excised bilaterally in three of the four groups. In the first group, acellular nerve segments were inserted bilaterally at the defect site. The second group underwent autologous genitofemoral nerve grafts at the same site, and the third group had no repair. The fourth group underwent a sham procedure. Serial cavernosal nerve function assessment was performed using electromyography (EMG) at 1 and 3 months following initial surgery. Histological and immunocytochemical analyses were performed to identify the extent of nerve regeneration. RESULTS: Animals implanted with acellular nerve grafts demonstrated a significant recovery in erectile function when compared with the group that received no repair, both at 1 and 3 months. EMG of the acellular nerve grafts demonstrated adequate intracavernosal pressures by 3 months (87.6% of the normal non-injured nerves). Histologically, the retrieved regenerated nerve grafts demonstrated the presence of host cell infiltration within the nerve sheaths. Immunohistochemically, antibodies specific to axons and Schwann cells demonstrated an increase in nerve regeneration across the grafts over time. No organized nerve regeneration was observed when the cavernous nerve was not repaired. CONCLUSION: These findings show that the use of nerve guidance channel systems allow for accelerated and precise cavernosal nerve regeneration. Acellular nerve grafts represent a viable alternative to fresh autologous grafts in a rodent model of erectile dysfunction.     

End-to-side nerve repair in peripheral nerve injury

In peripheral nerve injury, end-to-side neurorrhaphy has been reported as an alternative in cases that the proximal nerve stump is not accessible. Several hypotheses have been proposed to explain peripheral nerve regeneration after end-to-side neurorrhaphy. Recent evidence suggests that nerve regeneration occurs by collateral sprouting. Although a great number of humoral factors have been identified, molecular mechanism of nerve regeneration after end-to-side neurorrhaphy has not been completely clarified yet. The goal of this technique is to provide satisfactory functional recovery for the recipient nerve, without any deterioration of the donor nerve function. End-to-side technique has been investigated in detail in both experimental and clinical studies. Only a limited number of reported cases in clinical practice, until today, can reveal that end-to-side technique may become a viable means of repairing peripheral nerves in certain clinical situations.     

内脏神经-体神经端侧吻合后神经纤维再生研究

目的 观察大鼠内脏神经-体神经端侧吻合后神经纤维的再生.方法 24只成年SD大鼠随机分为实验组(n=12)和正常对照组(n=12),实验组大鼠通过内脏神经-体神经端侧吻合建立人工体神经-内脏神经反射弧6个月后,在吻合口近端和远端分别截取10 mm的供体神经(L4VR)和受体神经(L6VR),在L6VR延续的盆副交感神经(PPN)和阴部神经(PN)分别截取10 mm的神经.正常对照组大鼠分别取相应节段的L4VR、L6VR、PPN和PN神经.标本经石蜡包埋切片并行甲苯胺蓝染色,比较实验组和对照组大鼠L6VR、PPN、PN神经纤维数量.结果 实验组大鼠横断面可见新生的有髓神经纤维,L4VR、L6VR、PPN和PN的神经纤维数量分别为1602.2±75.7、1037.9±123.6、817.0 ±52.2、510.4±29.1,吻合口远近端神经纤维通过率为64.8%,实验组和对照组大鼠相应的L6VR、PPN、PN神经纤维数目比率分别为70.2%、68.9%和62.2%.结论 大鼠内脏神经-体神经端侧吻合后体神经能够长入并替代内脏神经.     

End-to-side nerve graft for facial nerve reconstruction

Reconstruction of multiple branches of the facial nerve by sural nerve graft using end-to-side nerve suture was performed successfully on a patient with advanced parotid tumor. In this technique, one end of the grafted nerve is sutured with the stump of the facial nerve trunk in an end-to-end manner. Epineural windows are made on the nerve graft, and the distal stumps of the facial nerve branches (temporal, zygomatic, and buccal branches) are sutured with the graft in an end-to-side manner. Functional recovery of all branches and satisfactory facial expression were obtained within 2 years postoperatively. Axonal regeneration through the graft was confirmed by electrodiagnosis. Regeneration through the anastomosis at the stump of the facial nerve trunk using this technique is more efficient than conventional cable grafting, and the length of the nerve required is minimal. This technique may be a useful option for facial nerve reconstruction managing multiple branches.