RESUMEN
Background: Fluoroscopy-guided blockade of the greater occipital nerve (GON) is an accepted method for treating the symptoms of cervicogenic headaches (CGHs). However, the spread patterns among different injectate volumes of fluoroscopy-guided GON blocks are not well defined. Objective: A cadaveric study was established to determine the spread patterns of different volumes of dye injectate within a fluoroscopic GON block. Study Design. Cadaveric study. Setting. Xingtai Institute of Orthopaedics; Orthopaedic Hospital of Xingtai. Methods: 15 formalin-fixed cadavers with intact cervical spines were randomized in a 1 : 1 : 1 ratio to receive a fluoroscopy-guided GON injection of a 2, 3.5, or 5 ml volume of methylene blue. The suboccipital regions were dissected to investigate nerve involvement. Results: The suboccipital triangle regions, including the suboccipital nerves and GONs, were deeply stained in all cadavers. The third occipital nerve (TON) was stained in 7 of 10 administered 2 ml injections and in all the 3.5 ml and 5 ml injections. Compared to the 3 ml injectate group, the 5 mL cohort consistently saw injectate spreading to both superficial and distant muscles. Limitations. Given that cadavers were used in this study, cadaveric soft tissue composition and architecture can potentially become distorted and consequently affect injectate diffusion. Conclusions: A 3.5 or 5 mL fluoroscopy-guided GON injection of methylene blue successfully stains the GON, TON, and suboccipital nerves. This suggests that such an injection would generate blockade of all three nerve groups, which may contribute to the efficacy of the block for CGH. A volume of 3.5 ml may be enough for the performance of a fluoroscopy-guided GON block for therapeutic purposes.
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Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/inervación , Medios de Contraste/administración & dosificación , Bloqueo Nervioso/métodos , Nervios Espinales/diagnóstico por imagen , Anciano , Cadáver , Vértebras Cervicales/química , Vértebras Cervicales/patología , Medios de Contraste/análisis , Femenino , Fluoroscopía/métodos , Humanos , Inyecciones , Masculino , Nervios Espinales/química , Nervios Espinales/patologíaRESUMEN
Many studies examining the innervation of genitourinary structures focus on either afferent or efferent inputs, or on only one structure of the system. We aimed to clarify innervation of the bladder, external urethral sphincter (EUS) and clitoris. Retrograde dyes were injected into each end organ in female dogs. Spinal cord, mid-bladder, and spinal, caudal mesenteric, sympathetic trunk and pelvic plexus ganglia were examined for retrograde dye-labeled neurons. Neurons retrogradely labeled from the bladder were found primarily in L7-S2 spinal ganglia, spinal cord lateral zona intermedia at S1-S3 levels, caudal mesenteric ganglia, T11-L2 and L6-S2 sympathetic trunk ganglia, and pelvic plexus ganglia. The mid-bladder wall contained many intramural ganglia neurons labeled anterogradely from the pelvic nerve, and intramural ganglia retrogradely labeled from dye labeling sites surrounding ureteral orifices. Neurons retrogradely labeled from the clitoris were found only in L7 and S1 spinal ganglia, L7-S3 spinal cord lateral zona intermedia, and S1 sympathetic trunk ganglia, and caudal mesenteric ganglia. Neurons retrogradely labeled from the EUS were found in primarily at S1 and S2 spinal ganglia, spinal cord lamina IX at S1-S3, caudal mesenteric ganglia, and S1-S2 sympathetic trunk ganglia. Thus, direct inputs from the spinal cord to each end organ were identified, as well as multisynaptic circuits involving several ganglia, including intramural ganglia in the bladder wall. Knowledge of this complex circuitry of afferent and efferent inputs to genitourinary structures is necessary to understand and treat genitourinary dysfunction. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc.
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Clítoris/inervación , Neuronas , Nervios Espinales , Uretra/inervación , Vejiga Urinaria/inervación , Animales , Clítoris/química , Clítoris/citología , Colorantes/administración & dosificación , Perros , Femenino , Neuronas/química , Nervios Espinales/química , Nervios Espinales/citología , Coloración y Etiquetado/métodos , Uretra/química , Uretra/citología , Vejiga Urinaria/química , Vejiga Urinaria/citologíaRESUMEN
Nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) enzymatic activity has been reported in few amphibian species. In this study, we report its unusual localization in the medulla oblongata, spinal cord, cranial nerves, spinal nerves, and ganglions of the frog, Microhyla ornata. In the rhombencephalon, at the level of facial and vagus nerves, the NADPH-d labeling was noted in the nucleus of the abducent and facial nerves, dorsal nucleus of the vestibulocochlear nerve, the nucleus of hypoglossus nerve, dorsal and lateral column nucleus, the nucleus of the solitary tract, the dorsal field of spinal grey, the lateral and medial motor fields of spinal grey and radix ventralis and dorsalis (2-10). Many ependymal cells around the lining of the fourth ventricle, both facial and vagus nerves and dorsal root ganglion, were intensely labeled with NADPH-d. Most strikingly the NADPH-d activity was seen in small and large sized motoneurons in both medial and lateral motor neuron columns on the right and left sides of the brain. This is the largest stained group observed from the caudal rhombencephalon up to the level of radix dorsalis 10 in the spinal cord. The neurons were either oval or elongated in shape with long processes and showed significant variation in the nuclear and cellular diameter. A massive NADPH-d activity in the medulla oblongata, spinal cord, and spinal nerves implied an important role of this enzyme in the neuronal signaling as well as in the modulation of motor functions in the peripheral nervous systems of the amphibians.
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Nervios Craneales/química , Bulbo Raquídeo/química , NADPH Deshidrogenasa/análisis , Médula Espinal/química , Nervios Espinales/química , Animales , Anuros , Nervios Craneales/citología , Femenino , Masculino , Bulbo Raquídeo/citología , Neuronas Motoras/química , Neuronas Motoras/citología , Médula Espinal/citología , Nervios Espinales/citologíaRESUMEN
Quantitative observation of nerve fiber sections is often complemented by morphological analysis in both research and clinical condition. However, existing manual or semi-automated methods are tedious and labour intensive, fully automated morphometry methods are complicated as the information of color or gray images captured by traditional microscopy is limited. Moreover, most of the methods are time-consuming as the nerve sections need to be stained with some reagents before observation. To overcome these shortcomings, a molecular hyperspectral imaging system is developed and used to observe the spinal nerve sections. The molecular hyperspectral images contain both the structural and biochemical information of spinal nerve sections which is very useful for automatic identification and quantitative morphological analysis of nerve fibers. This characteristic makes it possible for researchers to observe the unstained spinal nerve and live cells in their native environment. To evaluate the performance of the new method, the molecular hyperspectral images were captured and the improved spectral angle mapper algorithm was proposed and used to segment the myelin contours. Then the morphological parameters such as myelin thickness and myelin area were calculated and evaluated. With these morphological parameters, the three dimension surface view images were drawn to help the investigators observe spinal nerve at different angles. The experiment results show that the hyperspectral based method has the potential to identify the spinal nerve more accurate than the traditional method as the new method contains both the spectral and spatial information of nerve sections.
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Algoritmos , Citometría de Imagen/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Microscopía Acústica/métodos , Fibras Nerviosas Mielínicas/ultraestructura , Reconocimiento de Normas Patrones Automatizadas/métodos , Nervios Espinales/ultraestructura , Animales , Automatización , Color , Colorantes , Femenino , Citometría de Imagen/instrumentación , Imagenología Tridimensional , Microcomputadores , Microscopía Acústica/instrumentación , Vaina de Mielina/química , Vaina de Mielina/ultraestructura , Fibras Nerviosas Mielínicas/química , Conejos , Nervios Espinales/química , Coloración y EtiquetadoRESUMEN
Retrograde labeling of neurons is a standard anatomical method(1,2) that has also been used to load calcium and voltage-sensitive dyes into neurons(3-6). Generally, the dyes are applied as solid crystals or by local pressure injection using glass pipettes. However, this can result in dilution of the dye and reduced labeling intensity, particularly when several hours are required for dye diffusion. Here we demonstrate a simple and low-cost technique for introducing fluorescent and ion-sensitive dyes into neurons using a polyethylene suction pipette filled with the dye solution. This method offers a reliable way for maintaining a high concentration of the dye in contact with axons throughout the loading procedure.
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Axones/química , Colorantes Fluorescentes/química , Neuronas/química , Raíces Nerviosas Espinales/química , Nervios Espinales/química , Coloración y Etiquetado/métodos , Animales , Dextranos/química , Fluoresceínas/química , Neuronas/citología , Raíces Nerviosas Espinales/anatomía & histología , Raíces Nerviosas Espinales/citología , Nervios Espinales/anatomía & histología , Nervios Espinales/citología , Coloración y Etiquetado/instrumentaciónRESUMEN
Notalgia paraesthetica is a neuropathic pruritus on the back. The aim of this retrospective study was to examine patient characteristics in a consecutive cohort from Brazil and Germany. A total of 65 patients (49 women, 16 men; age range 25-80 years, mean 56.2 ± 12.7 years; median 57.0 years) were investigated in order to determine the spinal or peripheral origin of notalgia paraesthetica. Protein gene product 9.5-positive intraepidermal nerve fibers were significantly reduced in the pruritic compared with the non-lesional area (p < 0.05). In 32.3% of patients, radiological examinations showed a stenosis and in 47.7% a degeneration. A correlation between the radiological findings and the exact dermatomal localization of notalgia paraesthetica was found in 15.7% of the involved areas. The significant reduction in intraepidermal nerve fiber density suggests that damage to the peripheral nerves is a more important aetiological factor than spinal changes in notalgia paraesthetica.
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Nervios Periféricos/patología , Enfermedades del Sistema Nervioso Periférico/patología , Prurito/patología , Piel/inervación , Adulto , Anciano , Anciano de 80 o más Años , Dorso , Biomarcadores/análisis , Biopsia , Brasil/epidemiología , Femenino , Alemania/epidemiología , Humanos , Inmunohistoquímica , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Nervios Periféricos/química , Enfermedades del Sistema Nervioso Periférico/epidemiología , Prurito/diagnóstico por imagen , Prurito/epidemiología , Estudios Retrospectivos , Piel/patología , Compresión de la Médula Espinal/diagnóstico por imagen , Compresión de la Médula Espinal/epidemiología , Compresión de la Médula Espinal/patología , Nervios Espinales/química , Nervios Espinales/patología , Tomografía Computarizada por Rayos X , Ubiquitina Tiolesterasa/análisisRESUMEN
BACKGROUND: Brain tumors are one of the leading cancers worldwide; in the National Institute of Neurology and Neurosurgery (INNN) these tumors are the leading cause of morbitity and mortality. OBJECTIVE: Standardize biopsies, colletion, processing and storage biologic material of molecular studies. METHODS: with a previously signed surgical consent, a tumor and blood biopsy was done to 134 patients. Their DNA was extracted and a database was filled considering technical, ethical and legal aspects. In order to have optimal biologic material the procedure was standardized between the surgical and research laboratory teams. RESULTS: The biopsy, transportation, processing and storage were standardized. 134 patients were included (67 male and 67 female) with an average age of 46.28 years (range 15-81). The most frequently biopsied tumor was the meningioma (42%). The integrity of the obtained material was determined by agarose gel electrophoretic analysis. CONCLUSION: the INNN biobank has a standardized system that biopsies, processes and stores optimum quality biologic material that will be the basis of future molecular studies.
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Bancos de Muestras Biológicas/normas , Neoplasias del Sistema Nervioso Central/patología , ADN de Neoplasias , Meningioma/patología , Neoplasias Neuroepiteliales/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bancos de Muestras Biológicas/organización & administración , Biopsia/normas , Sistema Nervioso Central/química , Sistema Nervioso Central/patología , Neoplasias del Sistema Nervioso Central/química , Neoplasias del Sistema Nervioso Central/genética , Neoplasias del Sistema Nervioso Central/secundario , Neoplasias de los Nervios Craneales/química , Neoplasias de los Nervios Craneales/genética , Neoplasias de los Nervios Craneales/patología , ADN de Neoplasias/análisis , ADN de Neoplasias/genética , ADN de Neoplasias/aislamiento & purificación , Bases de Datos Factuales , Electroforesis en Gel de Agar , Femenino , Humanos , Masculino , Meningioma/química , Meningioma/genética , México , Persona de Mediana Edad , Neoplasias Neuroepiteliales/química , Neoplasias Neuroepiteliales/genética , Neoplasias del Sistema Nervioso Periférico/química , Neoplasias del Sistema Nervioso Periférico/genética , Neoplasias del Sistema Nervioso Periférico/patología , Preservación Biológica/métodos , Preservación Biológica/normas , Garantía de la Calidad de Atención de Salud , Manejo de Especímenes/normas , Nervios Espinales/química , Nervios Espinales/patología , Transportes/normas , Adulto JovenRESUMEN
Vertebral fractures often cause intractable pain. To define the involvement of vertebral body innervation in pain, we collected specimens from male and female patients during percutaneous kyphoplasty, a procedure used for reconstruction of the vertebral body. Specimens were taken from 31 patients (9 men and 22 women) suffering high-intensity pain before surgery. In total, 1,876 histological preparations were obtained and analysed. Immunohistochemical techniques were used to locate the nerves in the specimens. The nerve fibres were labelled by indirect immunofluorescence with the primary antibody directed against Protein Gene Product 9.5 (PGP 9.5), a pan-neuronal marker; another primary antibody directed against type IV collagen (Col IV) was used to identify vessels and to determine their relationship with vertebral nerve fibres. The mean percentage of samples in which it was possible to identify nerve fibres was 35% in men and 29% in women. The percentages varied depending on the spinal level considered and the sex of the subject, nerve fibres being mostly present around vessels (95%). In conclusion, there is scarce innervation of the vertebral bodies, with a clear prevalence of fibres located around vessels. It seems unlikely that this pattern of vertebral body innervation is involved in vertebral pain or in pain relief following kyphoplasty.
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Fracturas por Compresión/fisiopatología , Vértebras Lumbares/inervación , Dolor Intratable/fisiopatología , Fracturas de la Columna Vertebral/fisiopatología , Nervios Espinales/fisiopatología , Vértebras Torácicas/inervación , Adulto , Anciano , Anciano de 80 o más Años , Colágeno Tipo IV/análisis , Femenino , Técnica del Anticuerpo Fluorescente , Fracturas por Compresión/cirugía , Humanos , Vértebras Lumbares/cirugía , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Dolor Intratable/cirugía , Índice de Severidad de la Enfermedad , Fracturas de la Columna Vertebral/cirugía , Nervios Espinales/química , Vértebras Torácicas/cirugía , Resultado del Tratamiento , Ubiquitina Tiolesterasa/análisis , VertebroplastiaRESUMEN
The nociceptive nature of spinal dorsal horn neurons expressing NK1 and gamma-aminobutyric acid (GABA)(B) receptors was evaluated in the rat. Immunodetection of the Fos protein, induced by noxious mechanical stimulation of the skin, was combined with immunocytochemistry for NK1 or GABA(B) receptors (double-immunostaining study) or both receptors (triple-immunostaining study). Neurons double-labeled for Fos and for each receptor largely prevailed in lamina I. The proportions of Fos-positive cells immunostained for NK1 or GABA(B) receptors were higher in lamina I than in the remaining spinal laminae. More Fos-positive cells were immunoreactive (IR) for GABA(B) receptors than for NK1 in all dorsal horn laminae. In the triple-immunostaining study, co-localization of NK1 and GABA(B) receptors occurred only in lamina I and was higher in neurons expressing Fos. As to the morphological lamina I cell class, NK1-positive cells belonged mainly to the fusiform type while similar proportions of fusiform, pyramidal and flattened NK1 neurons expressed GABA(B) receptors. No differences were found between those cell types as to the degree of nociceptive activation. The present results suggest that the co-localization of NK1 and GABA(B) receptors is a common feature of fusiform, pyramidal and flattened neurons in lamina I. Considering the participation of the three cell classes in various ascending systems, it is concluded that a simultaneous action of substance P (SP) and GABA may play an important role in the modulation of nociceptive input supraspinally transmitted from lamina I.
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Dolor/metabolismo , Células del Asta Posterior/metabolismo , Receptores de GABA-B/biosíntesis , Receptores de Neuroquinina-1/biosíntesis , Nervios Espinales/metabolismo , Animales , Inmunohistoquímica , Masculino , Dolor/patología , Dimensión del Dolor/métodos , Células del Asta Posterior/química , Ratas , Ratas Wistar , Receptores de GABA-B/análisis , Receptores de Neuroquinina-1/análisis , Nervios Espinales/químicaRESUMEN
Caveolae are a specific plasmalemmal microdomain which appear as flask-like invaginations and/or vesicles attaching just beneath the plasmalemma. Caveolae are present in many cell types and are found in the Schwann cells that ensheath myelinated and unmyelinated nerve fibers of the peripheral nervous tissues. However, the precise distribution in the Schwann cell plasmalemma and the functional properties of these caveolae remains obscure. The present study revealed: (1) Caveolae are most commonly observed in the Schwann cell plasmalemma of myelinated nerve fibers. (2) Caveolae are principally located in the perikaryal plasmalemma of Schwann cells of the myelinated nerves. (3) Caveolin-1 is expressed strongly in Schwann cell caveolae. (4) Caveolin 2 and 3 are also immunohistochemically detected in Schwann cell caveolae, although the immunoreactivities are slight. The results suggested that caveolae of the peripheral nervous system are involved in cellular activities specific to Schwann cells in myelinated nerve fibers. These caveolae may contain receptors for signaling molecules that could affect the myelinated nerve fibers, and/or proteins related to ion transfer activity. Further studies are necessary in order to clarify the types of proteins associated with Schwann cell caveolae.
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Caveolas/ultraestructura , Caveolinas/análisis , Células de Schwann/ultraestructura , Nervios Espinales/ultraestructura , Animales , Caveolina 1 , Caveolina 2 , Caveolina 3 , Técnica de Fractura por Congelación , Inmunohistoquímica , Masculino , Microscopía Electrónica de Transmisión , Ratas , Células de Schwann/química , Nervios Espinales/químicaRESUMEN
OBJECTIVE: The first quantitative analysis of the innervation of the lumbar intervertebral disc is presented. METHODS: A sheep model was used allowing evaluation of the whole motion segment. Four sheep spines were used. One was processed for PGP 9.5 immunofluorescence and three were processed for PGP 9.5 immunoperoxidase histochemistry. A count was made of the densities of innervation of the endplate and anulus, and these were compared. RESULTS: There is no significant difference between endplate and anulus innervation densities. The endplate innervation is concentrated centrally adjoining the nucleus. The richest area of innervation is in the perianular connective tissue. DISCUSSION: The lumbar intervertebral disc has a meager innervation. This is concentrated in the perianular connective tissue and the central endplate. Although receptor threshold is more closely related to nociceptive function than innervation density, these findings have important implications for any treatment of discogenic pain.
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Disco Intervertebral/inervación , Nervios Espinales/anatomía & histología , Animales , Biomarcadores/análisis , Técnicas para Inmunoenzimas , Disco Intervertebral/anatomía & histología , Microscopía Fluorescente , Proteínas del Tejido Nervioso/análisis , Ovinos , Nervios Espinales/químicaRESUMEN
We report here the pattern of axonal branching for 11 descending cell types in the larval brainstem; eight of these cell types are individually identified neurons. Large numbers of brainstem neurons were retrogradely labeled in living larvae by injecting Texas-red dextran into caudal spinal cord. Subsequently, in each larva a single identified cell was injected in vivo with Alexa 488 dextran, using fluorescence microscopy to guide the injection pipette to the targeted cell. The filling of cells via pressure pulses revealed distinct and often extensive spinal axon collaterals for the different cell types. Previous fills of the Mauthner cell had revealed short, knob-like collaterals. In contrast, the two segmental homologs of the Mauthner cell, cells MiD2cm and MiD3cm, showed axon collaterals with extensive arbors recurring at regular intervals along nearly the full extent of spinal cord. Furthermore, the collaterals of MiD2cm crossed the midline at frequent intervals, yielding bilateral arbors that ran in the rostral-caudal direction. Other medullary reticulospinal cells, as well as cells of the nucleus of the medial longitudinal fasciculus (nMLF), also exhibited extensive spinal collaterals, although the patterns differed for each cell type. For example, nMLF cells had extensive collaterals in caudal medulla and far-rostral spinal cord, but these collaterals became sparse more caudally. Two cell types (CaD and RoL1) showed arbors projecting ventrally from a dorsally situated stem axon. Additional cell-specific features that seemed likely to be of physiological significance were observed. The rostral-caudal distribution of axon collaterals was of particular interest because of its implications for the descending control of the larva's locomotive repertoire. Because the same individual cell types can be identified from fish to fish, these anatomical observations can be directly linked to data obtained in other kinds of experiments. For example, 9 of the 11 cell types examined here have been shown to be active during escape behaviors.
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Tronco Encefálico/anatomía & histología , Tronco Encefálico/crecimiento & desarrollo , Neuronas/citología , Nervios Espinales/citología , Pez Cebra/anatomía & histología , Animales , Transporte Axonal/fisiología , Tronco Encefálico/química , Tronco Encefálico/enzimología , Colorantes Fluorescentes/análisis , Inmunohistoquímica , Larva , Neuronas/química , Tractos Piramidales/anatomía & histología , Tractos Piramidales/química , Tractos Piramidales/embriología , Tractos Piramidales/crecimiento & desarrollo , Nervios Espinales/química , Nervios Espinales/embriología , Pez Cebra/embriología , Pez Cebra/crecimiento & desarrolloRESUMEN
We produced a monoclonal antibody, named A20, which specifically recognizes a 35 kDa protein and stains myelinated axons in zebrafish brain. The A20 antigen is located at the outside of the myelin layer of large axons, and comprises a fine meshwork composed of thin unit fibers about 1-2 microm in length and about 100-200 nm in thickness. The unit fibers form pentagonal and hexagonal structures, which further polymerize into an envelope structure on the axons. The A20 monoclonal antibody did not stain neuronal cell bodies nor synapses. Instead, the distribution of the A20 antigen was along axons, practically coincident with the distribution of myelin basic protein. The monoclonal antibody stained only axons in the central nervous system (CNS), and not the extracellular matrix surrounding Schwann cells. These results suggest that this antigenic meshwork (which we call the periaxonal net) is synthesized by oligodendrocytes. During the development of the zebrafish brain, the periaxonal net appeared after the formation of myelin on the axons. The periaxonal net developed first at the brain stem, then gradually appeared at the caudal end of the spinal cord. The thickness of the periaxonal net around the Mauthner axon changed during development. Although the thickness of the Mauthner axon continues to grow throughout life, the thickness of periaxonal net stopped growing at 6 months after fertilization.
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Antígenos de Superficie/análisis , Axones/química , Sistema Nervioso Central/química , Sistema Nervioso Central/crecimiento & desarrollo , Proteínas de la Mielina/análisis , Vaina de Mielina/química , Pez Cebra , Animales , Anticuerpos Monoclonales , Antígenos de Superficie/inmunología , Técnica del Anticuerpo Fluorescente , Immunoblotting , Inmunohistoquímica , Oligodendroglía/metabolismo , Nervio Óptico/química , Nervios Espinales/químicaRESUMEN
Spontaneously hypertensive rats (SHR) exhibit enhanced pressor, heart rate, and nociceptive responses to spinal nicotinic agonists. This accompanies a paradoxical decrease in spinal nicotinic receptor number in SHR compared with normotensive rats. The congenic strain, SHR-Lx, with an introgressed chromosome 8 segment from the normotensive Brown-Norway-Lx strain (BN-Lx) exhibits reduced blood pressure. This segment contains a gene cluster for three nicotinic receptor subunits expressed in the nervous system. We examined the implication of this gene cluster in the enhanced responsiveness of the SHR. Pressor and nociceptive responses to spinal cytisine, a nicotinic agonist, were diminished in SHR-Lx. Moreover, with repeated administration, these responses desensitized faster in SHR-Lx and progenitor BN-Lx than in progenitor SHR/Ola. This implicates the gene cluster in both cardiovascular and nociceptive responses to spinal nicotinic agonists. Since diminished responsiveness to agonist stimulation is greater than the basal blood pressure differences between the strains and the introgressed rat chromosome maps to a quantitative trait locus in human hypertension, polymorphisms in the three nicotinic receptor genes become candidates for altered central control of blood pressure.
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Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/genética , Cromosomas/genética , Hipertensión/genética , Familia de Multigenes/genética , Receptores Nicotínicos/genética , Alcaloides/administración & dosificación , Alcaloides/metabolismo , Animales , Animales Congénicos , Azocinas , Esquema de Medicación , Tolerancia a Medicamentos/fisiología , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/genética , Inyecciones Espinales , Masculino , Agonistas Nicotínicos/administración & dosificación , Agonistas Nicotínicos/metabolismo , Quinolizinas , Ratas , Ratas Endogámicas BN , Ratas Endogámicas SHR , Nervios Espinales/química , Nervios Espinales/efectos de los fármacos , Cola (estructura animal)/irrigación sanguíneaRESUMEN
The overall distribution of the actin cytoskeleton in perineurial cells of rat spinal nerves was examined by confocal laser and thin-section electron microscopy. Confocal laser microscopy of whole-mount nerves stained with fluorescent-labelled phalloidin revealed two types of actin bundles in perineurial cells; stress fiber-type actin bundles and circumferential actin bundles. The degree of development of the actin cytoskeleton varied in different segments of different nerves. Stress fiber-type actin bundles were also immunostained for myosin and vinculin and were well-developed in the perineurial cells of large-sized nerves and dorsal root ganglia, whereas they were poor in spinal nerve root sheaths within the subarachnoid space. In peripheral nerves, stress fiber-type actin bundles tended to be arranged transverse to the nerve axis. Circumferential actin bundles were localized along intercellular junctions, which were immunostained with several junctional proteins such as alpha-catenin, occludin and ZO-1. Thin-section electron microscopy confirmed the distribution pattern of actin bundles observed by confocal laser microscopy. These findings suggest that actin bundles may play some roles in structurally stabilizing the perineurium by providing mechanical support for the cell layers as well as cell junctions to maintain perineurial integrity and form diffusion barriers in peripheral nerves.
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Citoesqueleto de Actina/ultraestructura , Actinas/análisis , Nervios Periféricos/química , Nervios Periféricos/ultraestructura , Nervios Espinales/química , Animales , Masculino , Microscopía Confocal , Microscopía Electrónica , Microscopía Fluorescente , Ratas , Ratas Wistar , Nervios Espinales/ultraestructuraRESUMEN
Neuropilins are receptors for class 3 secreted semaphorins, most of which can function as potent repulsive axon guidance cues. We have generated mice with a targeted deletion in the neuropilin-2 (Npn-2) locus. Many Npn-2 mutant mice are viable into adulthood, allowing us to assess the role of Npn-2 in axon guidance events throughout neural development. Npn-2 is required for the organization and fasciculation of several cranial nerves and spinal nerves. In addition, several major fiber tracts in the brains of adult mutant mice are either severely disorganized or missing. Our results show that Npn-2 is a selective receptor for class 3 semaphorins in vivo and that Npn-1 and Npn-2 are required for development of an overlapping but distinct set of CNS and PNS projections.
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Axones/fisiología , Proteínas Portadoras/metabolismo , Glicoproteínas/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Factores de Edad , Animales , Axones/química , Química Encefálica/fisiología , Células COS , Eliminación de Gen , Regulación del Desarrollo de la Expresión Génica , Habénula/química , Habénula/embriología , Habénula/patología , Ratones , Ratones Noqueados , Fibras Musgosas del Hipocampo/química , Fibras Musgosas del Hipocampo/embriología , Fibras Musgosas del Hipocampo/patología , Neuronas Motoras/química , Neuronas Motoras/fisiología , Neuronas Motoras/ultraestructura , Neuropilina-1 , Sistema Nervioso Periférico/química , Sistema Nervioso Periférico/embriología , Sistema Nervioso Periférico/patología , Unión Proteica/fisiología , Ratas , Semaforina-3A , Nervios Espinales/química , Nervios Espinales/patología , Nervios Espinales/fisiología , Ganglio Cervical Superior/química , Ganglio Cervical Superior/embriología , Ganglio Cervical Superior/patología , Tálamo/química , Tálamo/embriología , Tálamo/patología , Nervio Troclear/química , Nervio Troclear/embriología , Nervio Troclear/patologíaRESUMEN
BACKGROUND/PURPOSE: Calcitonin gene-related peptide (CGRP) has been proposed to influence migration and testicular descent by release from the genitofemoral nerve. The site of CGRP within the nerve has been controversial, with conflicting views on whether CGRP is synthesised and released from the motor nerves. METHODS: The genitofemoral nerve (GFN) was retrogradely labelled by fluorescent dye (DAPI) in 25 Sprague-Dawley rats (days 5, 16, and 31, n = 8 in each group; day 35, n = 1). Spinal cords and dorsal root ganglia (DRG) were removed two to three days later and sectioned for immunofluorescence. Substance P and CGRP-containing cells were labelled with fluorescein-linked antibodies. Specimens were examined by double fluorescence to identify cells with both markers. RESULTS: The motor nucleus of the GFN contained 119 cells on day 7 and 284 cells by days 19 through 34. A prominent band of CGRP-containing fibers, arising from the dorsal horn, synapsed with the GFN motor nucleus itself. CGRP-labelled GFN cells were found in the DRG by double labelling. CONCLUSIONS: CGRP from the GFN may affect gubernacular migration by release from the sensory nerves, rather than motor nerves as previously thought. The GFN motor nucleus receives CGRP-containing innervation from the dorsal horn, which may form part of the cremasteric reflex.
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Péptido Relacionado con Gen de Calcitonina/análisis , Nervios Espinales/química , Animales , Animales Recién Nacidos , Ganglios Espinales/química , Neuronas Motoras/metabolismo , Ratas , Ratas Sprague-Dawley , Sustancia P/metabolismoRESUMEN
This study focuses on changes in adrenergic sensitivity in untransected sensory axons that innervate an area of skin made neuropathic by transection of neighboring nerves. The segmental nerve injury model is favorable for this since all axons in the L5 and L6 nerves are transected whereas the L4 axons are intact. Earlier findings are that pain behaviors develop after this injury and that these behaviors are ameliorated by sympathectomy. The present study shows that behavior indicating mechanical allodynia can be rekindled after sympathectomy by intradermal norepinephrine and alpha-2 but not alpha-1 adrenergic ligands and the rekindling can be blocked by alpha-2 but not alpha-1 adrenergic antagonists. By contrast neither intradermal norepinephrine nor other adrenergic agonists or antagonists have any demonstrable effects in the normal or after either neuropathic surgery or sympathectomy alone. These data suggest that the combination of neuropathic surgery and sympathectomy results in an upregulation of active alpha-2 adrenergic receptors on the undamaged sensory axons that provide the remaining sensory innervation to a neuropathic area partially denervated by segmental nerve lesions. These changes on undamaged axons presumably compliment similar changes on the transected axons and, thus play a role in the development of neuropathic pain.
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Agonistas alfa-Adrenérgicos/farmacología , Causalgia/fisiopatología , Neuronas Aferentes/fisiología , Norepinefrina/farmacología , Sistema Nervioso Simpático/fisiopatología , Antagonistas Adrenérgicos alfa/farmacología , Animales , Conducta Animal/fisiología , Clonidina/farmacología , Idazoxan/farmacología , Masculino , Neuronas Aferentes/química , Neuronas Aferentes/efectos de los fármacos , Fenilefrina/farmacología , Estimulación Física , Ratas , Ratas Sprague-Dawley , Nervios Espinales/química , Nervios Espinales/citología , Nervios Espinales/fisiopatología , Simpatectomía , Sistema Nervioso Simpático/citología , Sistema Nervioso Simpático/cirugía , Yohimbina/farmacologíaRESUMEN
Injury to a peripheral nerve induces in the dorsal root ganglia (DRG) sprouting of sympathetic and peptidergic terminals around large-diameter sensory neurons that project in the damaged nerve. This pathological change may be implicated in the chronic pain syndromes seen in some patients with peripheral nerve injury. The mechanisms underlying the sprouting are not known. Using in situ hybridization and immunohistochemical techniques, we have now found that nerve growth factor (NGF) and neurotrophin-3 (NT3) synthesis is upregulated in satellite cells surrounding neurons in lesioned DRG as early as 48 h after nerve injury. This response lasts for at least 2 months. Quantitative analysis showed that the levels of mRNAs for NT3 and NGF increased in ipsilateral but not contralateral DRG after nerve injury. Noradrenergic sprouting around the axotomized neurons was associated with p75-immunoreactive satellite cells. Further, antibodies specific to NGF or NT3, delivered by an osmotic mini-pump to the DRG via the lesioned L5 spinal nerve, significantly reduced noradrenergic sprouting. These results implicate satellite cell-derived neurotrophins in the induction of sympathetic sprouting following peripheral nerve injury.
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Factores de Crecimiento Nervioso/genética , Neuroglía/metabolismo , Neuronas Aferentes/citología , Nervio Ciático/lesiones , Animales , Anticuerpos/farmacología , Axotomía , Cartilla de ADN , Ganglios Espinales/citología , Expresión Génica/fisiología , Proteína Ácida Fibrilar de la Glía/análisis , Hibridación in Situ , Macrófagos/química , Masculino , Factores de Crecimiento Nervioso/inmunología , Neuroglía/química , Neuroglía/efectos de los fármacos , Neuronas Aferentes/química , Neuronas Aferentes/efectos de los fármacos , Neurotrofina 3 , Norepinefrina/farmacología , ARN Mensajero/análisis , Ratas , Ratas Sprague-Dawley , Receptor de Factor de Crecimiento Nervioso , Receptores de Factor de Crecimiento Nervioso/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Nervio Ciático/citología , Nervio Ciático/inmunología , Nervios Espinales/química , Nervios Espinales/citología , Nervios Espinales/lesiones , Simpatomiméticos/farmacología , Tirosina 3-Monooxigenasa/análisisRESUMEN
AIM: Analysis of developmental role of fibronectin during differentiation of the human spinal cord, nerves, and ganglia. METHODS: Seven normal human embryos and fetuses between the 7th and 9th developmental week and a 9-week fetus with cervical spina bifida were histologically examined on hematoxylin and eosin stained serial paraffin sections of thoracic axial segments. Monoclonal antibody to the human cell fibronectin fragment was used for immunohistochemical detection of fibronectin. RESULTS: In the 7th and 8th week of development, fibronectin was weakly expressed in the ventricular and intermediate zones of the spinal cord. Intense fibrillar expression was found in the marginal zone of the spinal cord - first over the ventral gray horns and later over the lateral and dorsal gray horns, and along the pathways of ventral and dorsal roots of the spinal nerves and in the spinal ganglia. At 9th week, fibronectin expression disappeared in the ventricular and intermediate zones a nd became weak and granular in the marginal zone of the spinal cord. In the spinal cord of a 9-week malformed fetus with cervical spina bifida, fibronectin expression was completely absent. Fibronectin was expressed in the nerves and ganglia throughout the investigated period, both in normal and malformed human conceptuses. CONCLUSION: Transient expression of fibronectin in the human spinal cord coincided with the most intense neuronal differentiation. Temporal and spatial expression of fibronectin during normal development, and its absence in a malformed human fetus suggests developmental role of fibronectin for the normal formation of the spinal cord.