大鼠腰骶髓中间带外侧核向臂旁核的投射——BDA顺行追踪研究

为了解贫办脏器感觉信息的传递道路，用结合生物素的葡聚糖妥作为顺行追踪剂，研究了大鼠腰骶髓中间带外侧核向脑桥臂旁核的投射。将ＢＤＡ注射酝中间带外侧核后，顺行标记的轴突终末出现于双侧的臂旁核，同侧略大。大量的ＢＤＡ标记的轴突终末出现于臂旁外侧核的外侧内核和外侧中央核，少量分布于外侧背核。     

大鼠展神经核和前庭神经核内GABA反应神经元向动眼神经核的投射

用辣根过氧化物酶(horseradish peroxidase,HRP)逆行标记结合γ-氨基丁酸(γ-amino-butyric acid,GABA)的免疫组织化学双标技术观察大鼠的展神经核和前庭神经核内GABA阳性神经元的分布,以及其向动眼神经核的投射。结果表明:注射HRP于大鼠动眼神经核内直肌亚核后,在对侧展神经核区以及前庭神经核、脑桥旁正中网状结构中发现HRP单标记细胞;在前庭神经核内,可见HRP单标记、GABA阳性和HRP/GABA双标记三类神经元,其中HRP/GABA双标记细胞占HRP标记细胞总数的47.1%。结果表明GABA在前庭神经核向动眼神经核的抑制性投射中起一定作用,而在展神经核向动眼神经核投射的核间通路中,可能不是起主要作用的抑制性神经递质。     

大鼠腰髓脊髓小脑束神经元向小脑中央核的投射—BDA顺行追踪研究

本实验采用 BDA顺行追踪法研究了大鼠腰髓脊髓小脑束向小脑中央核的投射。结果发现 :(1)大鼠腰髓脊髓小脑束神经元 (Clarke氏柱、第 层神经元和脊髓边缘细胞 )可向两侧小脑中央核投射 ,并以注射部位同侧的投射为主 ;(2 )大鼠腰髓脊髓小脑束向小脑中央核的投射主要分布于内侧核及间位核 ,并存在一定的体部定位关系。同时 ,首次发现有向外侧核的投射     

大鼠颈髓中央核向前庭神经外侧核的定位纤维投射

目的　探讨大鼠颈髓中央核向前庭神经外侧核的定位投射。方法　本实验通过向脊髓内单侧注射菜豆—白细胞凝集素 ,在不同节段上对由脊髓向前庭神经核的纤维投射做顺行示踪。结果　在颈髓颈 2和颈 3节段包括颈髓中央核单侧注射示踪剂后 ,应用免疫组织化学法在对侧前庭神经下核以及前庭神经内侧核的大型细胞、小型细胞部和尾部内可见大量标记终末。在对侧前庭神经外侧核由头部至尾部整个范围内 ,标记物数量最多 ;在颈膨大处单侧注射示踪剂后 ,在对侧前庭神经内侧核的大型细胞部见很多标记轴突和终末 ,但在前庭神经外侧核和前庭神经下核内 ,仅见少量标记轴突和终末。在颈膨大以下脊髓节段注射示踪剂后 ,在前庭神经内侧核的大型细胞部、前庭神经下核及前庭神经外侧核的尾部标记纤维和终末仅零星存在。结论　颈部初级传入纤维经过颈中央核中继后 ,可直接投射到对侧前庭神经外侧核 ,同时 ,研究结果亦提示颈髓中央核可能是颈部传入冲动的中继和整合之处     

大鼠前庭核向迷走神经背侧复合体的间接投射

目的：研究大鼠前庭核向迷走神经背侧复合体的间接投射,探索前庭信息向脑干呕吐区传递的神经通路。方法：向前庭神经下核和前庭神经内侧核注入顺行追踪剂菜豆凝集素（PHA-L）,向迷走神经背侧复合体注入逆行追踪剂荧光金（FG）,用免疫荧光组织化学方法显示PHA-L顺行标记纤维和终末,在荧光显微镜下观察顺行标记PHA-L的纤维和终末与FG逆行标记的细胞重叠区域。结果：在延髓外侧巨细胞旁核和腹外侧区有顺行纤维和终末与逆行标记细胞的重叠。结论：前庭核团可能经外侧巨细胞旁核和腹外侧区向迷走神经背侧复合体有间接投射,为进一步揭示前庭核团与呕吐相关的内脏反应区之间的功能关系提供了形态学基础。     

前庭神经核纤维与投射至纹状体的束旁核神经元的突触联系

目的：观察发自前庭神经内侧核的纤维末梢与投射至纹状体的丘脑束旁核神经元的突触联系。方法：采用15只Wistar大鼠,应用顺行和逆行标记技术,免疫组织化学和免疫电镜方法。结果：将CTb单侧注入纹状体,同时将BDA注入同侧的前庭神经内侧核。在束旁核发现了CTb标记神经元和BDA标记轴突终末,BDA标记纤维和终末存在于外侧束旁核整个长度的背侧2／3区,而CTb标记神经元也存在于外侧束旁核背侧2／3区,2种标记相互重叠。电镜下可见标记终末与标记神经元形成非对称性的轴-体和轴-树突触。结论：由前庭神经内侧核发出的投射纤维在束旁核与投射至纹状体的束旁核神经元之间存在着非对称性的突触联系。     

大鼠中枢神经向松果腺的投射──FastBlue逆行追踪研究

用荧光素Ｆａｓｔｂｌｕｅ逆行追踪法研究了大鼠松果腺的中枢性支配。结果发现标记细胞出现于脑内丘脑下部室旁核、丘脑下部前区、缰内侧核和缰外侧核等处，说明大鼠松果腺也接受来自中枢的神经纤维、受中枢的直接支配。     

大鼠腰髓膨大部脊髓小脑束神经元向小脑皮质的投射

将大鼠胸髓在Ｔ＿（１０）—Ｔ＿（１１）间的左侧半横切断，然后将ＷＧＡ—ＨＲＰ注入腰髓膨大部，观察标记终末（Ｌａｂｅｌｅｄｔｅｒｍｉｎａｌｓ，ＬＴ）在小脑皮质的分布。结果表明：当ＷＧＡ—ＨＲＰ注入腰髓膨大左侧时，ＬＴ主要分布在前叶（约占全部ＬＴ的７５％），其中Ⅲ和Ⅳ小叶最多（３８％和２６％），后叶较少（２５％）。ＬＴ集中分布在小叶尖端，中间部较少，基部更少。注入同侧的小脑皮质ＬＴ较多（８２％），对侧较少（１８％）。在Ⅲ和Ⅳ小叶的横切面上ＬＴ可以划分为距中线１．０～１．５ｍｍ，１．５～２．０ｍｍ，２．０～２．５ｍｍ３个集中分布区。当ＷＧＡ—ＨＲＰ注入腰髓膨大右侧时，ＬＴ主要分布在前叶（７８％），其中Ⅲ和Ⅳ小叶最多（２７％和２４％），后叶较少（２２％）。ＬＴ主要分布在小叶的中间部，小叶尖端较少，基部更少。注入部同侧小脑皮质ＬＴ较多（９０％），对侧较少（１０％）。在Ⅲ和Ⅳ小叶的横切面上它们可以区分为距中线０．５～１．０ｍｍ，１．０～１．５ｍｍ，１．５～２．０ｍｍ３个集中分布区。     

大鼠腰骶髓P物质受体阳性神经元向外侧臂旁核投射

本研究应用四甲基罗达明 (TMR)逆行追踪结合 P物质受体 (SPR)免疫荧光组织化学染色技术 ,观察了大鼠腰骶髓后连合核 (DCN)和中间带外侧核 (IML)内的 SPR阳性神经元向外侧臂旁核 (L PB)的投射。将 TMR注入一侧 L PB后 ,可在腰骶(L6 ～ S2 )节段观察到大量红色的 TMR逆标神经元 ,这些 TMR逆标神经元主要集中于 DCN和 IML内 ,多为中型 (直径 2 0～ 5μm)梭形、三角形或多极形 ;SPR阳性神经元也主要分布于 DCN和 IML内 ,并以 IML 居多 ;部分 TMR逆标神经元同时呈 SPR阳性。上述结果提示腰骶髓 DCN及 IML内的 SPR阳性神经元可能接受由 SP介导的盆腔内脏伤害性信息并将之向 LPB传递。     

大白鼠脑干至腰骶髓投射的生后发育——HRP法研究

本实验用生后1、3、5、7至35天的大白鼠18只,将50％的HRP液注入右侧脊髓腰膨大内。HRP标记细胞见于下列核团:1.中脑:红核、黑质和中缝背核。2.脑桥:脑桥吻侧网状核、脑桥尾侧网状核、蓝斑、蓝斑下核、中缝大核、前庭神经外侧核和前庭神经内侧核。3.延髓:中缝隐核、中缝苍白核、腹侧网状核、巨细胞网状核、网状外侧核、三叉神经脊束核、Cajal连合核、前置核和薄束核。各核团标记细胞数随动物的生后发育逐渐增多。表明大白鼠脑干至腰骶髓投射有一生后发育过程。红核脊髓束和蓝斑脊髓投射较网状脊髓束和前庭脊髓束成熟得晚一些。脑干至腰骶髓的投射约于生后1个月完成。     

Ipsilateral and contralateral projections from upper cervical segments to the vestibular nuclei in the rat

The present study examined uncrossed and crossed projections from upper cervical segments to the vestibular nuclei, and the relationship between the afferents and vestibulospinal neurons in the rat. Afferent axons were labeled following unilateral injections of biotinylated dextran into the C2 and C3 segments, while vestibulospinal neurons were labeled following unilateral injections of cholera toxin subunit B into the same segments. The terminals of uncrossed afferents were distributed in the entire area of the rostrocaudal extent of the lateral vestibular nucleus (LV). In the magnocellular part (MVmc) of the medial vestibular nucleus (MV), they were seen near the parvocellular part (MVpc) of the MV at caudal levels. In the MVpc, terminals were seen laterally and ventromedially, close to the border of the MVmc. At caudal levels of the caudal part (MVc) of the MV, they were distributed within the groups of labeled neurons in the middle and lateral areas. In the descending vestibular nucleus (DV), terminals were abundant dorsally and laterally in the rostral two-thirds. The distribution of contralateral cervical afferents was similar to that of ipsilateral afferents. The terminals of ipsilateral and contralateral cervical afferents were seen in contact with vestibulospinal neurons in the DV. The present study demonstrates bilateral input from upper cervical segments to the LV, DV, and all subdivisions of the MV. The input to the LV would contribute to the tonic neck reflex or cervicovestibulospinal reflex.     

A direct projection from the medial vestibular nucleus to the cervical spinal dorsal horn of the rat, as demonstrated by anterograde and retrograde tracing

Summary Phaseolus vulgaris leucoagglutinin and wheat germ agglutinin-horseradish peroxidase were iontophoretically injected into different parts of the vestibular nuclear complex (VNC) of the rat. Injections centered into the caudal part of the medial vestibular nucleus revealed a vestibulospinal projection predominantly to the dorsal horn of the cervical spinal cord, besides the expected projection to the intermediate zone (IZ) and ventral horn (VH). While most of the anterogradely labelled fibres could be localized in laminae III to V, some scattered fibres were also seen in laminae I and VI. Lamina II remained free of labelling. The dorsal horn (DH) area with detectable anterograde labelling showed a rostrocaudal extension from C₁-C₆. Injections into other parts of the VNC labelled fibres and terminals in the IZ and VH while the DH remained almost free of labelling. Additionally, fluorogold and wheat germ agglutininhorseradish peroxidase were pressure- or iontophoretically injected at different levels into the spinal cord to confirm the projection to the dorsal horn by means of retrograde tracing. Labelled neurons in the area of the medial vestibular nucleus (MVN), from which anterograde labelling in the DH was obtained, were only detectable after fluorogold and wheat germ agglutinin-horseradish peroxidase injections into the cervical spinal cord, in particular its DH. This projection from the caudal medial vestibular nucleus to the dorsal horn of the cervical spinal cord probably enables the VNC to influence sensory processing in the DH, in addition to its well-established influence on posture and locomotion via projections to the intermediate zone and ventral horn.Abbreviations BSA bovine serum albumin - CuN cuneate nucleus - CCN central cervical nucleus - cMVN caudal medial vestibular nucleus - cVST caudal vestibulospinal tract - DAB diaminobenzidine - DH dorsal horn - DRG dorsal root ganglia - DVN descending vestibular nucleus - ECN external cuneate nucleus - FCS fetal calf serum - FG fluorogold - HRP horseradish peroxidase - icp inferior cerebellar peduncle - In intercalated nucleus - IZ intermediate zone - LVN lateral vestibular nucleus - LVST lateral vestibulospinal tract - mlf medial longitudinal fasciculus - MVN medial vestibular nucleus - MVST medial vestibulospinal tract - PHA-L Phaseolus vulgaris leucoagglutinin - PrH praepositus hypoglossi nucleus - rMVN rostral medial vestibular nucleus - Ro Roller's nucleus - SVN superior vestibular nucleus - TMB tetramethylbenzidine - VH ventral horn - VNC vestibular nuclear complex - WGAHRP wheat germ agglutinin-horseradish peroxidase - 12 hypoglossal nucleus Dedicated to Prof. J.W. Rohen on the occasion of his 70th birthday     

Connections of Purkinje cell axons of lobule X with vestibulospinal neurons projecting to the cervical cord in the rat

Connections of Purkinje cell axons of lobule X (nodulus vermis) with vestibulospinal neurons have been demonstrated in the rat, by anterograde labeling of axons with biotinylated dextran (BD) injected into sublobule Xa and by retrograde labeling of neurons with cholera toxin subunit B (CTB) injected into cervical segments. Labeled terminals of Purkinje cell axons were numerous in the superior vestibular nucleus, the parvocellular (MVpc) and the caudal part (MVc) of the medial vestibular nucleus (MV), and group y. A limited number of labeled terminals were seen in the caudal part of the descending vestibular nucleus (DV). Occasional labeled terminals were seen in the lateral part of the lateral vestibular nucleus (LV) whereas few labeled terminals were seen in the magnocellular part of the MV (MVmc). Vestibulospinal neurons labeled from the C2 and C3 segments were seen bilaterally in the MVmc, MVpc, MVc, and DV, and ipsilaterally in the LV. CTB-labeled vestibulospinal neurons in contact with BD-labeled terminals of Purkinje cell axons were identified in the lateral part of the MVpc, near the border between the MVpc and MVmc, or close to the dorsal acoustic stria, and in the middle part of the MVc at its rostral level. The present study suggests that Purkinje cells of lobule X regulate the output of cervical-projecting vestibulospinal neurons in the MVpc and MVc.     

Quantitative autoradiographic characterization of l-[3H] glutamate binding sites in rat vestibular nuclei

Summary Quantitative autoradiography has been used to characterize l-[³H] glutamate binding sites and to describe their distribution in frozen sections of rat vestibular nuclei. Scatchard plots and Hill coefficients of glutamate binding suggest that glutamate interacts with a single population of sites having a K_D of about 126 nM and a capacity of 2.5 pmol/mg of protein. Although the level of glutamate binding was not very high compared to the highest levels described for some other brain regions, it was nonetheless substantial. The sites were distributed unevenly in the four vestibular nuclei and their distribution correlated well with the projection areas of the vestibular nerve, which has been described as a glutamate-mediated pathway. The highest numbers of glutamate binding sites were observed in the medial vestibular nuclei. This technique provides a very sensitive assay for characterizing the pharmacological subtypes of glutamate binding in the vestibular nuclei and for analyzing changes in these sites during development or after deafferentation of the vestibular nuclei.     

Non-cerebellar visual afferents to the vestibular nuclei involving the prepositus hypoglossal complex: An autoradiographic study in the rat

Summary Radioactive amino-acids were injected into the nucleus reticularis tegmenti pontis (NRTP) and the pretectum (PT) in the rat. Beside the labeling of the several nuclei which are known to receive afferents of either the NRTP and/or the PT, monosynaptic projections from these two structures to the prepositus hypoglossal complex (PHN) were demonstrated. Pretectal visual inputs to the vestibular nuclei (VN) may thus be conveyed not only by the classical PT-inferior olive-cerebellar route, but also by two other non-cerebellar ones involving the strong efferent projections of the PHN onto the VN. These last two pathways are strong candidates to account for the residual visual sensitivity of VN neurons after cerebellectomy or inferior olive lesions.Supported by CNRS (A.T.P. 8115)     

大鼠脊髓星形胶质细胞培养方法的改良

目的:改进大鼠脊髓星形胶质细胞的体外培养方法,为研究脊髓星形胶质细胞的生物学作用及脊髓相关疾病提供实验模型.方法:新生1～2d的SD乳鼠,无菌操作下游离整段脊柱,将脊髓从椎管中冲出,机械吹打制成单细胞悬液,差速黏附处理以去除成纤维细胞成分.利用GFAP免疫荧光显色对培养细胞进行鉴定.结果:经原代和传代培养,获得的星形胶质细胞纯化率高达99%以上.结论:采用本实验室改进的方法,操作简便快捷,培养的大鼠脊髓星形胶质细胞生长良好,纯度高,为后续实验对脊髓星形胶质细胞的生物学作用研究奠定实验基础.     

The vestibular nuclei of the cat receive a primary afferent projection from receptors in extraocular muscles

Summary The vestibular nuclei of adult cat were injected with retrogradely transported tracers, WGA-HRP or fluorescent Diamidino-Yellow. Labelled cells were found in the caudal half of the ipsilateral mesencephalic trigeminal nucleus, in the area where ganglionic cells of the sensory receptors in the extraocular muscles have previously been described. Double labelling experiments were carried out with Diamidino Yellow injected in vestibular nuclei and Fast Blue in extraocular muscles. Some cells in the mesencephalic trigeminal nucleus were found to contain both tracers, providing evidence that vestibular neurons do receive direct afferent signals from extraocular muscles. Therefore, this anatomical demonstration suggests a direct feed-back control between the extraocular muscle receptors and the vestibular nuclei.     

大鼠脊髓半横断损伤后硫酸软骨素蛋白多糖Versican的变化

目的观察大鼠脊髓半横断损伤(hSCI)位点头尾段硫酸软骨素蛋白多糖Versican的表达变化,探讨其与脊髓损伤修复的关系。方法20只成年健康SD大鼠随机分为假手术对照组和脊髓半横断损伤3d、7d和14d组。建立成年SD大鼠脊髓半横断(T9～T10)模型。取损伤位点头尾段T9、T10节段制作冰冻切片,运用Versican抗血清进行免疫组化ABC法染色。分别观察并计数各组前角中Versican阳性细胞数,采用计算机图像分析技术测量免疫阳性产物的平均光密度(A)值。结果Versican阳性产物主要分布于细胞外基质中,前角神经元和胶质细胞的胞浆中也有分布;损伤后前角中Versican阳性神经元和胶质细胞数较对照组明显减少(P<0.05),免疫阳性产物平均A值较对照组明显增加(P<0.05)。结论脊髓半横断损伤后,表达增加的Versican很可能参与损伤后轴突生长被抑制的过程。     

The vestibular nuclei in the domestic hen (Gallus domesticus). I. Normal anatomy.

Summary The topography and the cyto-and fiber architecture of the vestibular nuclear complex in the domestic hen are described as seen in transverse and horizontal thionine and myelin impregnated sections. The subdivision of the nuclear complex arrived at from these studies is discussed in the light of some experimental studies of the fiber connections of the vestibular nuclei in birds and compared with the well known organization of the vestibular nuclei in mammals.Six main vestibular nuclei are identified, the superior nucleus, the nucleus Deiters ventralis, the nucleus Deiters dorsalis, the tangential nucleus, the medial nucleus and the descending nucleus. In addition two cell groups (the cell group A and B) lying in close relation to the other nuclei are described and considered as parts of the vestibular complex. The map of the vestibular complex arrived at is largely in agreement with the maps presented by most earlier authors on other species. Furthermore, it appears that the organization of the vestibular complex in birds is more similar to the organization of the complex in mammals than hitherto recognized.     

A cerebellar projection onto the pontine nuclei in the albino rat

Summary Following removal of a significant part of the dentate nucleus and most of the interpositus nucleus in the rat cerebellum degenerated cerebellopontine fibres are shown to end in three fairly restricted regions in the contralateral pontine gray: in the paramedian position, in the middle and in the lateral third. The three regions are arranged in rostro-caudal longitudinal columns in the caudal three-quarters of the pons and these columns are continuous with one another by regions of scattered degeneration. The fibres appear to end in relation to distal dendrites of the pontine cells.This article has not been published in any journal before. The guiding principles in the care and use of animals approved by the American Physiological Society have been followed