Ⅰ型和Ⅱ型囊泡膜谷氨酸转运体在大鼠、猫和猴脊髓内的定位分布

目的 观察Ⅰ型和Ⅱ型囊泡膜谷氨酸转运体(VGIuT1和VGIuT2)在大鼠、猫和猴脊髓内的定位分布。方法 免疫组织化学技术。结果 VGIuT1和VGIuT2在大鼠、猫和猴脊髓灰质内均有分布。VGIuT1在大鼠和猫脊髓背角Ⅱ层内侧部(Ⅱi)及Ⅲ-Ⅵ层的内侧部分布最为密集，在Ⅰ层和Ⅱ层外侧部(Ⅱo)的分布较稀疏，其他层能观察到中等密度的分布。而在猴脊髓，VGIuT1的分布与大鼠和猫有所不同，Ⅰ层、Ⅱi层、Ⅲ层及Ⅳ～Ⅵ层内侧部分布最密集，在Ⅱo层及Ⅳ-Ⅵ层外侧部较稀疏，甚至观察不到阳性结构。在猴的脊髓前角，仅在Ⅸ层观察到较稀疏的阳性产物，而其他层未见阳性产物。除此之外，在猴的脊髓后索内侧部能见到散在的阳性结构，而在大鼠和猫未观察到。VGIuT2阳性产物在3种动物脊髓灰质内均呈中等强度的分布，其中在Ⅰ层、Ⅱ层和X层内呈密集分布，在Ⅲ～Ⅵ层内侧分布较稀疏。在猴的背角深层外侧部，阳性产物非常少。在大鼠的外侧脊核(LSN)能见到中等强度的VGIuT2阳性产物，而在猫和猴中并未观察到。在3种动物脊髓中，VGIuT1和VGIuT2阳性产物均呈点状分布。结论 GIuT1和VGIuT2在3种动物脊髓内均有分布，但其分布有一定的种属差异。提示它们可能在不同动物脊髓兴奋性神经元的活动中发挥重要作用。     

小鼠脊髓神经元内脑啡肽与1型囊泡膜谷氨酸转运体的共存

目的:以PPE-GFP转基因小鼠为研究工具,观察绿色荧光蛋白(GFP)阳性的脑啡肽(ENK)能神经元与1型囊泡膜谷氨酸转运体(VGLUT1)在脊髓的分布及共存情况。方法:利用免疫组织化学和原位杂交双标染色的方法。结果:GFP标记的ENK能神经元主要位于脊髓背角,在I-ⅡI层最为密集,背角深层内侧部及中央管周围呈中等密度分布,散在分布于前角。VGLUT1 mRNA阳性细胞广泛分布在脊髓各层。GFP/VGLUT1双标细胞主要分布在脊髓背角,I-ⅡI层双标细胞占GFP阳性细胞的22.95±1.10%,占VGLUT1阳性细胞的27.91±2.42%;IV-VI层中21.49±4.99%GFP阳性细胞表达VGLUT1,10.35±2.81%VGLUT1阳性细胞表达GFP;前角双标细胞占VGLUT1阳性细胞的1.07±0.37%,占GFP阳性细胞的32.08±13.15%。结论:双标结果表明脊髓内部分ENK能神经元表达1型囊泡膜谷氨酸转运体,推测ENK能神经元可能通过调控谷氨酸的释放发挥感觉信息调控作用。     

大鼠三叉神经脊束核尾侧亚核浅层内囊泡膜谷氨酸转运体样和P物质样阳性终末与Sindibis病毒转染表达GFP神经元之间的联系

应用 GFP基因重组病毒标记技术和免疫荧光组织化学技术 ,在荧光显微镜和激光扫描共聚焦显微镜下观察了大鼠三叉神经脊束核尾侧亚核 (Vc)浅层内两种囊泡膜谷氨酸转运体 (VGlu T1样和 DNPI样 )以及 SP样阳性纤维和终末与 Sindibis病毒转染表达绿色荧光蛋白阳性神经元之间的联系。目的在于为探索兴奋性神经递质和 SP参与面口部伤害性信息在 Vc浅层内的传递和调控提供形态学依据 ;并为今后更好地开展绿色荧光蛋白基因重组病毒标记法的研究探索新路。结果显示 :(1)绿色荧光蛋白基因重组 Sindibis病毒注入一侧 Vc浅层后 ,仅在同侧 Vc注射部位附近的 ～ 层内观察到 5～ 9个绿色荧光蛋白标记神经元 ,这些神经元的胞体为小型 (≤ 15μm) ,呈圆形、多角形或不规则形 ;(2 ) Vc浅层内均可见大量的 VGlu T1样、DNPI样和 SP样阳性纤维和终末 ,其中 VGlu T1样阳性纤维和终末主要密集分布于 层的内侧部和 层 , 层和 层外侧部较为稀疏 ;而 DNPI则主要密集分布于 层和 层 , 层相对地较为稀疏 ;SP样阳性纤维和终末主要分布于 层和 层 ;(3 ) VGlu T1样、DNPI样和 SP样阳性终扣分别聚集于绿色荧光蛋白标记神经元的胞体或树突周围 ,并与之形成密切接触。以上结果提示 ,Vc浅层内两种囊泡膜谷氨酸转运体样和 SP样神经终     

大鼠三叉神经脊束核内Ⅱ型囊泡膜谷氨酸转运体样阳性终末向外侧臂旁核的投射

新近发现的Ⅰ型(VGLUT1)和Ⅱ型(VGLUT2)囊泡膜谷氨酸转运体已被作为谷氨酸能神经终末的标识物,在中枢神经系统呈互补分布,显示二者可能存在功能差异。以往的研究也已经证实接受口面部浅感觉信息的三叉神经脊束核,特别是尾侧亚核(Vc)向外侧臂旁核(LPB)发出丰富的谷氨酸能投射纤维,但该投射纤维内究竟是哪一型的囊泡膜谷氨酸转运体承担谷氨酸的转运功能,到目前为止尚未见报道。本实验选用SD大鼠,综合运用顺行束路追踪[将霍乱毒素B亚单位-CTb分别注入一侧Vc、三叉神经脊束核极间亚核(Vi)、吻侧亚核(Vo)]和免疫荧光组织化学相结合的三重标记技术,在激光共聚焦显微镜下对Vc、Vi和Vo内向LPB投射纤维内所含的囊泡膜谷氨酸转运体(VGLUTs)的情况进行了研究。结果显示:(1)将CTb分别注入大鼠一侧Vc、Vi或Vo后,在同侧的LPB内可观察到许多CTb顺行标记纤维,其中以来自Vc的标记纤维最多,Vi次之,Vo最少;(2)在LPB内可见部分CTb顺标终末同时表达VGLUT2样免疫阳性,但未见与VGLUT1样阳性终末的共存;(3)可观察到部分CTb/VGLUT2双标终末散在分布于NeuN标记的神经元的胞体周围,并与之形成密切接触。以上结果提示:大鼠口面部浅感觉、特别是伤害性信息从三叉神经脊束核向LPB传递的过程中,谷氨酸发挥着重要作用,负责其内谷氨酸转运功能的主要是VGLUT2。     

大鼠囊泡膜谷氨酸转运体样和P物质样阳性终末与三叉神经中脑核神经元的联系

最近在哺乳类动物脑内克隆出两种囊泡膜谷氨酸转运体— VGlu T1和 VGlu T2 ,目前人们已将两者作为脑内谷氨酸能终末的特异性标记物。本研究应用免疫荧光组织化学三重染色技术 ,在激光共聚焦显微镜下对大鼠三叉神经中脑核 (Vme)内VGlu T1/VGlu T2样和 P物质 (SP)样阳性终末与磷酸激活的谷氨酰胺酶 (PAG)样阳性神经元之间的联系进行了观察。结果显示 :(1) Vme内有较多的 PAG样阳性神经元 ,在吻尾方向上亘其全长出现 ,这些神经元绝大多数为大的假单极神经元 ,直径为2 5～ 5 0 μm。(2 )大量的 VGlu T1样、VGlu T2样和 SP样免疫阳性的神经纤维和终末广泛分布于 Vme内 ,其中 VGlu T2样阳性纤维和终末的分布密度高于 VGlu T1;部分 SP样阳性纤维和终末同时呈 VGlu T1样或 VGlu T2样免疫阳性。 (3 )一些 VGlu T1/VGlu T2样、SP样或 VGlu T1/VGlu T2和 SP双重标记的免疫阳性终扣分别包绕在 PAG样阳性的 Vm e神经元胞体周围 ,并与之形成密切接触。以上结果提示 :Vme神经元在将口面部本体感觉信息向更高一级中枢传递过程中 ,可能接受中枢其它来源的谷氨酸能和 SP能终末的调控 ,其中谷氨酸能的投射末梢可能通过与突触后膜上的相应受体结合而发挥作用而 SP则可能在突触前发挥间接的调控作用     

下颌神经切断术后Ⅰ型囊泡膜谷氨酸转运体在大鼠三叉神经复合体中表达的变化

目的观察下颌神经切断术后不同存活时间Ⅰ型囊泡膜谷氨酸转运体（VGluT1）样免疫阳性物质在大鼠三叉神经复合体中表达水平的变化。方法免疫细胞化学和图像分析技术。结果正常大鼠三叉神经复合体内可观察到大量的VGluT1样免疫阳性物质，且主要分布于终末内。切断一侧下颌神经后，手术侧与对照侧相比，术后存活1周组的Vp背侧部内VGluT1样阳性物质的表达有所下降（P〈0．05）；术后存活2周组的Vp背侧部、Vc背侧部、Vi背侧部，以及Vsup和Vmo内VGluT1样阳性物质的表达明显下降（P〈0．01），且与术后存活1周组手术侧比较其下降有显著差异（P〈0．05）；术后存活3周组上述部位内VGluT1样阳性物质表达的下降更加明显（P〈0．01），且与前两组手术侧相比均有显著差异（P〈0．01或P〈0．05）；其中在Vmo内的表达几乎完全消失。结论切断初级传入神经元的周围突可以导致其中枢突终末内VGluT1的表达水平下降；三叉神经复合体内部分VGluT1样阳性终末来源于外周。     

大鼠囊泡膜谷氨酸转运体和5羟色胺阳性终末与三叉神经中脑核神经元的联系(英文)

本研究应用免疫荧光组织化学三重染色技术和免疫电镜双重标记技术,对大鼠囊泡膜谷氨酸转运体 (VGluT1和VGluT2)和 5 -羟色胺(5- HT)阳性终末与三叉神经中脑核(Vme)神经元之间的联系进行了观察。在激光共聚焦显微镜下,Vme内可观察到许多磷酸激活的谷氨酰胺酶(PAG)阳性神经元,其中绝大多数为大的假单极神经元。VGluT1和VGluT2免疫阳性的神经纤维和终末广泛分布于Vme内,其中VGluT2阳性纤维和终末的分布密度高于VGluT1。在Vme内还可观察到相当数量的 5- HT阳性终末,其中部分终末同时呈VGluT2免疫阳性。一些VGluT1、VGluT2、5- HT及VGluT2 /5- HT双重标记的阳性终末与PAG阳性的Vme神经元胞体形成密切接触。在电镜下,分别用银加强的金颗粒和DAB反应产物显示VGluT1 /VGluT2和 5- HT阳性终末。在Vme内只观察到部分终末呈VGluT2和 5- HT双重免疫阳性,并且这些终末主要形成非对称性突触。以上结果提示,在口面部本体感觉信息向更高一级中枢传递过程中,谷氨酸能和 5 HT能神经终末可能通过Vme神经元对该信息进行复杂的调控。     

大鼠脊髓内囊泡膜谷氨酸转运体与星形胶质细胞之间的联系(英文)

本研究应用双重免疫荧光组织化学法观察了大鼠脊髓胶质细胞内囊泡膜谷氨酸转运体 (VGlu Ts包括 VGlu T1,VG-lu T2及 VGlu T3 )的表达状况。结果显示 :大鼠脊髓内 VGlu T1、VGlu T2和 VGlu T3样阳性轴突终末与星形胶质细胞之间形成密切接触 ;部分星形胶质细胞同时呈 VGlu T3样免疫阳性。上述结果提示 ,脊髓内谷氨酸能神经终末与星形胶质细胞之间存在着信号传递 ;且在星形胶质细胞通过胞吐作用释放谷氨酸的过程中 VGlu T3可能发挥重要作用。     

大鼠囊泡膜谷氨酸转运体样和谷氨酸脱羧酶样阳性终末与表达GABAA受体α3亚单位的三叉神经中脑核神经元之间的联系

目的 观察大鼠三叉神经中脑核(Vme)内囊泡膜谷氨酸转运体(VGluT1和DNPI)样和谷氨酸脱羧酶(GAD)样阳性终末与GABAA受体α3亚单位(GABAARα3)样阳性神经元之间的联系。方法 免疫荧光组织化学三重染色技术，在激光共聚焦显微镜下观察。结果 在Vme吻尾方向上，有大量的神经元胞体呈GABAARα3样免疫阳性，这些神经元多为大的假单极神经元(直径为25—50μm)。VGluT1样、DNPI样和GAD样免疫阳性终末密集分布于Vme内，一些VGluT1／DNPI样和GAD样阳性终末包绕在GABAARα3样阳性Vme神经元胞体周围，并与之形成密切接触。结论 Vme神经元在介导口面部本体感觉信息的传递过程中，可能同时接受中枢其他来源的谷氨酸能和GABA能终末的调控，其中GABA能终末的作用可能是通过GABAA受体实现的。     

大鼠三叉神经本体觉中枢通路中VGluT1样阳性胞体和终末的生后发育、分布以及与PAG样阳性神经元的联系

本研究应用免疫组织化学和免疫荧光组织化学技术,在光镜和激光共聚焦显微镜下观察了大鼠脑干内三叉神经本体觉中枢通路中I型囊泡膜谷氨酸转运体(VGluT1)样阳性神经元胞体和纤维终末的生后发育、表达和分布以及与磷酸激活的谷氨酰胺酶(PAG)样阳性神经元之间的联系。结果显示:(1)新生(P0)大鼠所有的三叉神经中脑核(Vme)神经元的胞体内均可观察到VGluT1的表达,3d(P3)时,VGluT1的表达最强,之后至P11,VGluT1的表达随着发育逐渐下降。P11后,在Vme神经元的胞体内未检测到VGluT1样免疫阳性产物,但在阴性胞体周围可观察到VGluT1样免疫阳性终末分布;(2)生后0d,三叉神经脊束核吻侧亚核背内侧部及其邻接的外侧网状结构(Vodm-LRF)、三叉神经感觉主核背内侧部(Vpdm)和三叉上核尾外侧部(Vsup-CL)内已可观察到VGluT1样阳性纤维终末分布。生后7d,VGluT1样阳性纤维终末开始在三叉神经运动核腹侧区(AVM)、上橄榄核背侧区(ADO)出现;(3)激光共聚焦显微镜下,于生后12d在Vme、Vodm和Vpdm内和生后21d在Vsup-CL内分别观察到一些VGluT1样阳性终末与PAG样阳性神经元的胞体或树突形成密切接触。以上结果提示:VGluT1可能与生后发育过程中大鼠脑干内三叉神经本体感觉中枢通路的兴奋性联系的建立密切相关。     

Immunohistochemical localization of the vesicular glutamate transporter VGLUT2 in the developing and adult mouse claustrum

We studied the immunoreactive expression pattern for the vesicular glutamate transporter VGLUT2 in the embryonic, postnatal and adult mouse dorsal claustrum, at the light and electron microscopic levels. VGLUT2 immunoreactivity in the dorsal claustrum starts to be observed at E16.5, with a dramatic increase towards P0. At this age, abundant VGLUT2-immunoreactive axons and puncta are observed in all pallial regions, including the claustral complex. From the first postnatal week, VGLUT2 immunoreactivity declines in several telencephalic areas, including the pallium, but abundant VGLUT2-immunoreactive fine axons and puncta remain in the claustrum. Beginning at E18.5, VGLUT2 immunoreactivity within the claustrum shows a characteristic arrangement: a central part of the region is practically devoid of VGLUT2 immunoreactivity, and it is surrounded by plenty of immunoreactive axon terminals forming a shell around it. This core/shell arrangement of the VGLUT2 immunoreactivity resembles the complementary expression of parvalbumin and calretinin described in the mouse claustrum [Real, M.A., Dávila, J.C., Guirado, S., 2003. Expression of calcium-binding proteins in the mouse claustrum. J. Chem. Neuroanat. 25, 151-160]. We observed immunoreactive neuronal cell bodies as well in the dorsal claustrum, but only at P0. Electron microscopic analysis reveals that VGLUT2 immunoreactivity in the developing and adult dorsal claustrum consists predominantly of presynaptic boutons making asymmetric synaptic contacts. These VGLUT2-immunoreactive boutons are observed as early as E16.5 and may be related to thalamo-claustral incoming fibers.     

Expression of the vesicular glutamate transporters-1 and -2 in adult mouse dorsal root ganglia and spinal cord and their regulation by nerve injury

The expression of two vesicular glutamate transporters (VGLUTs), VGLUT1 and VGLUT2, was studied with immunohistochemistry in lumbar dorsal root ganglia (DRGs), the lumbar spinal cord and the skin of the adult mouse. About 12% and 65% of the total number of DRG neuron profiles (NPs) expressed VGLUT1 and VGLUT2, respectively. VGLUT1-immunoreactive (IR) NPs were usually medium- to large-sized, in contrast to a majority of small- or medium-sized VGLUT2-IR NPs. Most VGLUT1-IR NPs did not coexpress calcitonin gene-related peptide (CGRP) or bound isolectin B4 (IB4). In contrast, approximately 31% and approximately 42% of the VGLUT2-IR DRG NPs were also CGRP-IR or bound IB4, respectively. Conversely, virtually all CGRP-IR and IB4-binding NPs coexpressed VGLUT2. Moderate colocalization between VGLUT1 and VGLUT2 was also observed. Sciatic nerve transection induced a decrease in the overall number of VGLUT1- and VGLUT2-IR NPs (both ipsi- and contralaterally) and, in addition, a parallel, unilateral increase of VGLUT2-like immunoreactivity (LI) in a subpopulation of mostly small NPs. In the dorsal horn of the spinal cord, strong VGLUT1-LI was detected, particularly in deep dorsal horn layers and in the ventral horns. VGLUT2-LI was abundant throughout the gray spinal matter, 'radiating' into/from the white matter. A unilateral dorsal rhizotomy reduced VGLUT1-LI, while apparently leaving unaffected the VGLUT2-LI. Transport through axons for both VGLUTs was confirmed by their accumulation after compression of the sciatic nerve or dorsal roots. In the hind paw skin, abundant VGLUT2-IR nerve fibers were observed, sometimes associated with Merkel cells. Lower numbers of VGLUT1-IR fibers were also detected in the skin. Some VGLUT1-IR and VGLUT2-IR fibers were associated with hair follicles. Based on these data and those by Morris et al. [Morris JL, Konig P, Shimizu T, Jobling P, Gibbins IL (2005) Most peptide-containing sensory neurons lack proteins for exocytotic release and vesicular transport of glutamate. J Comp Neurol 483:1-16], we speculate that virtually all DRG neurons in adult mouse express VGLUTs and use glutamate as transmitter.     

Differential co-localisation of the P2X7 receptor subunit with vesicular glutamate transporters VGLUT1 and VGLUT2 in rat CNS

Presynaptic P2X(7) receptors are thought to play a role in the modulation of transmitter release and have been localised to terminals with the location and morphology typical of excitatory boutons. To test the hypothesis that this receptor is preferentially associated with excitatory terminals we combined immunohistochemistry for the P2X(7) receptor subunit (P2X(7)R) with that for two vesicular glutamate transporters (VGLUT1 and VGLUT2) in the rat CNS. This confirmed that P2X(7)R immunoreactivity (IR) is present in glutamatergic terminals; however, whether it was co-localised with VGLUT1-IR or VGLUT2-IR depended on the CNS region examined. In the spinal cord, P2X(7)R-IR co-localised with VGLUT2-IR. In the brainstem, co-localisation of P2X(7)R-IR with VGLUT2-IR was widespread, but co-localisation with VGLUT1-IR was seen only in the external cuneate nucleus and spinocerebellar tract region of the ventral medulla. In the cerebellum, P2X(7)R-IR co-localised with both VGLUT1 and VGLUT2-IR in the granular layer. In the hippocampus it was co-localised only with VGLUT1-IR, including in the polymorphic layer of the dentate gyrus and the substantia radiatum of the CA3 region. In other forebrain areas, P2X(7)R-IR co-localised with VGLUT1-IR throughout the amygdala, caudate putamen, striatum, reticular thalamic nucleus and cortex and with VGLUT2-IR in the dorsal lateral geniculate nucleus, amygdala and hypothalamus. Dual labelling studies performed using markers for cholinergic, monoaminergic, GABAergic and glycinergic terminals indicated that in certain brainstem and spinal cord nuclei the P2X(7)R is also expressed by subpopulations of cholinergic and GABAergic/glycinergic terminals. These data support our previous hypothesis that the P2X(7)R may play a role in modulating glutamate release in functionally different systems throughout the CNS but further suggest a role in modulating release of inhibitory transmitters in some regions.     

大鼠脊髓背角的GABA能神经末梢来源及其突触联系──HRP追踪与免疫细胞化学结合法研究及免疫电镜观察

本文用ＨＲＰ追踪与免疫细胞化学结合法和免疫电镜技术研究了脊髓背角的ＧＡＢＡ神经元的分布、ＧＡＢＡ能末梢的来源及其超微结构联系。结果表明：在脊髓背角Ⅰ～Ⅵ层内均有ＧＡＢＡ神经元胞体和纤维分布，其中Ⅰ～Ⅲ层较为密集，在后外侧束内也存在ＧＡＢＡ能纤维及胞体。脊髓背角的ＧＡＢＡ能神经末梢有３个来源：①延髓的大缝核、隐缝核、苍白缝核及腹侧网状结构的ＧＡＢＡ能神经元；②脊髓固有的ＧＡＢＡ能神经元；③脊神经节的ＧＡＢＡ能神经元。ＧＡＢＡ能末梢可作为突触前成分或突触后成分与未标记末梢形成轴－树突触，也可同时作为突触前、后成分而形成轴－树型自调节突触。结果提示突触前的ＧＡＢＡ能末梢可能对脊髓背角内的其它神经元起抑制和脱抑制作用；同时背角内ＧＡＢＡ能神经元还接受其它神经元的调控。     

The ultrastructure of somatostatin-immunoreactive cell bodies, nerve fibers and terminals in the dorsal horn of rat spinal cord

The distribution and ultrastructure of somatostatin-immunoreactive neurons, nerve fibers and axon terminals in the dorsal horn of rat thoracic spinal cord were studied by immunohistochemistry at both the light and electron microscopic levels. Somatostatin-immuno reactive neurons were predominantly observed in Rexed laminae I and II of the dorsal horn of spinal cord. Somatostatin-immunoreactive electron dense peroxidase material was concentrated in the Golgi apparatus and rough endoplasmic reticulum of the somatostatin-immunoreactive neurons, and was characteristically sparse in other regions of the cytoplasm. In the somatostatin-immunoreactive fibers and terminals, immunoreactive electron dense material was concentrated in the microtubules and large synaptic vesicles.     

Afferent projections of the rat major occipital nerve studied by transganglionic transport of HRP

The central projection fields of cutaneous neurons of the rat's major occipital nerve have been investigated using the method of transganglionic transport of horseradish peroxidase (HRP), with tetramethylbenzidine according to Mesulam (1978) as the chromogen. Furthermore, the course of the nerve, diameter distribution of myelinated axons, and diameter distribution of HRP-labeled perikarya of spinal ganglion cells belonging to this nerve, diameter distribution of myelinated axons, and diameter distribution of HRP-labeled perikarya of spinal ganglion cells belonging to this nerve have been studied. Following HRP application to the proximal stump of the cut nerve, labeled structures were found ipsilaterally in the cervical spinal cord and in the medulla oblongata. In the spinal cord, reaction product was mainly concentrated in the lateral parts of laminae I-III of the dorsal horn in segments C2 and C3. In C1, primary afferent terminals were more sparsely distributed and restricted to laminae I and II. Reaction product was also seen in the tract of Lissauer in segments C1-C4. In the medulla oblongata HRP labeled structures were observed in the medial cuneate nucleus, in the rostral part of the external cuneate nucleus, and in the nucleus of the spinal tract of the trigeminal nerve. A possible somatotopic arrangement of central terminals of cutaneous neurons within the cervical dorsal horn, as well as differences between the projection fields of muscle and skin afferents within the upper cervical cord and caudal medulla are discussed.