RESUMO
OBJETIVO: Estudo dos ventrículos cerebrais por ultrassonografia, com o objetivo de estabelecer de forma simplificada parâmetros para diagnóstico das dilatações ventriculares leves. MATERIAIS E MÉTODOS: Foram estudadas, prospectivamente, 105 crianças, normais, nascidas a termo, com um total de 181 exames realizados, mensalmente até os 6 meses, através da observação de dados morfológicos e medidas. As medidas efetuadas foram: índice ventrículo/hemisfério, diâmetro anteroposterior do corno anterior e do quarto ventrículo. RESULTADOS: Obtiveram-se média, desviopadrão e percentis de normalidade das medidas estabelecidas, em cada faixa etária. A pesquisa de halo anecoico nos dois terços posteriores do plexo coroide em plano coronal VI, para avaliação dos cornos temporal/posterior, foi ausente, e o terceiro ventrículo mostrou-se como uma fenda anecoica, menor que 1 mm, em plano coronal V em todas as crianças do estudo. CONCLUSÃO: Os achados morfológicos relacionados aos cornos temporal/posterior e ao terceiro ventrículo, associados ao percentil 95 das medidas como limite superior da normalidade, podem ser utilizados para diagnóstico simplificado de dilatações ventriculares leves.
OBJECTIVE: Study of the cerebral ventricular system by ultrasonography with the objective of establishing parameters for the diagnosis of mild ventricular dilatation. MATERIALS AND METHODS: Prospective study of 105 healthy, full term infants aged 1-6 months, submitted to monthly scans for morphological data evaluation and measurements of ventricle/ hemisphere ratio, and anteroposterior diameter of frontal horn and fourth ventricle. RESULTS: Normality mean, standard deviation and percentile were obtained for each age range. Negative results were observed in the search for anechoic halo surrounding the posterior two thirds of the choroid plexus on coronal section VI for evaluation of temporal/posterior horns, and the third ventricle was seen as an anechoic cleft < 1 mm on coronal section V in all of the evaluated infants. CONCLUSION: Sonographic findings related to temporal/posterior horns and third ventricle associated with the 95th percentile as upper limit of normality can be utilized as parameters for a simplified diagnosis of mild ventricular dilatation.
Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Ventrículos Cerebrais , Estudos Prospectivos , Ventrículos Cerebrais/anatomia & histologia , Ventrículos Cerebrais/fisiologia , Ventrículos Cerebrais , Cérebro/fisiologiaRESUMO
An increasing number of studies have evaluated the potential therapeutic relevance of histone deacetylases (HDAC) inhibitors in mood disorder including bipolar disorder (BD). It has been suggested that the anterior limbic, which controls impulsivity and psychosis, is dysfunctional in BD. The present studies aims to evaluate the effects of microinjection of HDAC inhibitors in the ventricle, amygdala, striatum, prefrontal, and hippocampus on m-amphetamine-induced manic-like behavior in rats. Rats were given a single intracerebral (in the ventricle, amygdala, striatum, prefrontal, or hippocampus) injection of artificial cerebrospinal fluid, sodium butyrate (SB), or valproate (VPA) followed by an intraperitoneal injection of saline or m-AMPH 2 h before the open-field task. The activity of HDAC was evaluated in amygdala, striatum, prefrontal, and hippocampus of animals. The microinjection of SB and VPA in the ventricle, amygdala, striatum, and prefrontal, but not in hippocampus blocked the hyperactivity induced by m-AMPH. In addition, SB and VPA inhibited the HDAC activity; however, this effect varied depending on the experimental procedure and the brain structure evaluated. Our results suggest that the antimanic effects of SB and VPA, HDAC inhibitors, are related to the amygdala, striatum, and prefrontal, but not the hippocampus. More studies are needed to clarify the therapeutic effects of the HDAC inhibitor in BD and thereby develop new drugs.
Assuntos
Antimaníacos/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Sistema Nervoso/anatomia & histologia , Sistema Nervoso/efeitos dos fármacos , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/fisiologia , Animais , Butiratos/administração & dosagem , Butiratos/farmacologia , Ventrículos Cerebrais/efeitos dos fármacos , Ventrículos Cerebrais/fisiologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Masculino , Microinjeções , Neostriado/efeitos dos fármacos , Neostriado/fisiologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiologia , Ratos , Ratos Wistar , Ácido Valproico/administração & dosagem , Ácido Valproico/farmacologiaRESUMO
Demyelinating diseases are characterized by an extensive loss of oligodendrocytes and myelin sheaths from axolemma. These neurological disorders are a common cause of disability in young adults, but so far, there is no effective treatment against them. It has been suggested that neural stem cells (NSCs) may play an important role in brain repair therapies. NSCs in the adult subventricular zone (SVZ), also known as Type-B cells, are multipotential cells that can self-renew and give rise to neurons and glia. Recent findings have shown that cells derived from SVZ Type-B cells actively respond to epidermal-growth-factor (EGF) stimulation becoming highly migratory and proliferative. Interestingly, a subpopulation of these EGF-activated cells expresses markers of oligodendrocyte precursor cells (OPCs). When EGF administration is removed, SVZ-derived OPCs differentiate into myelinating and pre-myelinating oligodendrocytes in the white matter tracts of corpus callosum, fimbria fornix and striatum. In the presence of a demyelinating lesion, OPCs derived from EGF-stimulated SVZ progenitors contribute to myelin repair. Given their high migratory potential and their ability to differentiate into myelin-forming cells, SVZ NSCs represent an important endogenous source of OPCs for preserving the oligodendrocyte population in the white matter and for the repair of demyelinating injuries.
Assuntos
Ventrículos Cerebrais/citologia , Doenças Desmielinizantes/patologia , Fator de Crescimento Epidérmico/fisiologia , Regeneração Nervosa/fisiologia , Células-Tronco Neurais/citologia , Oligodendroglia/citologia , Animais , Diferenciação Celular/fisiologia , Movimento Celular/fisiologia , Proliferação de Células , Ventrículos Cerebrais/fisiologia , Doenças Desmielinizantes/fisiopatologia , Doenças Desmielinizantes/terapia , Fator de Crescimento Epidérmico/farmacologia , Humanos , Fibras Nervosas Mielinizadas/metabolismo , Fibras Nervosas Mielinizadas/ultraestrutura , Células-Tronco Neurais/fisiologia , Oligodendroglia/fisiologiaRESUMO
Cardiovascular responses elicited by the stimulation of kinin B2 receptors in the IV cerebral ventricle, paratrigeminal nucleus or in the thoracic spinal cord are similar to those observed during an exercise bout. Considering that the kalikrein-kinin system (KKS) could act on the cardiovascular modulation during behavioral responses as physical exercise or stress, this study evaluated the central B2 receptor densities of Wistar (W) and spontaneously hypertensive rats (SHR) after chronic moderate exercise. Animals were exercise-trained for ten weeks on a treadmill. Afterwards, systolic blood pressure decreased in both trained strains. Animals were killed and the medulla and spinal cord extracted for B2 receptor autoradiography. Trained animals were compared to their sedentary controls. Sedentary groups showed specific binding sites for Hoe-140 (fmol/mg of tissue) in laminas 1 and 2 of the spinal cord, nucleus of the solitary tract (NTS), area postrema (AP), spinal trigeminal tract (sp5) and paratrigeminal nucleus (Pa5). In trained W a significant increase (p<0.05) in specific binding was observed in the Pa5 (31.3%) and NTS (28.2%). Trained SHR showed a significant decrease in receptor density in lamina 2 (21.9%) of the thoracic spinal cord and an increase in specific binding in Pa5 (36.1%). We suggest that in the medulla, chronic exercise could hyper stimulate the KKS enhancing their efficiency through the increase of B2 receptor density, involving this receptor in central cardiovascular control during exercise or stress. In the lamina 2, B2 receptor might be involved in the exercise-induced hypotension.
Assuntos
Ventrículos Cerebrais/metabolismo , Condicionamento Físico Animal/fisiologia , Receptor B2 da Bradicinina/metabolismo , Animais , Pressão Sanguínea/fisiologia , Ventrículos Cerebrais/irrigação sanguínea , Ventrículos Cerebrais/fisiologia , Calicreínas/fisiologia , Cininas/fisiologia , Masculino , Bulbo/irrigação sanguínea , Bulbo/metabolismo , Bulbo/fisiologia , Ratos , Ratos Endogâmicos SHR , Ratos Wistar , Receptor B2 da Bradicinina/biossíntese , Medula Espinal/irrigação sanguínea , Medula Espinal/metabolismo , Medula Espinal/fisiologia , Estresse Fisiológico , Fatores de Tempo , Regulação para Cima/fisiologiaRESUMO
El primer procedimiento neuroendoscópico fue realizado por Lespinasse en 1910 y Dandy, doce años después, manifestó la utilidad de estos procedimientos. En Argentina Roque Orlando y Manuel Balado, trabajando por separado, publicaron sus experiencias en 1931, dejando establecidas las indicaciones y potencialidades de la endoscopía. Durante el año 1932, un segundo informe de Balado, menciona que Payr, en 1919, había expresado la posibilidad de utilizar la endoscopía con fines experimentales, y comentó el trabajo publicado por Volkmann en 1923. En la década del '70, Conesa y Dillon comenzaron los estudios de neuroanatomía endoscópica en Argentina, arribando a conclusiones que hoy se consideran verdades absolutas. Finalmente, en el año 2001, los autores crearon el primer laboratorio de neuroanatomía endoscópica en el país
Assuntos
História do Século XXI , Endoscopia , História , História da Medicina , Neuroanatomia , Ventrículos Cerebrais/fisiologia , ArgentinaRESUMO
El primer procedimiento neuroendoscópico fue realizado por Lespinasse en 1910 y Dandy, doce años después, manifestó la utilidad de estos procedimientos. En Argentina Roque Orlando y Manuel Balado, trabajando por separado, publicaron sus experiencias en 1931, dejando establecidas las indicaciones y potencialidades de la endoscopía. Durante el año 1932, un segundo informe de Balado, menciona que Payr, en 1919, había expresado la posibilidad de utilizar la endoscopía con fines experimentales, y comentó el trabajo publicado por Volkmann en 1923. En la década del 70, Conesa y Dillon comenzaron los estudios de neuroanatomía endoscópica en Argentina, arribando a conclusiones que hoy se consideran verdades absolutas. Finalmente, en el año 2001, los autores crearon el primer laboratorio de neuroanatomía endoscópica en el país
Assuntos
História do Século XXI , Endoscopia , Ventrículos Cerebrais/fisiologia , Neuroanatomia , História , História da Medicina , ArgentinaRESUMO
We have recently reported that the central heme oxygenase (HO) pathway has an important role in the genesis of lipopolysaccharide fever. However, the HO product involved, i.e., biliverdine, free iron, or carbon monoxide (CO), has not yet been identified with certainty. Therefore, in the present study, we tested the thermoregulatory effects of all HO products. Body core temperature (T(c)) and gross activity of awake, freely moving rats was measured by biotelemetry. Intracerebroventricular administration of heme-lysinate (152 nmol), which induces the HO pathway, evoked a marked increase in T(c), a response that was attenuated by intracerebroventricular pretreatment with the HO inhibitor zinc deuteroporphyrin 2,4-bis glycol (200 nmol), indicating that an HO product has a pyretic action in the central nervous system (CNS) of rats. Besides, heme-lysinate also increased gross activity, but no correlation was found between this effect and the increase in T(c). Moreover, intracerebroventricular biliverdine or iron salts at 152 nmol, a dose at which heme-lysinate was effective in increasing T(c), produced no change in T(c). Accordingly, intracerebroventricular treatment with the iron chelator deferoxamine elicited no change in basal T(c) and did not affect heme-induced pyresis. However, heme-induced pyresis was completely prevented by the soluble guanylate cyclase (sGC) inhibitor 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxaline-1-one. Because biliverdine and iron had no thermoregulatory effects and CO produces most of its actions via sGC, these data strongly imply that CO is the only HO product with a pyretic action in the CNS.
Assuntos
Dióxido de Carbono/fisiologia , Deuteroporfirinas/farmacologia , Febre/fisiopatologia , Heme Oxigenase (Desciclizante)/metabolismo , Animais , Biliverdina/administração & dosagem , Biliverdina/farmacologia , Regulação da Temperatura Corporal , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Ventrículos Cerebrais/efeitos dos fármacos , Ventrículos Cerebrais/fisiologia , Desferroxamina/farmacologia , Deuteroporfirinas/administração & dosagem , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Escherichia coli , Febre/induzido quimicamente , Heme Oxigenase (Desciclizante)/antagonistas & inibidores , Injeções Intraventriculares , Ferro/metabolismo , Lipopolissacarídeos/toxicidade , Masculino , Oxidiazóis/farmacologia , Quinoxalinas/farmacologia , Ratos , Ratos WistarRESUMO
Microglial cells within the developing central nervous system (CNS) originate from mesodermic precursors of hematopoietic lineage that enter the nervous parenchyma from the meninges, ventricular space and/or blood stream. Once in the nervous parenchyma, microglial cells increase in number and disperse throughtout the CNS; these cells finally differentiate to become fully ramified microglial cells. In this article we review present knowledge on these phases of microglial development and the factors that probably influence them.
Assuntos
Humanos , Animais , Sistema Nervoso Central/crescimento & desenvolvimento , Microglia/fisiologia , Apoptose/fisiologia , Ventrículos Cerebrais/fisiologia , Meninges/fisiologia , Microglia/citologia , Microglia/metabolismo , Mitose/fisiologiaRESUMO
We have studied gap junctional communication in the anterior subventricular zone (SVZa) of postnatal rodents, revealed by intercellular diffusion of dyes in brain slices. Extensive intercellular dye spread was evident in the SVZa. Coupling was not uniform, being characteristically larger in the outer borders of this layer, overlapping the previously described peripheral zone of concentration of S-phase cells. Intercellular spread of the dye was unaffected by acidification, but totally blocked by high Ca(2+) concentrations. In addition, application of some known uncoupling agents as carbenoxolone and halothane led to a marked reduction of dye spread in the SVZa. Our results demonstrate the presence of dye coupling mediated by gap junctions in the SVZa. Furthermore, the spatial organization of dye coupling in these slices strongly suggests the existence of cell compartments in the postnatal SVZa.
Assuntos
Animais Recém-Nascidos/fisiologia , Ventrículos Cerebrais/fisiologia , Junções Comunicantes/fisiologia , Animais , Cálcio/metabolismo , Carbenoxolona/farmacologia , Dextranos/antagonistas & inibidores , Dextranos/farmacocinética , Difusão/efeitos dos fármacos , Corantes Fluorescentes/farmacocinética , Halotano/farmacologia , Técnicas In Vitro , Membranas Intracelulares/metabolismo , Isoquinolinas/antagonistas & inibidores , Isoquinolinas/farmacocinética , Camundongos , Ratos , Ratos Wistar , Rodaminas/antagonistas & inibidores , Rodaminas/farmacocinética , Desacopladores/farmacologiaRESUMO
Lesion of the anteroventral third-ventricle region (AV3VX) reduced saline consumption. Salt loading in AV3VX rats resulted in reduced but not completely abolished c-fos expression in the supraoptic and paraventricular nuclei. Intrinsic osmosensitivity of the magnocellular neurons, or input from other brain areas, such as the subfornical and median preoptic nuclei, may account for this residual c-fos expression. These regions showed c-fos expression following salt loading.