大白鼠丘脑—纹状体投射——HRP法研究

大白鼠尾壳核注射HRP后,在丘脑板内核群中有较多的标记细胞,并有一定的定位关系。尾壳核头部背内侧注射HRP时,标记细胞主要在板内核的背侧部;尾壳核头部腹外侧注射HRP时,标记细胞主要在板内核的腹侧部。除板内核群外,丘脑腹前核、腹外侧核及腹内侧核均有较多纤维投射到尾壳核。丘脑背内侧核和前核群可能发出少量纤维投射到尾壳核。     

大鼠中枢神经内细胞色素氧化酶与逆行辣根过氧化物酶联合反应

向大鼠单侧尾壳核注射HRP后,用氯化钴—细胞色素氧化酶组织化学反应方法,证明脑干内红核、三叉神经中脑核及耳蜗神经核等显高CO活性神经元;丘脑板内核、黑质、中缝背核及中脑被盖核等神经元呈现HRP标记;蓝斑核内可同时观察到高CO活性和HRP标记两种神经元。实验结果说明此法有可能直接用于研究脑内高CO活性神经元与其它神经元之间的联系。     

猫丘脑中央外侧核的皮质下传入联系

本实验用HRP逆行性轴浆运输技术,对猫丘脑中央外侧核的传入纤维联系及其局部定位关系进行了观察。投射至丘脑中央外侧核尾侧区的主要核团包括:外侧膝状体腹核背侧带、丘脑网状核特别是它的背侧部、上丘深层,以同侧为主。板内核、丘脑下部外侧区和黑质网状部神经元的轴突终止在同侧丘脑中央外侧核吻侧区。丘脑中央外侧核全长的传入起自脑干网状结构和前庭神经核,呈双侧投射。前者以同侧为主,后者以对侧占优势。同侧未定带,顶盖前区、动眼神经核周围的细胞群、对侧三叉神经感觉主核、楔束核、薄束核以及小脑齿状核内也含有少量标记细胞。我们还观察到HRP注射中心区位于中央外侧核并扩散至丘脑腹前核者,同侧脚内核含大量HRP阳性细胞,而Gudden被盖腹侧核内充满密集的标记终末。这些结果表明,丘脑中央外侧核可能涉及多种感觉和运动功能。     

大鼠蓝斑到脊髓的局部定位投射——荧光组织化学和HRP法联合应用的研究

在24只大鼠的颈、胸、腰、骶各段脊髓的一侧灰质注射HRP后,用荧光组化和HRP法联合应用的方法研究了蓝斑到脊髓的投射。蓝斑发出NA能纤维投射到脊髓各部并有一定的局部定位关系。蓝斑到脊髓投射的神经元主要集中在此核的腹侧部,但背侧部亦有少量授射至颈髓的神经元。蓝斑投射到颈髓的神经元主要位于蓝斑的尾侧部,而投射到骶髓的神经元主要位于颅侧部,两者有一定的重叠。     

大白鼠皮质躯体感觉区在丘脑腹后核组的定位——HRP法研究

本文用HRP法研究了20只大白鼠躯体感觉皮质区在丘脑腹后核组内的定位。鼠躯体感觉皮质区的前部接受丘脑腹后核组腹外侧部的投射;后部接受腹后核组背侧部的投射;腹后核组吻侧段外侧部的纤维投射到躯体感觉皮质区的内侧部(上部);腹后核组尾侧段内侧部的纤维投射到躯体感觉皮质区的外侧部(下部)。丘脑腹后核组内所有标记细胞均出现在注射同侧,提示丘脑皮质投射是不交叉的。丘脑腹后核组投射到Brodmann 3区的神经元多,投射到2区的神经元少。本文还探讨了标记神经元数量与投射纤维多少的关系。     

大鼠黑质—丘脑投射——HRP法研究

用 HRP 法研究了40只大白鼠的黑质—丘脑投射。将动物分为两组,一组向丘脑各核团注射 HRP,观察 SNR 中的标记细胞;另一组将 HRP 注入 SNR,观察丘脑各核团中的顺行标记纤维及终末分支。大鼠黑质—丘脑投射主要起自 SNR,但也有少量起自 SNC。SNR 全长均有细胞起始,但尾侧部较多。SNR 的背侧及腹侧均有细胞起始,但腹侧部较多。黑质—丘脑投射主要终止在 VM,但在 MD、Pf、VA 及 CL 中亦有少量终止,和猫及猴的终止部位在分布范围上基本相似,但各部在数量上有些差别。     

迷走神经背核尾侧部内神经降压肽样免疫反应终末联系的电镜研究

用辣根过氧化物酶逆行标记法结合免疫细胞化学法(PAP法)对大鼠迷走神经背核尾侧部内神经降压肽样免疫反应终末的核内联系进行了电镜下的研究.发现少量神经降压肽样免疫反应轴突终末与HRP逆行标记的副交感节前神经元的树突构成非对称性突触;大多数神经降压肽样免疫反应轴突终末与未标记中间神经元的胞体和树突构成对称性或非对称性突触,以轴-树突触为主;未标记的轴突终末也可同HRP逆行标记的副交感节前神经元的胞体和树突构成对称性或非对称性突触.由此认为核内神经降压肽样免疫反应终末可通过直接或间接联系(后者为主)作用于副交感节前神经元,从而参与对内脏、心血管活动的调节.     

大鼠三叉神经本体觉中枢通路上第三级核团内PV样阳性终末与丘脑投射神经元的突触联系

目的 观察大鼠三叉神经本体觉中枢通路上第三级核团内Paralbumin样阳性轴突终末与丘脑投射神经元之间是否存在突触联系。方法 用HRP逆行追踪和包埋前免疫电镜相结合的双重标记法。将WGA-HRP注入丘脑腹后内侧核逆行标记投射神经元。结果 WGA-HRP注入丘脑腹后内侧核(VPM)后，WGA-HRP标记神经元主要分布在感觉主核背内侧部(Vpdm)、三叉上核尾外侧部(Vsup-CL)以及三叉神经运动核腹侧区(AVM)和上橄榄核背侧区(ADO)。电镜下可见PV样阳性神经元的轴突终末与WGA-HRP标记的胞体或者树突形成突触联系。另外PV阴性神经元的轴突终末也与WGA-HRP标记的胞体或树突形成突触联系，这些胞体或树突偶尔为PV阳性。结论 在三叉神经本体感觉信息从第三级神经元向丘脑腹后内侧核(VPM)传递的过程中，PV样阳性神经元可能通过突触传递机制而发挥作用。     

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。     

大鼠丘脑前核内海马下托复合体谷氨酸能传入终末与皮质投射神经元的突触联系

目的 探讨大鼠丘脑前核-海马下托复合体神经元环路的突触结构及谷氨酸分布特征.方法 应用HRP束路追踪结合包埋后胶体金免疫电镜技术.结果 在丘脑前核内,可见HRP顺行标记的海马下托复合体传入轴突终末,终末多为卵圆形,内含圆形透亮突触小泡和数个线粒体.其做为突触前成分与HRP标记的树突或非HRP标记的树突形成非对称性突触.在谷氨酸胶体金免疫反应切片上,胶体金颗粒标记胞体、树突、轴突终末等.HRP标记的轴突终末和一些非HRP标记的与突触后成分形成非对称性突触的轴突终末(Gray Ⅰ型)内,胶体金颗粒密度明显大于背景(胞体、树突、Gray Ⅱ型轴突终末等)的胶体金颗粒密度.其平均胶体金颗粒密度为突触后树突的3倍多,为对称性轴突终末(Gray Ⅱ型)的6倍多.在两张邻近的连续切片,γ-氨基丁酸(GABA)胶体金免疫反应切片上,GABA胶体金颗粒浓重标记Gray Ⅱ型轴突终末,背景标记极少;而非对称性轴突终末(Gray Ⅰ型)胶体金颗粒标记极弱.谷氨酸胶体金免疫反应切片上,Gray Ⅱ型轴突终末胶体金颗粒标记极弱.GABA阳性轴突终末与HRP标记的树突形成对称性突触,在同一树突上可见GABA能轴突终末形成的对称性突触和其他轴突终末形成的非对称性突触.结论 丘脑前核内来自海马下托复合体投射神经元的轴突终末是谷氨酸能的;来自海马下托复合体皮质投射神经元轴突终末,在丘脑前核与投射至海马下托皮质的神经元树突形成非对称性轴-树突触.     

大鼠臂旁核向丘脑腹后内侧核的投射

目的　观察参与内脏感觉信息传递的臂旁核是否向与躯体感觉信息传递有密切关系的丘脑腹后内侧核（ＶＰＭ）投射。　方法　四甲基罗达明（ＴＭＲ）或辣根过氧化物酶（ＨＲＰ）逆行追踪和生物素葡聚糖胺（ＢＤＡ）顺行追踪技术。　结果　将ＴＭＲ或ＨＲＰ注入一侧ＶＰＭ 后,ＴＭＲ或ＨＲＰ逆标神经元主要位于同侧臂旁外侧核、ＫＦ核和臂旁内侧核;对侧臂旁外侧核和臂旁内侧核内仅见少量ＴＭＲ或ＨＲＰ逆标神经元。将ＢＤＡ注入一侧臂旁核后,ＢＤＡ顺标纤维和终末主要见于双侧ＶＰＭ、丘脑腹后外侧核、丘脑胶状质核和丘脑后核,注射区同侧的ＢＤＡ顺标纤维和终末明显多于对侧。　结论　臂旁核不仅与内脏感觉信息的传递有关,而且与躯体感觉信息的传递可能也有密切关系,并可能在躯体伤害性信息的调控中发挥重要作用。     

Influence of ascending noradrenergic fibers on the neurotensin-like immunoreactive perikarya and evidence of direct projection of ascending neurotensin-like immunoreactive fibers in the rat central nucleus of the amygdala

The influence of ascending noradrenergic neuronal input on the neurotensin (NT)-like immunoreactive neuronal perikarya located in the dorsal part of the central nucleus of the amygdala (CNA) was examined using fluorescence histochemistry and peroxidase-antiperoxidase (PAP) immunocytochemistry. Unilateral hemitransection of the ascending noradrenergic pathway by injection of 6-hydroxydopamine into the caudal mesencephalon just rostral to the locus coeruleus caused a marked depletion of immunoreactivity in NT-like immunoreactive neuronal perikarya in the CNA. Ascending noradrenergic neuronal input, therefore, is considered to facilitate production of NT-like immunoreactive substances in neuronal perikarya and to influence on the functional role of the amygdaloid complex. In addition, we obtained evidence of unilateral direct ascending projections of NT-like immunoreactive neurons into the CNA since the disappearance of NT-like immunoreactive processes occurred mainly in the ventral part of the CNA after surgical hemitransection of the ascending neuronal pathway that interrupts the ascending NT-like immunoreactive pathway arising from the neurons in the brain stem.     

Subcortical afferents to the prefrontal cortex in rabbits

Summary The origins of cells projecting to the prefrontal cortex of the rabbit were studied, using horseradish peroxidase (HRP) technique. HRP injected into the prefrontal cortex labeled cells in the basal forebrain, lateral hypothalamus, raphe nuclei and locus coeruleus area on both sides. Labeled cells appeared also in the nucleus medialis dorsalis of the thalamus and other thalamic nuclei on the injection side.     

The relationship of calbindin-containing neurons with substance P, Leu-enkephalin and cholecystokinin fibres: An immunohistochemical study in the rat thalamus

In the rat thalamus, immunoreactivity for the calcium binding protein calbindin (Cb) is mostly confined to neuronal cell bodies, sometimes revealing proximal dendrites, of the midline, intralaminar and posterior regions. Substance P (SP)-, cholecystokinin (CCK)- and Leu-enkephalin (L-ENK)-immunoreactive (ir) elements in the thalamus are fibre-like structures, intermingled with punctate elements probably representing axonal arborizations and their synaptic boutons. These peptidergic fibres are unevenly distributed in several thalamic domains, including the areas that contain Cb-ir neurons. The relationship between Cb-ir cell bodies and these three different peptidergic systems of thalamic innervation was studied with immunohistochemistry. Single-labelling experiments on adjacent sections and double immunostaining on the same section were performed. A considerable overlap between Cb-ir perikarya and SP-ir fibres was found in most thalamic nuclei. In particular, in the intralaminar nuclei and posterior complex. SP-ir punctate elements were frequently observed in close proximity to Cb-ir cell bodies and dendrites. On the other hand, no consistent topographical correspondence between Cb-ir perikarya and CCK- or L-ENK-ir fibres was evident. Altogether, the present data suggest a selective anatomical and, possibly, functional relationship between SP and Cb in at least a subpopulation of rat thalamic neurons.     

The visceral sector of the thalamic reticular nucleus in the rat.

Visceral sensory perception is subjected to modulation by attention or distraction, like other sensory systems. The thalamic reticular nucleus is a key region in selective attention, effecting a change in the mode of thalamocortical transmission. Each major thalamocortical system is connected with a particular sector of the thalamic reticular nucleus. No connections from the thalamic reticular nucleus have been described to the visceral sensory thalamus. We used axonal tracing techniques to study the possible existence of reciprocal connections between the visceral sensory relay in the lateral ventroposterior parvicellular thalamic nucleus, and the reticular nucleus of the thalamus. We also studied the projections from the visceral sensory cortex, located in the granular insular cortex in the rat, to the reticular nucleus of the thalamus. We found a convergent input from both thalamic and cortical sensory visceral regions to the same sector of the reticular nucleus of the thalamus. This visceral sector in turn sent GABAergic feedback connections to the lateral ventroposterior parvicellular thalamic nucleus. In addition, the visceral thalamus received histaminergic projections from the tuberomammillary nucleus, and noradrenergic projections from the locus coeruleus; both nuclei belong to the ascending activating system.Our findings indicate that the visceral sensory thalamocortical pathway is connected to the same subcortical structures that provide attention mechanisms for other thalamocortical systems.     

大鼠下边缘皮质的皮质下端脑,间脑,脑干的传入投射

实验用ＨＲＰ导入大鼠下边缘皮质研究了皮质下端脑、间脑和脑干至下边缘皮质的传入投射。结果：皮质下端脑至下边缘皮质的传入主要来自同侧屏状核,背侧梨状内核,杏仁基底外侧核和杏仁基底内侧核,其次来自杏仁外侧核,杏仁皮质核等。     

三角隔核和伞隔核的纤维联系——HRP及CB-HRP法研究

用HRP法及CB—HRP法研究了15只大鼠三角隔核及伞隔核的传入和传出纤维联系。结果表明:三角隔核主要接受海马、斜角带核、中缝正中核及被盖腹侧区的传入投射,也接受来自乳头体上核和蓝斑的纤维;伞隔核主要接受海马后部的传入纤维,也接受来自斜角带核、乳头体上核及被盖腹侧区的投射。三角隔核和伞隔核的传出纤维主要经髓纹终于内侧缰核,也有纤维经斜角带止于斜角带核。     

Subcortical projections to the lateral geniculate body in the rat

Summary The subcortical projections to the lateral geniculate body (LGB) in the rat were studied by means of discrete HRP iontophoretic deposits in the dorsal or the ventral LGB; the labelling was compared to that resulting from HRP deposits in neighboring nuclei.After injecting HRP in the dorsal LGB, labelled cells appeared bilaterally in the ventral LGB, pretectum, superior colliculus, lateral groups of the dorsal raphe nucleus and locus coeruleus. Ipsilaterally, labelled cells were found in the lateral posterior thalamus, nucleus of the posterior commissure and deep mesencephalic reticular nucleus.After injecting HRP into the ventral LGB, labelled cells were observed bilaterally in the pretectum, superior colliculus and dorsal raphe nucleus (lateral groups). Contralateral labelling appeared in the ventral LGB and parabigeminal nucleus. Ipsilateral labelling was found in the zona incerta, lateral posterior thalamus, lateral and medial mesencephalic reticular formation, vestibular and dorsal tegmental nuclei.These findings provide evidence of subcortical projections to the LGB arising in visually-related areas as well as extravisual areas, which might be related to the LGB boutons that survive complete cortical and retinal ablations.