SD大鼠马尾与骶神经根的解剖学观察

目的：为从马尾和骶神经根途径开展SD大鼠的神经泌尿学研究提供解剖依据。方法：对6只SD大鼠灌注后进行显微解剖，并对30只SD大鼠进行术中观察和测量，总结马尾、骶神经根的解剖特征。结果：SD大鼠的盆底器官主要由Sl～S4脊髓节段和神经根支配，脊髓圆锥延续较长，达L4椎体下缘，马尾神经亦较长，其前根1束较细，后根2束较粗，包于同一硬脊膜中，硬脊膜较厚而坚韧，脊髓神经前后根出硬脊膜后，有各自独立的硬脊膜囊包绕，直至椎管内硬脊膜囊两侧的后根神经节处，长约3个椎体高度。在4对骶神经根中，以Sl和S2较粗，S3、S4较细。盆神经副交感神经纤维主要来源于S2骶髓节段。结论：SD大鼠骶和尾神经根的解剖特征与人类不同。     

犬马尾与骶神经根的解剖学观察

目的：为从马尾和骶神经根途径开展犬的神经泌尿学研究提供解剖依据。方法：对3只犬灌后进行解剖,并对22只犬进行术中观察,总结马尾、骶神经根的解剖特征。结果：犬的盆底器官由S1～S2脊髓节段和神经根支配;脊髓圆锥延续较长,达L6椎体下缘,而马尾神经较短;髓神经前后根出硬膜后,有各自独立的硬膜囊包绕直至后根神经节处,长1～1.5cm。结论：犬马尾和骶神经根的解剖特征与人类不同。     

SD大鼠坐骨神经结构及其支配肌群的探讨

目的分析大鼠骶丛及坐骨神经的神经根组成，并分析各神经根对肌肉的具体支配功能。方法选用20只成年SD大鼠，雌雄不限，通过大体解剖了解坐骨神经的神经根组成：通过对L4—6神经根的刺激，分别检测股二头肌、小腿三头肌和胫前肌的肌电图，由此推断神经根对肌群的支配权重及定位关系。结果20只大鼠中，L4—6型有17只，L4—5型3只，两大类型又分两种亚型。通过肌电图分析，我们发现，L4．5是坐骨神经支配下肢肌肉的恒定支，L6神经根主要参与小腿三头肌的运动功能，但有两只大鼠，L6不参与对三组肌肉的支配。结论本实验基本明确了大鼠骶丛及坐骨神经的组成，利用肌电图的方法判定出大鼠下肢股二头肌、三头肌和胫前肌的神经根支配组成及权重，为建立大鼠骶丛撕脱模型奠定了坚实的基础。     

SD大鼠腰骶部脊神经前根显微外科解剖学观察

目的:为实验性高选择性腰骶神经前根小束切断术治疗圆锥上损伤的痉挛性膀胱提供可靠的神经根分束的形态学依据.方法:对6只雄性SD大鼠L1-S4节段的脊神经前根自然分束进行形态学观察和显微测量.结果:粗细不一的神经小束从脊髓发出,几个神经小束形成一个神经亚束.2～6个神经亚束构成一个神经束,或由神经小束直接形成神经束.腰骶部脊神经前根一般含有1股神经束,3～13支神经小束.L5-S2节段前根的小束数目在5支以上.每一前根内有一支神经小束较粗大,直径0.1～0.2 mm左右,其余较细小,最小可至0.01 mm左右,粗细程度存在较大差异.结论:实验性高选择性腰骶部前根神经小束切断术的分束可达到神经小束水平,以7～8支为宜.     

脊神经前根吻合重建脊髓损伤大鼠的股四头肌功能

背景：如何重建脊髓损伤肢体运动功能对截瘫患者具有重要的意义。 目的：探索利用脊髓损伤平面以上健存的脊神经前根与支配股四头肌的腰神经建立神经通路,恢复脊髓损伤后股四头肌的神经支配和肌收缩功能。 方法：对清洁级SD大鼠L₁神经根的前根与L3神经根的前根进行显微吻合。经一段时间(6个月)的轴突再生后,期望建立新的肌肉收缩功能。神经缝合后6个月,在破坏L₂ 脊髓节段前后,分别进行神经电生理检测,观察股四头肌神经支配情况。 结果与结论：在同侧L₂半切脊髓前后,电刺激移植神经干时可记录到股四头肌的收缩肌电图。在同侧L₂半切脊髓前后,电刺激L₁感觉根时可同样在股四头肌记录到肌电图。说明利用脊髓损伤平面以上健存的L₁神经根前根与L₃神经前根移植吻合能重建新的股四头肌神经支配反射通路,并使股四头肌低级反射中枢上移。     

腰骶部脊神经前后根会合段与椎板关系的解剖观察及临床意义

腰骶段选择性脊神经后根切断术，是在腰2～骶。每根脊神经前后根会合段解剖、分离后根，选择性的神经束切断：笔在足月婴儿尸解的基础上，通过骶椎板单开门切开显露选择性神经根切断术中解剖观察；对腰2-骶1脊神经前后根会合段的距离进行测量，对每条脊神经前后根会合段与相应椎板的关系，进行了临床解剖学观察。目的是为了保护脊柱稳定性采用椎板节段开窗施行选择性神经后根切断手术提供进一步的解创学资料。     

腰神经根管的解剖及临床意义

在60具成人标本上解剖观察了腰神经根管的构成及其与腰神经根的关系.上位腰神经(L1—3)根管分为椎管内段和椎间孔段,皆毗邻骨性结构.下位腰神经(L4—S1)根管分为侧隐窝段和椎间孔段,在侧隐窝段的上份,神经根前邻椎间盘,后邻黄韧带及椎间关节,周围间隙小,病变时易受压迫.     

用胸—骶神经根桥接治疗截瘫性大小便失禁的新术式

在20具成尸标本上解剖观测了第10胸神经～第3腰神经前、后根的长度、分束、各束直径以及它们的末端至第2～4骶神经根起始处的距离。设计了在椎管内用马尾神经桥接胸—骶神经根治疗截瘫性大、小便失禁的新术式,并就与该术式有关的应用解剖学问题进行了讨论。     

合并移行椎腰椎间盘突出症患者腰骶神经根支配区的变化

背景:腰骶移行椎是一种常见的先天脊柱畸形,国内外学者均有报道移行椎患者的腰骶神经根支配I区可能会发生改变,但并未系统阐述其支配区的变化以及该种改变对腰椎间盘突出症患者手术的指导意义。目的:探讨当存在腰骶移行椎时,腰骶神经根的运动和感觉支配区发生改变的可能性。方法:研究方案的实施符合滨州医学院附属医院对研究的相关伦理要求,参与试验的患病个体及其家属对试验过程完全知情同意。回顾分析321例单一节段腰椎间盘突出症行手术治疗患者的病历资料。其中38例(11.8%)存在腰骶移行椎,包括骶椎腰化26例、腰椎骶化12例。26例骶椎腰化患者中,23例为L5/S1(L6)椎间盘突出,压迫S1(L6)神经根。12例腰椎骶化患者中,8例为L3/4椎间盘突出,压迫L4神经根。在283例正常结构的患者中,138例患者L5/S1椎间盘突出压迫S1神经根,95例患者L4/L5椎间盘突出压迫L5神经根,47例患者L3/L4椎间盘突出压迫L4神经根。比较术前骶椎腰化患者S1神经根受压的症状、腰椎骶化患者L4神经根受压的症状与正常腰骶椎患者L4、L5或S1神经根受压的症状。结果与结论:(1)S1神经根受压所致运动功能减退的分布在骶椎腰化患者组和正常组之间差异有显著性意义(P<0.05);(2)L4神经根受压所致运动功能减退的分布在腰椎骶化患者组和正常组之间差异有显著性意义(P<0.05);(3)骶椎腰化患者S1神经根受压所致的运动功能减退与正常状态下L5神经根受压所致的运动功能减退相似;而腰椎骶化患者L4神经根受压所致的运动功能减退与正常状态下L5神经根受压所致的运动功能减退相似;皮肤感觉异常的分析也显示了相似的结果;(4)结果说明,腰骶神经根的功能在移行椎患者中发生改变,使得骶椎腰化患者的S1神经根起到L5神经根的通常功能(神经根功能上移),腰椎骶化患者的L4神经根起到L5神经根的通常功能(神经根功能下移)。     

利用膝腱反射重建膀胱功能的应用解剖研究

目的：为膝腱反射重建膀胱功能的手术时脊神经根和吻合平面的选择以及脊神经前根的定位提供解剖学依据。方法：在20具尸体标本上追踪股神经的脊神经根来源和相应的脊神经根的分布,同时观察硬膜内L2-4和S2-4脊神经前根排列的位置关系、相互重叠长度和横戴面积。结果：股神经主要由L3和L4脊神经根组成,L2脊神经根的贡献较小;L2和L3脊神经根中的大部分神经纤维贡献给股神经,其比例显著高于L4脊神经根。S2-4前根出脊髓的平面均高于或等于L2-4前根出硬膜的平面,L3和L4前根的横截面积均显著大于S2-4前根横截面积。结论：①利用膝腿反射得建膀胱功能时宜选用L3前根与S3或S4前根交叉吻合。②在L1-L2椎体平面,前后根的辨别和序列的确认较为容易,故吻合平面宜选择在脊髓圆锥处。     

Increased neuropeptide Y (NPY)-like immunoreactivity in rat sensory neurons following peripheral axotomy.

The effects of peripheral axotomy (sciatic nerve transection) on the presence and distribution of neuropeptide Y (NPY) in rat dorsal root ganglion (DRG) and spinal grey matter were examined using immunocytochemistry. In normal rats and on the sham-operated side of experimental rats, NPY-like immunoreactivity (NPYir) was observed in all laminae of the lumbar spinal cord, with an especially dense concentration of immunostained axons and axonal varicosities in laminae I-II of the dorsal horn. There was no detectable NPYir in L4-L5 DRG cells from normal rats or from the sham-operated side of experimental rats. At 14 days after axotomy, there was a large ipsilateral increase in the density of NPYir axons and varicosities in the lumbar spinal cord on the side of the nerve injury; this was especially apparent in laminae III-V. In the same rats, NPYir was observed in many small, medium, and large neurons in the L4-L5 DRGs on the side of the severed nerve.     

Role of different peripheral components in the expression of neuropathic pain syndrome

Peripheral nerve injury frequently leads to neuropathic pain like hyperalgesia, spontaneous pain, mechanical allodynia, thermal allodynia. It is uncertain where the neuropathic pain originates and how it is transmitted to the central nervous system. This study was performed in order to determine which peripheral component may lead to the symptoms of neuropathic pain. Under halothane anesthesia, male Sprague-Dawley rats were subjected to neuropathic surgery by tightly ligating and cutting the tibial and sural nerves and leaving the common peroneal nerve intact. Behavioral tests for mechanical allodynia, thermal allodynia, and spontaneous pain were performed for 2 weeks postoperatively. Subsequently, second operation was performed as follows: in experiment 1, the neuroma was removed; in experiment 2, the dorsal roots of the L4-L6 spinal segments were cut; in experiment 3, the dorsal roots of the L2-L6 spinal segments were cut. Behavioral tests were performed for 4 weeks after the second operation. Following the removal of the neuroma, neuropathic pain remained in experiment 1. After the cutting of the L4-L6 or L2-L6 dorsal roots, neuropathic pain was reduced in experiments 2 and 3. The most remarkable relief was seen after the cutting of the L2-L6 dorsal roots in experiment 3. According to the fact that the sciatic nerve is composed of the L4-L6 spinal nerves and the femoral nerve is composed of the L2-L4 spinal nerves, neuropathic pain is transmitted to the central nervous system via not only the injured nerves but also adjacent intact nerves. These results also suggest that the dorsal root ganglion is very important in the development of neuropathic pain syndrome.     

Met-enkephalin is preferentially transported into the peripheral processes of primary afferent fibres in both control and HSV1-driven proenkephalin A overexpressing rats

The demonstration of preproenkephalin A gene expression in rat dorsal root ganglia has raised the question of the physiological role of met-enkephalin-containing primary afferent fibres. Recently, we showed that systemic infection with a recombinant Herpes simplex virus encoding preproenkephalin A (HSVLatEnk1) yielded a marked increase in the density of met-enkephalin-like material synthesising neurons in rat dorsal root ganglia. This study further investigated the synthesis, transport and release of met-enkephalin-like material in the central and/or peripheral processes of primary afferent fibres in HSVLatEnk1-infected and control rats. In controls, dorsal root ganglia neurons containing met-enkephalin-like material were scarce and only a few positively labelled processes were seen at the peripheral output of the dorsal root ganglia. Met-enkephalin-like material accumulated at the proximal side of ligatured sciatic nerve, but not in ligatured L4-L5 dorsal roots. In HSVLatEnk1-infected rats with numerous somas and fibres stained for met-enkephalin-like material in dorsal root ganglia, met-enkephalin immunoreactive material largely accumulated at the proximal side of the ligatured sciatic nerve and few positively stained fibres were also observed in ligatured dorsal roots. Electrical stimulation of L4-L5 dorsal roots attached to a dorsal slice of the lumbar enlargement produced an overflow of met-enkephalin-like material which was approximately 70% higher in HSVLatEnk1-infected rats compared to controls. At the periphery, subcutaneous microdialysis showed higher basal levels of met-enkephalin-like material in the interstitial fluid of hindpaw plantar area in HSVLatEnk1-infected rats, and electrical stimulation of the ipsilateral sciatic nerve resulted in an approximately three-fold-higher overflow of this material than in control rats.These data demonstrated that met-enkephalin synthesised in dorsal root ganglion of both control and preproenkephalin A overexpressing rats is preferentially transported into the peripheral processes of primary afferent fibres where the peptide reaches a releasable compartment, thus providing a neuronal source of peripheral met-enkephalin.     

与胸12,腰1椎骨对应的腰骶神经根的应用解剖

在２０具（男１６，女４）成人尸体上，对胸１２、腰１椎骨对应的蛛网膜下隙内脊髓节、脊神经前、后根进行了应用解剖学研究。结果胸１２椎骨多与腰２￣５脊髓节、胸１２￣腰５神经根对应；腰１椎骨与骶１￣尾脊髓节、腰１￣尾脊神经根对应，据此，损伤时利于定位诊断。腰１￣３脊神经根远侧段与腰４￣骶３的近侧段之间常有一定长度的重叠，重叠的长度供神经缝接参考。文内还对神经根排列位置，前、后根的数目、长度和外径等进行了观     

Nerve root to lumbar disc relationships at the intervertebral foramen from a surgical viewpoint: An anatomical study

The objective of this study was to analyze relationship of the intervertebral disc to the nerve root in the intervertebral foramen. Fourteen formalin-fixed cadavers were studied and measurements were performed. At the medial line of the neural foramen, the disc-root distance gradually increased from L1-L2 to L5-S1. The shortest distance between the disc to nerve root was L1-L2 (mean, 8.2 mm) and the greatest distance was found at L3-L4 (mean, 10.5 mm). In the mid-foramen, the disc-root distance decreased from L1-2 to L5-S1. The shortest distance from the disc to nerve root was found at L5-S1 (mean, 0.4 mm); and the greatest distance, at L1-L2 (mean, 3.8 mm). For the lateral line, the distance between an intersection point between the medial edge of the nerve root and the superior edge of the disc and lateral line of the foramen consistently increased from L1-L2 to L5-S1. The shortest distance from nerve root to the lateral border of the foramen, at the point where the nerve root crosses disc was at level L1-L2 (mean, 2.6 mm), the greatest distance, L5-S1 (mean, 8.8 mm). The width of the foramina progressively increased in a craniocaudal direction (mean, 8.3-17.8 mm from L1-2 to L5-S1, respectively). The mean height of the foramina was more or less the same for disc levels (range, 19.3-21.5). The results showed that nerve roots at lower levels traveled closer to the midline of the foramen. This morphometric information may be helpful in minimizing the incidence of injury to the lumbar nerve root during foraminal and extraforaminal approaches.     

Repetitive training of a synchronised movement induces short-term plastic changes in the human primary somatosensory cortex

The aim of this study was to investigate the reason for the contradictory results following surgical sympathectomy on increased tactile sensitivity in spinal nerve ligated rats. For this purpose, firstly the results of L5 spinal nerve ligation alone and both L5 and L6 (L5/6) spinal nerve ligation were compared in Sprague-Dawley rats. Secondly, the difference in tactile sensitivity between the plantar surface (the middle glabrous area on the foot pads of the hind paw) and on the toe (the proximal half of the third and fourth toe of the hind paw) after the spinal nerve injury was studied. Third, we divided the L5 spinal nerve ligated rats into two groups, (i.e. low and high threshold groups) based on the degree of tactile sensitivity and investigated the effect of surgical lumbar sympathectomy (L2-L5) on tactile sensitivity in both the plantar and toe areas. The results show that the tactile sensitivities of L5 spinal nerve ligated rats and L5/6 spinal nerve ligated rats were not different. However, tactile sensitivities of the plantar surface were less than those of toe area suggesting that the response from toe is a better indicator of neuropathic pain. Surgical sympathectomy reduced the response from only the toe area and only in the low threshold group. These results suggest that the reason for the contradictory results of surgical sympathectomy in spinal nerve ligation models is, at least in part, the difference in the degree of mechanical allodynia in each study.     

The effect of sciatic nerve transection on myelinated fibers in the L5 dorsal root and lumbar dorsal column

Summary The occurrence of Marchi-positive structures (MPS) in the L5 dorsal root and lumbar dorsal column was examined 1–18 weeks after unilateral sciatic nerve transection in rats, and compared to the occurrence of MPS during Wallerian degeneration seen after transection of L4 and L5 dorsal roots. There was an increasing number of MPS centrally to the junction between the peripheral (PNS) and central nervous system (CNS) and in the lumbar dorsal column ipsilateral to sciatic nerve transection throughout the examined time period. In the portion of the root distal to the PNS-CNS junction MPS were rare before 12 weeks postoperatively after which time small groups of MPS appeared. At all stages the incidence of MPS was just a fraction of that seen during Wallerian degeneration. From these observations it is inferred that few ganglion cells with myelinated central processes undergo complete disintegration after peripheral nerve transection. In addition, some of the myelinated central ganglion cell processes appear to be more severely affected proximal to the PNS-CNS junction than distally to it.     

Bilateral changes of IL-10 protein in lumbar and cervical dorsal root ganglia following proximal and distal chronic constriction injury of peripheral nerve

Interleukin-10 prevents transition of a physiological inflammatory reaction to a pathological state that may result in neuropathic pain. We studied bilateral changes of IL-10 protein levels in L4-L5 and C7-C8 dorsal root ganglia (DRG) after a chronic constriction injury (CCI) of either L4-L5 spinal nerves (pCCI) or the sciatic nerve (dCCI). Rats undergoing pCCI or dCCI were left to survive for 1, 3, 7 or 14 d, sham-operated rats for 3 or 14 d. After the survival time, C7-C8 and L4-L5 DRG were removed bilaterally from naïve, operated, and sham-operated rats and IL-10 protein was detected by immunohistochemical staining and measured using ELISA analysis. Unilateral pCCI and dCCI induced a transient bilateral elevation in IL-10 protein level not only in the homonymous lumbar DRG but also in the heteronymous cervical DRG nonassociated with the spinal segments of constricted nerve. Sham operations also induced bilateral elevation of IL-10 protein in both homonymous and heteronymous DRG. Our experiments revealed that the more proximal is a nerve injury the more rapid is the initial increase and slower the subsequent decrease of IL-10 protein level in DRG. Changes of IL-10 protein in DRG nonassociated with damaged nerve could be related to a general neuroinflammatory reaction of the nervous system to injury and thereby promote potential of the DRG neurons for regenerating their axons following a conditioning lesion.