感觉神经植入术后SP类阳性纤维再生的形态学研究

目的 观察猴失神经皮肤内植入感觉神经后,ＳＰ（ｓｕｂｓｔａｎｃｅ－Ｐ）类阳性纤维的再生情况。方法 以猴手制成失神经模型,在神经植入术后１、３、５、８、１２个月后取材,进行ＳＰ抗体的免疫组化染色。结果 于术后３个月,在真皮深层出现ＳＰ类阳性纤维。术后５个月真表皮交界处出现ＳＰ类阳性纤维及末梢,在乳头层有ＳＰ染色阳性触觉小体。随时间延长,再生程度逐渐恢复。结论 感觉神经植入失神经皮肤后可以再生出ＳＰ类     

失神经皮肤植入神经后新生轴突再生的机制探讨

目的观察感觉神经植入术后皮肤内S-100蛋白染色的变化情况.方法利用已建立的猴失神经皮肤手指模型,再神经植入后1、3、5、8和12个月对手指指腹皮肤进行免疫组织化学染色,光镜下观察结果.结果正常皮肤中,有少量S-100蛋白染色阳性的神经纤维和感觉小体,感觉神经植入后,阳性标记物明显增强,尤其在神经植入后3～5个月时,免疫反应阳性的增加显著,随后略有减弱,12个月后接近正常皮肤的染色情况.结论植入的神经恢复了感觉神经结构和功能的完整性,可以使感觉小体获得神经再支配.S-100蛋白在维持神经正常的功能方面发挥重要的作用,神经损伤后雪旺氏细胞对神经的再生影响与S-100蛋白密切相关.     

猴移植皮肤感觉再生的实验研究

目的 移植皮肤的感觉再生缺乏深入的实验研究。通过恒河猴额部与手指掌侧无毛皮肤的相互移植，观察无毛皮肤移植后感觉小体再生过程与再生类别。方法 实验用恒河猴2只，随机抽取前肢指4个，将指腹与额、臀部的无毛皮对换移植，在3，9个月时切取标本进行抗神经丝免疫组化与电镜观察。结果 移植皮肤在3个月时神经未梢与触觉小体开始不典型再生；9个月的皮肤内已有典型的再生触觉小体，而上皮细胞—轴突复合体内有神经长入；移植皮肤内有较多的再生触觉小体，上皮细胞—轴突复合体有完整的再生结构。结论 移植皮肤内存在感觉小体的再生，这些结构与移植后的功能需要有关。     

猴移植皮肤感觉再生的实验研究

目的移植皮肤的感觉再生缺乏深入的实验研究。通过恒河猴额部与手指掌侧无毛皮肤的相互移植,观察无毛皮肤移植后感觉小体再生过程与再生类别。方法实验用恒河猴2只,随机抽取前肢指4个,将指腹与额、臀部的无毛皮对换移植,在3,9个月时切取标本进行抗神经丝免疫组化与电镜观察。结果移植皮肤在3个月时神经末梢与触觉小体开始不典型再生;9个月的皮肤内已有典型的再生触觉小体,而上皮细胞—轴突复合体内有神经长入;移植皮肤内有较多的再生触觉小体,上皮细胞—轴突复合体有完整的再生结构。结论移植皮肤内存在感觉小体的再生,这些结构与移植后的功能需要有关。     

端侧吻合移植神经重建皮瓣感觉的形态观察

目的:探讨感觉神经端侧吻合重建皮瓣感觉的可能性。方法 :用新西兰兔25只 ,将兔的一条耳大神经作为供神经 ,在另侧耳取耳大神经移植体(受神经) ,与供神经作端侧吻合后埋入失神经皮瓣 ,按神经移植体埋入皮瓣后时间分为1、2、4个月3个实验组 ,另设正常皮肤组和未植神经对照组 ,每组动物5只。用抗神经丝抗体免疫组化技术观察神经再生形态和分布 ;用电镜观察再生神经的超微结构。结果 :(1)感觉神经端侧吻合后1个月 ,供神经的轴突即可长入神经移植体(受神经) ,随时间延长 ,再生轴突数量逐渐增多。(2)再生神经纤维的超微结构基本正常。结论 :兔耳大神经端侧吻合植入失神经皮瓣后 ,供神经的轴突能长入神经移植体 ,并最终形成具有功能的感觉未梢。     

猴指、趾腹内触觉小体的形态学比较并1例临床报告

目的观察猴指、趾腹内触觉小体的特征,为足趾作为供区修复临床指尖缺损提供理论根据。方法切取猴指和趾腹部的全层皮肤标本,进行免疫组化S-100蛋白染色,光镜观察结合图像分析检测触觉小体的形态和数量。临床对急诊手外伤指腹缺损的患者,选取其脚趾腹侧全厚皮,植于创面,半年后复诊。结果猴指、趾腹内真皮乳头含有大量的触觉小体,其数量分别是(0.93±0.4)/mm和(0.92±0.4)/mm,小体的大小分别是(20～136±2)μm和(18～141±2)μm。在形态、数目和大小上,两种皮肤类型中的触觉小体差异无显著性意义(P>0.05)。临床上植于手指尖腹部的来自自体趾腹的全厚皮成活良好。数月后复诊,感觉功能恢复较佳。结论指尖的皮肤与脚趾主要的感觉小体结构十分近似,足趾可作为指尖皮肤缺损修复时一个理想的皮肤供区。     

周围神经损伤期修复后感觉终器的重建

通过观察灵长类动物指神经切断后感觉终器的蜕变和不同时间修复神经后感觉终器的重建过程,发现触觉小体失神经支配30周基本蜕变消失;在触觉小体消失前修复神经,再生神经纤维可以与残留的小体重建连接。环层小体蜕变缓慢,修复神经后可以恢复基本结构。提示晚期修复周围神经对重建感觉功能有重要的价值。     

周围神经损伤期修复后感觉终器的重建

通过观察灵长类动物指神经切断后感觉终器的蜕变和不同时间修复神经后感觉终器的重建过程，发现触觉小体失神经支配30周基本蜕变消失；在触觉小体消失前修复神经，再生神经纤维可以与残留的小体重建连接。环层小体蜕变缓慢，修复神经后可以恢复基本结构。提示晚期修复周围神经对重建感觉功能有重要的价值。     

猴指、趾腹内触觉小体的形态学比较并1例临床分析

目的 观察猴指、趾腹内触觉小体的特征，为足趾作为供区修复临床指尖缺损提供理论根据。方法 切取猴指和趾腹部的全层皮肤标本，进行免疫组化S－100蛋白染色，光镜观察结合图像分析检测触觉小体的形态和数量。临床对急诊手外伤指腹缺损的患者，选取其脚趾腹侧全厚皮，植于创面，半年后复诊。结果 猴指、趾腹内真皮乳头含有大量的触觉小体，其数量分别是（0．93&;#177;0．04）/mm和（0．92&;#177;0．4）mm，小体的大小分别是（20－136&;#177;2）μm和（18－141&;#177;2）μm。在形态、数目和大小上，两种皮肤类型中的触觉小体差异无显著性意义（P＞0．05）。临床上植于手指尖腹部的来自自体趾腹的全厚皮成活良好。数月后复诊，感觉功能恢复较佳。结论 指尖的皮肤与脚趾主要的感觉小体结构十分近似，足趾可作为指尖皮肤缺损修复时一个理想的皮肤供区。     

咀嚼肌瓣面神经再支配的实验研究

目的 :探讨失神经支配的咬肌瓣获得面神经再支配后的结构特性变化。方法 :取 2 0只新西兰大白兔 ,分为两组 (每组 10只 ) :A组行面神经 -咬肌神经端端移植吻合 ;B组行面神经咬肌内移植植入。术后分别在第1、3、6个月进行大体观察及肌湿重测定、电生理检查、酶组织化学检查及超微结构观察。结果 :失神经咬肌可重获面神经再支配 ,并在面神经支配下行使收缩功能 ,肌纤维的组化型别发生改变 ,从而使咬肌的肌纤维类似于表情肌。两种神经支配方法在术后 3个月MCV的恢复均有显著差异 (P <0 0 1) ;术后 6个月 ,两者无显著差异 (P >0 0 5 )。结论 :两种方法结果相似 ,均能使移植肌重获神经支配 ,恢复收缩功能。但在一期手术时 ,神经肌内植入方法简单 ,效果较移植吻合法相同 ,对临床手术治疗面瘫有一定的借鉴作用     

端侧神经吻合后降钙素基因相关肽在背根神经节及神经纤维中的表达

目的研究端侧神经吻合后，降钙素基因相关肽(CGRP)阳性纤维的再生情况。方法利用兔耳大神经端侧吻合模型，以免疫组化染色技术对供受神经节和神经纤维染色。结果供神经侧、术后的C     

Human dermal microvascular endothelial cells produce nerve growth factor: implications for wound repair

Following cutaneous injury, sensory nerves regenerate into the dermis and epidermis. Tissues that are innervated by sensory nerves synthesize neurotrophins such as nerve growth factor (NGF). The close anatomic proximity of nerves and capillaries throughout the skin suggests that mutual regulation may exist between nerve fibers and microvascular endothelial cells (MECs) during wound repair. Release of the neuropeptide substance P by sensory nerves induces endothelial cell rounding, capillary leak, and cytokine upregulation. We propose that dermal endothelial cells produce neurotrophins required for nerve fiber maintenance and regeneration. In this study, we demonstrate that substance P stimulates NGF messenger RNA expression by cultured human dermal MECs. Likewise, enzyme-linked immunosorbant assay demonstrated that conditioned medium from cultured dermal MECs contains NGF. NGF bioactivity in the supemates was verified by conditioned medium-induced clonal rat pheochromocytoma (PC-12) cell differentiation. This activity was inhibited by anti-NGF antibodies. Therefore, we have demonstrated that substance P, an inflammatory neuropeptide released by sensory nerve fibers, induces endothelial cells to produce NGF. Our data suggest that MECs may be unrecognized contributors to nerve regeneration after cutaneous injury.     

感觉神经端侧吻合后再生纤维的功能

目的:应用两种电生理技术,评价感觉神经端侧吻合后再生神经的功能。方法:取兔(新西兰兔15只,雌雄不拘,随机分为实验组、对照组和正常组,每组5只)耳大神经移植体作为受神经,与对侧耳大神经端侧吻合并植入皮瓣。用神经单纤维放电引导电生理技术检测皮瓣内再生放电纤维数量、分布、感觉类型。同时以免(新西兰兔16只,雌雄不拘,随机分为10,20,30周实验组和正常对照组,每组4只)2条耳大神经作端侧吻合模型,用RM-6280多道智能生理记录及分析处理系统测定再生纤维动作电位幅值恢复率和神经传导速度。结果:植入皮瓣的受神经在术后4个月可再生触、压、痛、温冷觉末梢,使皮瓣初步建立神经再支配。受神经内再生纤维的动作电位幅值恢复率10,20,30周时分别为(53.0±3.7)%,(66.8±5.5)%,(88.8±2.3)%;神经传导速度10,20,30周时分别为(42.4±1.6),(55.6±1.2),(57.2±1.6)m/s,随时间延长逐步增加。术后30周受神经近端再生纤维幅值恢复率和传导速度分别达到正常的88.8%和94.38%。结论:感觉神经端侧吻合后能再生有功能的神经纤维,再生速度稍慢。     

A comparison of peripheral nerve repair using an absorbable tubulization device and conventional suture in primates.

Median nerve regeneration was studied in 30 adult primates after repair by microsurgical suture or tubulization with a nonwoven, bioabsorbable, polyglycolic acid device. The two methods were compared electrophysiologically and histologically 6 and 12 months after repair. The electrophysiology included recording of electrically evoked compound action potentials and subsequent determination of threshold, conduction velocity, amplitude, and area above the baseline for each component. Measurements were obtained before nerve transection and at the time of biopsy by stimulating both proximal and distal to the transection site. Analysis of all electrophysiological parameters revealed no statistically significant differences (p less than 0.05) between the two repair techniques. Histopathology included examination of cross sections proximal and distal to the repair sites and longitudinal sections through the coaptation site. End organs (Meissner's and Pacinian corpuscles and muscle) were sectioned to determine the degree of reinnervation. No significant differences between the repair techniques were observed by histological analysis of these sections. These evaluations indicated that the tubulization repair technique produced results comparable to that of the suture technique.     

Immunolocalization of SNS/PN3 and NaN/SNS2 sodium channels in human pain states

The tetrodotoxin-resistant (TTX-R) voltage-gated sodium channel SNS/PN3 and the newly discovered NaN/SNS2 are expressed in sensory neurones, particularly in nociceptors. Using specific antibodies, we have studied, for the first time in humans, the presence of SNS/PN3 and NaN/SNS2 in peripheral nerves, including tissues from patients with chronic neurogenic pain. In brachial plexus injury patients, there was an acute decrease of SNS/PN3- and NaN/SNS2-like immunoreactivity in sensory cell bodies of cervical dorsal root ganglia (DRG) whose central axons had been avulsed from spinal cord, with gradual return of the immunoreactivity to control levels over months. In contrast, there was increased intensity of immunoreactivity to both channels in some peripheral nerve fibers just proximal to the site of injury in brachial plexus trunks, and in neuromas. These findings suggest that the expression of these sodium channels in neuronal cell bodies is reduced after spinal cord root avulsion injury in man, but that pre-synthesized channel proteins may undergo translocation with accumulation at sites of nerve injury, as in animal models of peripheral axotomy. The latter may contribute to positive symptoms, as our patients all showed a positive Tinel's sign. Nerve terminals in distal limb neuromas and skin from patients with chronic local hyperalgesia and allodynia all showed marked increases of SNS/PN3-immunoreactive fibers, but little or no NaN/SNS2-immunoreactivity, suggesting that the former may be related to the persistent hypersensitive state. Axonal immunoreactivity to both channels was similar to control nerves in sural nerve biopsies in a selection of neuropathies, irrespective of nerve inflammation, demyelination or spontaneous pain, including a patient with congenital insensitivity to pain. Our studies suggest that the best target for SNS/PN3 blocking agents is likely to be chronic local hypersensitivity.     

Immunohistochemical localization of histamine H3 receptors in rodent skin, dorsal root ganglia, superior cervical ganglia, and spinal cord: potential antinociceptive targets

Activation of histamine H3 receptors (H3Rs) reduces inflammation and nociception, but the existence of H3Rs on peripheral innervation has never been demonstrated. Here we use antibodies to locate H3Rs in whisker pads, hairy and glabrous hind paw skin, dorsal root ganglia (DRGs), and spinal cords of rats, wild type mice, and H3R knockout (H3KO) mice. Although H3Rs have been hypothesized to be on C and sympathetic fibers, H3R-like immunoreactivity (H3R-LI) was only detected on presumptive periarterial A delta fibers and on A beta fibers that terminated in Meissner's corpuscles and as lanceolate endings around hair follicles. The H3R-positive periarterial fibers were thin-caliber and coexpressed immunoreactivity for calcitonin gene-related peptide (CGRP), substance P, acid sensing ion channel 3, and 200 kDa neurofilament protein (NF). H3R-LI was also detected on epidermal keratinocytes and Merkel cells, but not on Merkel endings, C fibers, any other A delta fibers, or sympathetic fibers. In DRGs, H3R-LI was preponderantly on medium to large neurons coexpressing NF-LI and mostly CGRP-LI. In dorsal horn, CGRP-positive fibers with and without H3R-LI ramified extensively in lamina II; many of the former formed a plexus in lamina V. Low levels of H3R-LI were also present on A beta fibers penetrating superficial and into deeper laminae. The distribution of H3R-LI was similar in rats and wild type mice, but was eliminated or strongly reduced in A delta fibers and A beta fibers, respectively, in H3KO mice. Taken with recently published behavioral results, the present findings suggest that periarterial, peptidergic, H3R-containing A delta fibers may be sources of high threshold mechanical nociception.