A combination staining method for fibers and cell bodies of the urodele central nervous system

A simple method for staining nerve cells and fibers of the salamander central nervous system is described. The procedure employs Carnoy's fixation followed by Protargol inpregnation and Nissl staining. This technique permits the simultaneous observation of intracellular neurofibrils, neuronal processes and basophilic components of the neuron. In addition, it eliminates the need to stain alternate sections with separate procedures to view the various components of the urodele central nervous system.     

Immunomicroscopical observations on the nervous system of adult Eudiplozoon nipponicum (Monogenea: Diplozoidae)

Neuronal pathways have been examined in adult Eudiplozoon nipponicum (Monogenea: Diplozoidae), using cytochemistry interfaced with confocal scanning laser microscopy, in an attempt to ascertain the status of the nervous system. Peptidergic and serotoninergic innervation was demonstrated by indirect immunocytochemistry and cholinergic components by enzyme cytochemical methodology; post-embedding electron microscopical immunogold labelling revealed neuropeptide immunoreactivity at the subcellular level. All three classes of neuronal mediators were identified throughout both central and peripheral elements of a well-differentiated orthogonal nervous system. There was considerable overlap in the staining patterns for cholinergic and peptidergic components, while dual immunostaining revealed serotonin immunoreactivity to be largely confined to a separate set of neurons. The subcellular distribution of immunoreactivity to the flatworm neuropeptide, GYIRFamide, confirmed neuropeptide localisation in dense-cored vesicles in the majority of the axons and terminal varicosities of both central and peripheral nervous systems. Results reveal an extensive and chemically diverse nervous system and suggest that pairing of individuals involves fusion of central nerve elements; it is likely also that there is continuity between the peripheral nervous systems of the two partner worms.     

一氧化氮与神经血管单元的关联性及相关药物研究进展

一氧化氮（NO）作为一种重要的信号分子,对中枢神经系统具有重要影响。神经血管单元是近年来提出的从整体上描述中枢神经 系统的新概念,NO对中枢系统的作用是多层次多角度的,NO与神经血管单元这个整体及其各组成单元均密切相关。综述NO及其合成酶 的功能,在中枢神经系统疾病中NO与神经血管单元的相互作用关系及以NO信号通路为靶点的相关药物研究进展。     

日本三角涡虫神经系统的组织学观察

为了给涡虫神经生物学的比较研究提供基础资料和通过RNAi技术为研究与脑部再生有关基因的功能奠定基础,本研究使用石蜡连续切片技术,经HE和Masson染色后,对日本三角涡虫Dugesia japonica的神经系统进行观察.日本三角涡虫的中枢神经系统由脑和2条纵神经索组成,脑呈马蹄形;纵神经索从头部到尾部逐渐变细;脑部神经细胞突起连接成网状,纵神经索内神经细胞突起呈纵向排列;咽壁神经组织排列成内外2个圆筒状.这些结构差异反映出日本三角涡虫在涡虫纲系统演化中处于较高级的地位.     

Neurosecretion in the central nervous system of an Indian spider Oxyopes sakuntale Tikader (Araneidae: Oxyopidae)

Neurosecretory cells have been observed in the entire central nervous system of an adult Indian spider Oxyopes sakuntale Tikader. These cells are present in groups at various locations in the central nervous system. They can be divided into two types on the basis of their shape, size and cytomorphic properties. Unlike insects here the median group of pars intercerebralis has very few cells. All the neruosecretory cells have similar staining reaction and can not be differentiated into types on the basis of their staining property. Majority of the cells are circular in shape, bigger in size and dark staining. In between there are few cells which are elleptical in shape, smaller in size and light staining. They all stain green with PAF (As modified by Ewen 1962) light blue with CHP (Gomori 1941) and red with HEIDENHAINS Azan stain.     

Immunostaining to Visualize Murine Enteric Nervous System Development

The enteric nervous system is formed by neural crest cells that proliferate, migrate and colonize the gut. Following colonization, neural crest cells must then differentiate into neurons with markers specific for their neurotransmitter phenotype. Cholinergic neurons, a major neurotransmitter phenotype in the enteric nervous system, are identified by staining for choline acetyltransferase (ChAT), the synthesizing enzyme for acetylcholine. Historical efforts to visualize cholinergic neurons have been hampered by antibodies with differing specificities to central nervous system versus peripheral nervous system ChAT. We and others have overcome this limitation by using an antibody against placental ChAT, which recognizes both central and peripheral ChAT, to successfully visualize embryonic enteric cholinergic neurons. Additionally, we have compared this antibody to genetic reporters for ChAT and shown that the antibody is more reliable during embryogenesis. This protocol describes a technique for dissecting, fixing and immunostaining of the murine embryonic gastrointestinal tract to visualize enteric nervous system neurotransmitter expression.     

Leukocyte-facilitated entry of intracellular pathogens into the central nervous system

Microbes use numerous strategies to invade the central nervous system. Leukocyte-facilitated entry is one such mechanism whereby intracellular pathogens establish infection by taking advantage of leukocyte trafficking to the central nervous system. Key components of this process include peripheral infection and activation of leukocytes, activation of cerebral endothelial cells with or without concomitant infection, and trafficking of infected leukocytes to and through the blood-brain or blood-cerebrospinal fluid barrier.     

Membrane glycoproteins immunologically related to the human insulin receptor are associated with presumptive neuronal territories and developing neurones in Drosophila melanogaster

We have generated a monoclonal antibody (Mab E1C) that recognizes the differentiated nervous system in Drosophila embryos. At the cellular blastoderm stage, Mab E1C behaves as a general ectodermal marker but, in subsequent stages, it also labels the mesoderm. As neurogenesis takes place, staining increases within the neuromeres and is almost exclusively restricted to the nervous tissue by the time neuronal differentiation is completed. In third instar larvae, Mab E1C stains the central nervous system (CNS) as well as the imaginal discs which display a staining pattern related to their degree of neuronal differentiation. No labelling can be detected in adult brains or ovaries. Western blots are consistent with this developmental profile and allow the characterization of a major glycoprotein of 135 X 10(3) Mr (135K) which cosediments with a membrane fraction prepared from embryos. Additional glycoproteins (100K and 80K) are extracted from embryo homogenates by immunoaffinity procedures. In larvae, the 100K polypeptide is not detected. The properties of the 135K and 100K components are highly reminiscent of the molecular pattern of the Drosophila insulin receptor homologue (Petruzzelli et al. (1985) J. biol. Chem. 250, 16072-16075). It is shown that a Mab directed against the human insulin receptor stains the same cells as Mab E1C in imaginal discs and in the CNS. Moreover, this Mab cross-reacts with the 135K and 100K components of the embryonic antigen E1C.     

Lycopersicon esculentum lectin: an effective and versatile endothelial marker of normal and tumoral blood vessels in the central nervous system

The binding of Lycopersicon esculentum lectin (LEA) to the vascular endothelium was studied in the central nervous system of rat, mouse and guinea pig at different developmental ages, and in a gliosarcoma model. Our observations showed that LEA consistently stained the entire vascular tree in the spinal cord and in the brain of all animal species at all developmental ages investigated. In the tumor model, the staining of the vascular network was very reproducible, enabled an easy identification of vascular profiles and displayed a higher efficiency when compared to two other commonly used vascular marker (EHS laminin and PECAM-1). Moreover, our results showed that LEA staining was comparable in both vibratome and paraffin sections and could be easily combined with other markers in double labeling experiments. These observations indicate that LEA staining may represent an effective and versatile endothelial marker for the study of the vasculature of the central nervous system in different animal species and experimental conditions.     

Neural regulation of the cardiovascular system during exercise

Neural components important in control of the cardiovascular system during exercise can be divided into central nervous system (CNS) components and peripheral components. CNS components would include the cerebral cortex, cerebellum, medullary region of the brain stem, and the spinal cord. Peripheral components would include the efferent limbs of the autonomic nervous system and afferent fibers carrying information to the CNS. The neural pathways involved in the control of cardiovascular system during exercise and the relationship between the various neural components have been actively pursued in the last few years. Several new studies suggest that information arising from the active muscles and the cardiovascular system itself may be important in the control of the cardiovascular system during exercise. The cerebellum may play a modulating role in the cardiovascular response. The information from the peripheral afferent fibers, the cerebellum, and the cerebral cortex is integrated in the brain to result in overall neural control. Exercise training probably modifies the central integration of information and modifies the cardiovascular response to exercise and other stresses.     

The nervous system and the mapping of the neurons in the gastropod Helix lucorum L.]

Summarized literature and experimental author's data are presented concerning the structure of the nervous system and identification of individual neurons in the snail Helix lucorum. Information about especially well-known neurons is given in a table, maps of the ganglia are presented altogether with the results of retrograde staining of different cerebral and suboesophageal nerves. Are given the references concerning morphology of the central nervous system of the snail and identifiable neurons.     

Immunohistochemical detection of the neuronal connexin36 in the mouse central nervous system in comparison to connexin36-deficient tissues

Investigating the spatial and temporal expression of connexin36 (Cx36) protein in neuronal tissue is of prime importance to understand the molecular mechanisms underlying extensive electrical coupling. Although Cx36 mRNA was shown to be expressed in neurons of the central nervous system in different studies, only the determination of Cx36 protein expression allows a correlation between localization and its functional role in gap junction-mediated neuronal coupling. After the initial use of antibodies recognizing the skate connexin35 protein, antibodies directed to the mammalian Cx36 sequence allowed the detailed investigation of Cx36 cellular localization. However, results on Cx36 protein distribution still remained controversial in some areas of the central nervous system. In the present study, we have investigated: (a) the distribution of Cx36 protein in various areas of the central nervous system and (b) determined the specificity in the immunohistochemical staining of two polyclonal antibodies comparing wildtype and Cx36-deficient mice. In some areas of the central nervous system, for example in the retina and the inferior nuclear olivary complex, Cx36 antibodies were highly specific, and in the cerebellar cortex, Cx36 protein expression was partly specific. In other regions, particularly in pyramidal cells of the hippocampal formation, non-specific staining was prevalent, indicating that Cx36 antibodies also recognize proteins other than Cx36 in these tissues. The present results argue for a re-evaluation of many documented immunohistochemical protein distribution patterns and require, not only in connexin research, their assessment using null-mutant animals.     

slit: an EGF-homologous locus of D. melanogaster involved in the development of the embryonic central nervous system

A family of loci homologous to the EGF-like portion of Notch, a gene involved in neurogenesis, have been identified in D. melanogaster. The sequence, spatial, and temporal distribution of both RNA and protein of one of these loci suggest a possible role in the development of the central nervous system (CNS). In situ hybridization and antibody staining of embryos show initial localization in cells along the midline of the neuroepithelium. High level expression is restricted in the developing embryo to a subset of six midline glial cells abutting growing axons. Extracellular localization is suggested by the presence of EGF-like repeats in the deduced protein sequence and antibody staining. Cytological, immunocytochemical, genetic, and molecular data show that this gene corresponds to the slit locus. Mutations in this locus result in the collapse of the regular scaffold of commissural and longitudinal axon tracts in the embryonic central nervous system.     

Autoimmune disease and the nervous system. Biochemical,molecular, and clinical update.

Autoimmunity in the central and peripheral nervous system can manifest as the result of cellular or humoral immune responses to autoantigens. There is evidence that multiple sclerosis is a cell-mediated autoimmune disease of the central nervous system in which both myelin and the cell that produces the myelin are destroyed. Diseases such as acute inflammatory demyelinating polyneuropathy (also called Guillain-Barré syndrome) and myasthenia gravis are considered antibody-mediated diseases of the peripheral nervous system and neuromuscular junctions, respectively. We review these diseases and explore mechanisms of immune-mediated destruction of these nervous system components. We specifically focus on one effective therapy aimed at countering the immune attack, that of thymectomy in patients with myasthenia gravis.     

In Situ Fluorescence Imaging of Myelination

We describe a novel fluorescent dye, 3-(4-aminophenyl)-2H-chromen-2-one (termed case myelin compound or CMC), that can be used for in situ fluorescent imaging of myelin in the vertebrate nervous system. When administered via intravenous injection into the tail vein, CMC selectively stained large bundles of myelinated fibers in both the central nervous system (CNS) and the peripheral nervous system (PNS). In the CNS, CMC readily entered the brain and selectively localized in myelinated regions such as the corpus callosum and cerebellum. CMC also selectively stained myelinated nerves in the PNS. The staining patterns of CMC in a hypermyelinated mouse model were consistent with immunohistochemical staining. Similar to immunohistochemical staining, CMC selectively bound to myelin sheaths present in the white matter tracts. Unlike CMC, conventional antibody staining for myelin basic protein also stained oligodendrocyte cytoplasm in the striatum as well as granule layers in the cerebellum. In vivo application of CMC was also demonstrated by fluorescence imaging of myelinated nerves in the PNS. (J Histochem Cytochem 58:611–621, 2010)     

Morphing into cancer: the role of developmental signaling pathways in brain tumor formation

Morphogens play a critical role in most aspects of development, including expansion and patterning of the central nervous system. Activating germline mutations in components of the Hedgehog and Wnt pathways have provided evidence for the important roles morphogens play in the genesis of brain tumors such as cerebellar medulloblastoma. In addition, aberrant expression of transforming growth factor-beta (TGF-beta) superfamily members has been demonstrated to contribute to progression of malignant gliomas. This review summarizes our current knowledge about the roles of morphogens in central nervous system tumorigenesis.     

Assessing Primary Neurogenesis in Xenopus Embryos Using Immunostaining

Primary neurogenesis is a dynamic and complex process during embryonic development that sets up the initial layout of the central nervous system. During this process, a portion of neural stem cells undergo differentiation and give rise to the first populations of differentiated primary neurons within the nascent central nervous system. Several vertebrate model organisms have been used to explore the mechanisms of neural cell fate specification, patterning, and differentiation. Among these is the African clawed frog, Xenopus, which provides a powerful system for investigating the molecular and cellular mechanisms responsible for primary neurogenesis due to its rapid and accessible development and ease of embryological and molecular manipulations. Here, we present a convenient and rapid method to observe the different populations of neuronal cells within Xenopus central nervous system. Using antibody staining and immunofluorescence on sections of Xenopus embryos, we are able to observe the locations of neural stem cells and differentiated primary neurons during primary neurogenesis.     

Unique Expression of HRF20 (CD59) in Human Nervous Tissue

Damage to autologous tissue by complement is limited by several widely distributed membrane-associated glycoproteins which restrict the action of the complement in homologous species. These include decay accelerating factor (DAF), membrane cofactor protein (MCP) and 20 kDa homologous restriction factor (HRF20,CD59). Using immunohistochemical techniques, we examined the localization of these proteins in the centra] nervous system (CNS) and peripheral nervous system (PNS) using non-neurological human nervous tissue since some complement components have been demonstrated to be synthesized in the CNS. There was no evidence of parenchymal staining by anti-DAF or anti-MCP antibodies in either type of tissue except for the staining of the endothelium in capillaries. On the other hand, anti-HRF20 antibody clearly stained myelinated axons in the CNS as well as Schwann cells in the PNS. In addition, we detected positive staining by anti-DAF antibody in the PNS of a Paroxysmal nocturnal hemoglobinuria (PNH) patient who is genetically deficient in HRF20.     

The histochemical localisation of aminopeptidases in the central nervous system and an analysis of factors contributing to the final staining pattern

Summary A method is described for the localisation of aminopeptidases in the central nervous system. The enzymatic cleavage of the peptide bond in the substituted naphthylamide substrates results in the liberation of free naphthylamine which in the presence of an azo salt can be precipitated as a blue dye at sites of enzyme activity. Analysis of different brain regions using this technique indicates that these enzymes may have a specific function at certain sites in the CNS. Since this is the first method to produce any localised staining in nervous tissue an analysis of factors contributing to the final staining pattern is also presented.     

The histochemical localisation of aminopeptidases in the central nervous system and an analysis of factors contributing to the final staining pattern.

A method is described for the localisation of aminopeptidases in the central nervous system. The enzymatic cleavage of the peptide bond in the substituted naphthylamide substrates results in the liberation of free naphthylamine which in the presence of an azo salt can be precipitated as a blue dye at sites of enzyme activity. Analysis of different brain regions using this technique indicates that these enzymes may have a specific function at certain sites in the CNS. Since this is the first method to produce any localised staining in nervous tissue an analysis of factors contributing to the final staining pattern is also presented.