人胎儿脊髓神经肽Y样神经元及其纤维的发育和分布的免疫细胞…

人 流产胎儿标本２３例，孕龄１０－４１周，用免疫组织化学ＡＢＣ法，研究人胎儿脊髓神经肽Ｙ样神经元的发育和分布。结果在胎龄第１０周，发现脊髓后角浅层已有神经肽Ｙ样免疫阳性神经元胞体存在，且阳性神经元总数随胎龄的增加而递增，并向后角深层扩展。神经肽Ｙ样阳性纤维，在胎龄第１０周，不仅出现了脊髓的灰质和白质，而且见于脊髓的被膜。随胎龄的增长，免疫阳性反应纤维相对集中于脊髓的植物性神经中枢的所在部位，提示在     

人胎儿脊髓神经肽Y样神经元及其纤维的发育和分布的免疫细胞化学研究

人工流产胎儿标本２３例，孕龄１０～４１周，用免疫组织化学ＡＢＣ法，研究人胎儿脊髓神经肽Ｙ样神经元的发育和分布。结果在胎龄第１０周，发现脊髓后角浅层（ＲｅｘｔｄⅠ、Ⅱ层）已有神经肽Ｙ样免疫阳性神经元胞体存在，且阳性神经元总数随胎龄的增加而递增，并向后角深层（ＲｅｘｅｄⅢ～Ⅳ层）扩展神经肽Ｙ样阳性纤维，在胎龄第１０周，不仅出现于脊髓的灰质和白质，而且见于脊髓的被膜。随胎龄的增长，免疫阳性反应纤维相对集中于脊髓的植物性神经中枢的所在部位，揭示在妊娠早期，神经肽Ｙ可能与脊髓植物神经元的发育及其功能的调节有关。     

人胎脊髓神经肽Y样神经元及其纤维的发育和分布的免疫细胞化…

收集人流胎儿标本２３例，孕龄１０－４１周，用免疫组织化学的ＡＢＣ法，研究人胎脊髓神经肽Ｙ样（ＮＰＹ－ＬＩ）神经元的发育和分布。结果在胎龄第１０周。发现脊髓后角浅层（Ｒｅｘｅｄ Ⅰ－Ⅱ）已有ＮＰＹ－ＬＩ神经元存在，且阳性神经元总数随胎龄递增，并向后角深层（ＲｅｘｅｄⅢ－Ⅵ扩展，ＮＰＹ－ＬＩ阳性纤维，在胎龄第１０周，不仅出现于脊髓的灰质和白质，而且见于脊髓被膜。随胎龄的增长，免疫性纤维相对集中于脊髓的     

人脊髓内NF样阳性神经元的形态及分布

目的：观察不同胎龄胎儿脊髓神经丝蛋白(NF)阳性神经元的形态、分布和发育变化，为脊髓-脊髓移植选择适宜的胎龄提供形态学依据。方法：胎儿脊髓19例，SP免疫组化染色，图像分析。结果：脊髓侧角内NF阳性神经元由中央管向外迁移；前角神经元由外向内迁移。NF阳性神经元密度在胚胎早期逐渐升高，晚期呈下降趋势。NF阳性神经元在胎龄16周时，胞体呈圆形、卵圆形，突起少沙，胞核大，有偏极现象，至32周时胞体呈锥形、梭形、多角形；胞体逐渐增大，胞浆逐渐增多，胞核多位居中央；突起增多。结论：未发育成熟的神经元内也有NF的存在。脊髓内NF阳性神经元密度随胎龄增加而逐渐增加，形态逐渐成熟，提示人脊髓-脊髓移植时以16周胎龄作供体较为适宜。     

人胚胎视网膜5—羟色胺样免疫反应神经元的发育

本文应用免疫细胞化学技术研究了妊娠第8周至第28周人胚胎视网膜5—羟色胺样免疫反应(5—Hydroxytryptamine like immunoreac-tion,5—HT—LI)神经元的定位和发育,观察了切片和平铺片共40例。结果表明,第10周人胚胎视网膜开始出现5—HT—LI神经元,它们分散在内成神经细胞层,胞体圆形,卵圆形,直径6—7μm。人胎第11至第13周5—HT—LI神经元数量增加,细胞大小比较一致,并处于迁移之中;此时约49.5%的5—HT—LI细胞位于节细胞层,其余位于节细胞层以外。第17至第18周位于节细胞层的5—HT—LI细胞达88.5%,位于内核层约11.5%;其中位于内核层最内缘的细胞约7.3%,这些细胞大致可分为大、中、小3型,其直径分别是8—10μm,6—7μm,和5—6μm,每平方毫米细胞数为8.1±2.19细胞(平均数±标准差)。第21周时为10.7±2.16细胞/mm~2。第14周以前可见5—HT—LI纤维分布在神经纤维层,自此之后,未见5—HT—LI纤维存在,上述结果提示,5—HT—LI神经元是发育中的无长突细胞,这些细胞在第10周人胎视网膜出现,至第17至18周已发育到相当阶段,但未见细胞间的纤维联系,此后神经元继续发育至成熟。     

神经元核心抗原和神经元特异性烯醇化酶在人胚胎脊髓发育阶段的表达

目的 探讨神经元核心抗原（NeuN）和神经元特异性烯醇化酶(NSE)在人胚胎脊髓发育阶段的分布规律及其表达意义。 方法 应用免疫组织化学法检测第2、3、4个月龄段,共16例人胚胎,脊髓前角、后角中NeuN和NSE的表达、分布状况。 结果 在脊髓后角处：第2个月胚龄段,NeuN呈阴性表达, 部分细胞呈NSE阳性表达;第3个月胎龄段,部分细胞开始呈NeuN阳性表达,NSE则呈广泛阳性表达;第4个月胎龄段,NeuN阳性细胞表达数量和强度均较前增高,NSE阳性表达与第3个月龄相似。在人胚胎脊髓前角处： 第2～4个月龄段,NeuN和NSE呈广泛阳性表达。 结论 人胚胎脊髓发育第2～4个月龄段,NeuN和NSE阳性表达在脊髓的前角处早于后角,NeuN和NSE参与脊髓神经元的发育成熟过程。     

大鼠脊髓神经肽Y、神经降压肽免疫反应神经元向结合臂旁核的投射

用HRP逆行束路追踪法结合免疫细胞化学双标记技术,研究了大鼠颈、胸、腰、骶各段脊髓神经肽Y(NPY)、神经降压肽(NT)免疫反应神经元向结合臂旁核的投射。HRP逆行标记细胞分布于两侧脊髓灰质第Ⅰ、Ⅱ、Ⅳ、Ⅴ、Ⅶ层、中央管背侧灰质连合及外侧颈核、外侧脊髓核中,以对侧为主。NPY免疫反应阳性神经元分布于两侧后角第Ⅰ层、第Ⅱ层浅部、外侧颈核、外侧脊髓核及骶髓后连合核中。NT免疫阳性神经元分布于两侧后角第Ⅰ层及第Ⅱ层中。在后角第Ⅰ层、外侧颈核和外侧脊髓核中,可观察到部分NPY-HRP双标记神经元;在后角第Ⅰ层可观察到部分NT-HRP双标记神经元。本研究结果提示,NPY和NT神经元可能参与脊髓-结合臂旁核的痛觉传递。     

人胎视皮质17区血管活性肠肽样神经元的形态、分布及个体发育

用免疫细胞化学技术,研究了人胎(19—38周,共26例)视皮质17区含血管活性肠肽(VIP)神经元的形态、分布及发育。结果证明该区含VIP神经元在受精龄第21周开始出现微弱免疫反应,阳性神经元在皮质Ⅰ—Ⅵ层均可见,但以深层Ⅴ—Ⅵ层明显,以后在Ⅱ—Ⅳ层明显增多。而且主要分布在Ⅱ—Ⅵ层。含VIP神经元有双极和多极两种,大部分是双极神经元。阳性神经元刚出现时突起短,随胎龄增长突起延长并分支。第Ⅵ层阳性神经元刚出现时胞体小,随胎龄增长(从24—38周),胞体体积明显增大,而核的比例变小。除第Ⅳ层阳性双极神经元在单位面积内的数目从36—38周有所下降外,该层阳性多极神经元数目及其他层(Ⅱ、Ⅲ、Ⅴ、Ⅵ层)阳性神经元数从24周到38周变化不明显。     

电针疗法对臂丛根性撕脱伤脊髓后角及中央管nNOS蛋白表达的影响

目的采用电针疗法干预大鼠臂丛神经撕脱伤模型,探索电针疗法对臂丛根性撕脱伤脊髓后角及中央管n NOS蛋白表达的影响。方法健康、雌性成年Sprague-Dawley(SD)大鼠共40只,行臂丛神经根性撕脱手术,随机分为撕脱伤组(AV组)和撕脱伤加电针治疗组(AV+EA组),AV+EA组动物隔日接受大椎(DU4)和手三里(LI10)电针治疗直至处死,每次治疗的输出脉冲波形为非对称双向疏密波,以20 Hz频率不间断治疗15 min。动物存活1周、2周、3周、6周处死,选取C7节段脊髓,行NADPH-d酶组织化学染色和中性红复染。结果脊髓后角,在AV组n NOS的微量表达;在AV+EA组2~3周n NOS在健侧的表达比伤侧增多,至6周脊髓后角n NOS阳性神经元表达AV组损伤侧;AV+EA组n NOS阳性神经元的表达与同时期的AV组。结论电针疗法导致脊髓后角及中央管n NOS阳性神经元的时空表达特异性。     

大白鼠脊髓前角内含片氨基丁酸神经元的化学神经解剖学研究

用HRP与免疫细胞化学结合法和免疫电镜方法观察了大白鼠脊髓L_(4～5)节段内前角含γ-氨基丁酸(GABA)神经元的分布及其与躯体传出的关系。光镜下,在脊髓前角各层,包括位于前角的前外侧部的Rexed IX层,均有GABA免疫反应阳性神经元胞体和末梢分布。GABA阳性胞体为圆形或三角形,具有多个突起,可分大、中两型。电镜下,GABA样免疫反应产物呈细小颗粒状沉淀,分布于核周质、树突和轴突内。在轴突末梢,免疫反应产物定位于小透亮囊泡和线粒体外膜周围。GABA阳性树突接受GABA阳性或阴性轴突的传入性突触。HRP与免疫细胞化学结合法显示:在Rexed IX层存在HRP单标细胞、GABA单标细胞和HRP/GABA双标细胞。双标细胞占HRP标记细胞总数的79%。以上结果证明:在Rexed IX层的前角神经细胞内含有GABA,这些神经元参与躯体传出,并在突触水平接受来自GABA神经元的自身调节。     

NPY-containing nerve terminals and fibers in close association with peptidergic sympathetic preganglionic neurons

The anatomical relationship between neuropeptide Y (NPY)-containing nerve terminals and fibers and peptidergic sympathetic preganglionic neurons (SPN) was studied immunohistochemically in cat spinal cord after colchicine administration. Terminals and fibers with NPY were found in apparent close apposition to SPN containing enkephalin-, neurotensin-, somatostatin- and substance P-like immunoreactivities along the entire thoracolumbar cord and to varying degrees. The results argue against involvement of NPY in peptide-specific pathways to peripheral organs and suggest, instead, that NPY and its association with peptidergic SPN play a more general role in the regulation of the autonomic nervous system.     

Cholecystokinin-8-like-immunoreactive fibers in rat lumbosacral autonomic regions are sexually dimorphic and altered by a reduction of androgen receptors

Cholecystokinin-8-like-immunoreactive (CCK-8-LI) fibers in laminae VII and X of the rat lumbosacral spinal cord demarcate the position of preganglionic autonomic neurons. This investigation reveals that adult male Sprague-Dawley, or King-Holtzman/Sprague-Dawley rats contain more CCK-8-LI fibers in lumbosacral laminae VII and X than adult females. Furthermore, testicular feminization mutation male rats (which lack 85-90% of their functional androgen receptors) contain fewer CCK-8-LI fibers than normal male or female rats, with the amount of CCK-8-LI being reduced to a greater extent in the sympathetic vs. the parasympathetic regions of the lumbosacral spinal cord. Thus, CCK-8-LI in testicular feminization mutation male rats has a distinctly female-like pattern. These results suggest that testosterone is a regulatory factor for CCK-8-LI fibers found in laminae VII and X of the lumbosacral spinal cord. Sexual dimorphism in lumbosacral CCK-8-LI fibers may contribute to modulating the final common pathway which differentially regulates the reproductive organs and stereotypic reproductive behavior, and may be involved with the sex differences described for pain.     

c-fos expression in rat lumbar spinal cord during the development of adjuvant-induced arthritis.

A parallel clinical and behavioral study of adjuvant-induced arthritis in the rat showed four stages in the time-course of the disease: preclinical (first week), acute (weeks 2-4), post-acute (weeks 5-8) and recovery weeks 9-11) [Calvino et al. (1987) Behav. Brain Res. 24, 11-29]. As several studies have reported the expression of the proto-oncogene c-fos in spinal cord neurons following acute noxious peripheral stimuli, the aim of this study was to quantitatively assess Fos-like immunoreactivity in lumbar spinal cord neurons at various times of adjuvant-induced arthritis development, i.e. one, two, three, 11 and 22 weeks post-inoculation. The total number of Fos-like immunoreactive neurons in the lumbar enlargement correlated with the observed development of adjuvant-induced arthritis, i.e. Fos-like immunoreactivity was absent at one week, moderate at two weeks, greatly increased at three weeks, decreased at 11 weeks and returned to control values at 22 weeks. At three weeks, at the peak of Fos-like immunoreactivity distribution and acute stage of hyperalgesia, maximal labeling was observed in L3 and L4 spinal segments. In these segments, the most densely labeled region was the neck (laminae V and VI) of the dorsal horn (55%) and the ventral horn (35%) as compared to the superficial laminae (laminae I and II; 5%) and the nucleus proprius (laminae III and IV; 5%). These data indicate that c-fos expression induced by chronic inflammation is better expressed in deeper laminae than in the superficial ones, and that the number of Fos-positive cells correlates with behavioral studies.(ABSTRACT TRUNCATED AT 250 WORDS)     

Terminations of reticulospinal fibers originating from the gigantocellular reticular formation in the mouse spinal cord

The present study investigated the projections of the gigantocellular reticular nucleus (Gi) and its neighbors—the dorsal paragigantocellular reticular nucleus (DPGi), the alpha/ventral part of the gigantocellular reticular nucleus (GiA/V), and the lateral paragigantocellular reticular nucleus (LPGi)—to the mouse spinal cord by injecting the anterograde tracer biotinylated dextran amine (BDA) into the Gi, DPGi, GiA/GiV, and LPGi. The Gi projected to the entire spinal cord bilaterally with an ipsilateral predominance. Its fibers traveled in both the ventral and lateral funiculi with a greater presence in the ventral funiculus. As the fibers descended in the spinal cord, their density in the lateral funiculus increased. The terminals were present mainly in laminae 7–10 with a dorsolateral expansion caudally. In the lumbar and sacral cord, a considerable number of terminals were also present in laminae 5 and 6. Contralateral fibers shared a similar pattern to their ipsilateral counterparts and some fibers were seen to cross the midline. Fibers arising from the DPGi were similarly distributed in the spinal cord except that there was no dorsolateral expansion in the lumbar and sacral segments and there were fewer fiber terminals. Fibers arising from GiA/V predominantly traveled in the ventral and lateral funiculi ipsilaterally. Ipsilaterally, the density of fibers in the ventral funiculus decreased along the rostrocaudal axis, whereas the density of fibers in the lateral funiculus increased. They terminate mainly in the medial ventral horn and lamina 10 with a smaller number of fibers in the dorsal horn. Fibers arising from the LPGi traveled in both the ventral and lateral funiculi and the density of these fibers in the ventral and lateral funiculi decreased dramatically in the lumbar and sacral segments. Their terminals were present in the ventral horn with a large portion of them terminating in the motor neuron columns. The present study is the first demonstration of the termination pattern of fibers arising from the Gi, DPGi, GiA/GiV, and LPGi in the mouse spinal cord. It provides an anatomical foundation for those who are conducting spinal cord injury and locomotion related research.     

Localization of acetylcholinesterase positive neurons and substance P and enkephalin positive fibers by histochemistry and immunohistochemistry in the sympathetic intermediate zone of the developing human spinal cord.

Localization of acetylcholinesterase positive neurons and substance P and enkephalin fibers were studied by histochemistry and immunohistochemistry in the intermediate sympathetic zone of the spinal cords of 39 human embryos/fetuses from gestation ages five to 40 weeks. Acetylcholinesterase positive neurons were observed in the nucleus intermediolateralis pars principalis as early as the fifth week of gestation. By the ninth to 13th weeks of gestation, positive neurons were also seen in the nuclei intermedialis pars funicularis, intercalatus spinalis and intercalatus pars paraependymalis. Increase in amount of these positive acetylcholinesterase neurons was demonstrated till term. Substance P and enkephalin fibers were initially observed by the eighth gestation week in the intermediolaterlis pars principalis nucleus and positive fibers were then detected in the nucleus intermedialis pars funicularis as well as the nucleus intercalatus spinalis by the 14th week of gestation. By the 26th week of gestation, all the major nuclei intermediolateralis par principalis, intermedialis pars funicularis, intercalatus spinalis and intercalatus pars paraependymalis has substance P and enkephalin fibers. Initial demonstration of acetylcholinesterase positive neurons appeared to be at an earlier stage than that of our substance P and enkephalin positive fibers.     

Distribution of five peptides,three general neuroendocrine markers,and two synaptic-vesicle-associated proteins in the spinal cord and dorsal root ganglia of the adult and newborn dog: An immunocytochemical study

This study describes the immunocytochemical distribution of five neuropeptides (calcitonin gene-related peptide [CGRP], enkephalin, galanin, somatostatin, and substance P), three neuronal markers (neurofilament triplet proteins, neuron-specific enolase [NSE], and protein gene product 9.5), and two synaptic-vesicle-associated proteins (synapsin I and synaptophysin) in the spinal cord and dorsal root ganglia of adult and newborn dogs. CGRP and substance P were the only peptides detectable at birth in the spinal cord; they were present within a small number of immunoreactive fibers concentrated in laminae I–II. CGRP immunoreactivity was also observed in motoneurons and in dorsal root ganglion cells. In adult animals, all peptides under study were localized to varicose fibers forming rich plexuses within laminae I–III and, to a lesser extent, lamina X and the intermediolateral cell columns. Some dorsal root ganglion neurons were CGRP- and/or substance P-immunoreactive. The other antigens were present in the spinal cord and dorsal root ganglia of both adult and newborn animals, with the exception of NSE, which, at birth, was not detectable in spinal cord neurons. Moreover, synapsin I/synaptophysin immunoreactivity, at birth, was restricted to laminae I–II, while in adult dogs, immunostaining was observed in terminal-like elements throughout the spinal neuropil. These results suggest that in the dog spinal cord and dorsal root ganglia, peptide-containing pathways complete their development during postnatal life, together with the full expression of NSE and synapsin I/synaptophysin immunoreactivities. In adulthood, peptide distribution is similar to that described in other mammals, although a relative absence of immunoreactive cell bodies was observed in the spinal cord.     

Immunohistochemical localization of enkephalin and substance P in the nucleus caudalis of the spinal trigeminal V in the medulla oblongata of the human fetus.

The distribution of enkephalin-positive neurons, substance P-positive and enkephalin-positive fibers was studied in the nucleus caudalis of the trigeminal spinal V in the medulla oblongata regions of developing humans (12 weeks gestation to 40 weeks gestation). Enkephalin-positive neurons were identified in all the subnuclei of the nucleus caudalis as early as 12 weeks of gestation and increased in number as the fetus aged. Substance P-positive neurons were absent in this area throughout development. On the other hand, substance P-positive and enkephalin-positive fibers were present in all the subnuclei, again commencing as early as 12 weeks of gestation. These fibers tended to be linked to each other in the different subnuclei and to the reticular formation in this area and to increase significantly in quantity by the latter quarter of pregnancy. These results show the early presence of these neurons and fibers in the first trimester of development.     

Developmental pattern and distribution of nerve growth factor low-affinity receptor immunoreactivity in human spinal cord and dorsal root ganglia: comparison with synaptophysin, neurofilament and neuropeptide immunoreactivities.

Immunocytochemical expression of the low-affinity nerve growth factor receptor was studied in human fetal and adult tissues using the monoclonal antibody ME20.4. In dorsal root ganglia, a few immunoreactive neurons were first detected in nine-week-old fetuses and many more were found in the following weeks of gestation. However, none was present in adult ganglia. The ME20.4-positive cells were larger than neurons immunostained by substance P, calcitonin gene-related peptide or galanin antibodies. In the spinal cord, fibres immunostained by ME20.4 appeared in a characteristic pattern that differed from the spatial and temporal distributions of synaptophysin- and neurofilament-immunoreactive fibres. Those expressing the low-affinity nerve growth factor receptor were only detected in regions containing collaterals of primary sensory axons: (i) in the dorsal funiculus between seven and 18 weeks of gestation; (ii) in a ventrodorsal bundle reaching the ventral horn from weeks 12-14; (iii) in the medial region of the dorsal horn between weeks 12 and 20; (iv) in the superficial layers and lateral portion of the dorsal horn after the 14th week of gestation and also in adult spinal cord. During the fetal period, ME20.4 immunoreactivity was also found in motoneurons and peripheral nerve fibres in the skin, myotomes and gut. Sheaths of peripheral nerves and the adventitia of blood vessels were stained both in fetal and adult tissues. Thus, the low-affinity nerve growth factor receptor is: (i) strongly expressed in the developing human nervous system; (ii) transiently associated with a subset of large primary sensory neurons and with motoneurons; (iii) transiently and sequentially expressed by various groups of sensory afferents to the spinal cord; (iv) permanently expressed by fibres in the superficial layers of the dorsal horn, Clarke's column, nerve sheaths and the adventitia of blood vessels.     

Projections from the lateral vestibular nucleus to the spinal cord in the mouse

The present study investigated the projections from the lateral vestibular nucleus (LVe) to the spinal cord using retrograde and anterograde tracers. Retrogradely labeled neurons were found after fluoro-gold injections into both the cervical and lumbar cord, with a smaller number of labeled neurons seen after lumbar cord injections. Labeled neurons in the LVe were found in clusters at caudal levels of the nucleus, and a small gap separated these clusters from labeled neurons in the spinal vestibular nucleus (SpVe). In the anterograde study, BDA-labeled fiber tracts were found in both the ventral and ventrolateral funiculi on the ipsilateral side. These fibers terminated in laminae 6–9. Some fibers were continuous with boutons in contact with motor neurons in both the medial and lateral motor neuron columns. In the lumbar and sacral segments, some collaterals from the ipsilateral vestibulospinal tracts were found on the contralateral side, and these fibers mainly terminated in laminae 6–8. The present study reveals for the first time the fiber terminations of the lateral vestibular nucleus in the mouse spinal cord and therefore enhances future functional studies of the vestibulospinal system.