Effect of moringa oleifera lam. leaf extract against aluminium chloride induced hippocampal histology and serum enzyme activities in adult Wistar rats / Efecto del extracto de hoja de Moringa Olifera Lam. en la histología del hipocampo y la actividad enzimática en el suero de ratas Wistar adultas expuestas a cloruro de aluminio

Introduction: Aluminium, a ubiquitous metal implicated in some neurodegenerative diseases is linked to activation of free oxygen species. The antioxidant-rich plants, Moringa oleifera (MO) is reported to protect against Aluminium activities. This study investigated the actions of MO leaf extract (MOLE) against Aluminium chloride (AlCl3)- induced hippocampal cellular changes and serum levels of alkaline phosphatase (ALP), aspartate transaminase (AST) and alanine transaminase (ALT) in adult Wistar rats.Materials and Methods: Thirty Wistar rats weighing between 150 g and 220 g were grouped (n=5) into; 1-control (5 mL/kg distilled water), 2-AlCl3 (100 mg/kg), 3-low dose MOLE (250 mg/kg), 4-high dose MOLE (1,000 mg/kg), 5-concurrent AlCl3 and low dose MOLE, and 6-concurrent AlCl3 and high dose MOLE. All administrations were by oral gavages for 21 days. On day 22, following deep anaesthesia and cardiac puncture, blood was obtained for serum enzyme analysis, and the brain perfusion fixed, harvested and processed for histological study.Results: Results showed significantly (p < 0.05) higher ALP level in the AlCl3 group compared with the control, as well as the other test groups. However, there was no significant (p > 0.05) AST and ALT levels. The hippocampal CA3 of the AlCl3 group showed hypertrophic cells, with some of the cells having karyorrhectic features. The concurrent AlCl3 and low and high doses, MOLE groups showed less of these adverse features.Conclusion: These results suggest that MOLE may protect enzymatic activities against Aluminium chloride. However, its action on hippocampus is still subject to further investigation.

Introducción: El aluminio, un metal presente en diversos lugares implicado en algunas enfermedades neurodegenerativas, está relacionado con la activación de especies reactivas de oxígeno. Se informa que las plantas ricas en antioxidantes, Moringa oleifera (MO) protegen contra la acción del aluminio. Este estudio investigó las acciones del extracto de hoja de MO (MOLE) en los cambios celulares del hipocampo inducidos por el cloruro de aluminio (AlCl3) y los niveles séricos de fosfatasa alcalina (ALP), aspartato transaminasa (AST) y alanina transaminasa (ALT) en ratas Wistar adultas.Materiales y métodos: SE utilizaron treinta ratas Wistar divididas en 5 grupos, los animales pesaban entre 150 gy 220 g; 1 control (5 ml / kg de agua destilada), 2-AlCl3 (100 mg / kg), 3 MOLE de dosis baja (250 mg / kg), 4 MOLE de dosis alta (1000 mg / kg), 5 AlCl3 concurrente y MOLE de dosis baja, y MOLE 6-concurrente y MOLE de dosis alta. Todas las administraciones fueron por sonda oral durante 21 días. El día 22, después de la anestesia profunda y la punción cardíaca, se obtuvo sangre para el análisis de las enzimas séricas y la perfusión cerebral se fijó, recogió y procesó para el estudio histológico.Resultados: Los resultados mostraron un nivel de ALP significativamente (p <0.05) más alto en el grupo AlCl3 en comparación con el control, así como en los otros grupos de prueba. Sin embargo, no hubo niveles significativos (p> 0.05) de AST y ALT. El hipocampo CA3 del grupo AlCl3 mostró células hipertróficas, y algunas de las células tenían características cariorrecticas. Los grupos de AlCl3 concurrentes y dosis bajas y altas, MOLE mostraron menos de estas características adversas.Conclusión: Estos resultados sugieren que MOLE puede proteger las actividades enzimáticas contra el cloruro de aluminio. Sin embargo, su acción sobre el hipocampo aún está sujeta a más investigaciones.

Characterization of hippocampal histomorphology following R. vomitoria root extract treatment / Caracterización de la histomorfología del hipocampo después del tratamiento con extracto de la raíz de R. vomitoria

Rauwolfia vomitoria Afzel. is an antipsychotic plant used by several African communities in the management of psychiatric conditions with good outcomes. Concerns about its dosages on brain activity lead to this investigation of its action on the hippocampal microstructure.Twenty-four adult male Wistar rats of average weight 200 g, were assigned into four groups (n = 6): control; 200, 300 and 400 mg/kg body weight of RVroot bark extract, respectively. The administration was once daily, and orally for seven days. Daily observation of the animals was done till on day eight when they were sacrificed after deep anaesthesia. Each brain was processed for histology and immunohistochemical studies. Animals in the 200, 300 and 400 mg/kg RV groups appeared generally dull and drowsy, and barely fed. Their hippocampal histology showed neuronal atrophy and karyorrhexis, with no difference in cell count, although the pyramidal cell numbers decreased in the 300 and 400 mg/kg RV groups. Neuron-specific enolase decreased in the 400 mg/kg RV group, while neurofilament decreased in all test groups. Glial fibrillary acidic protein expression and density increased in the 200 and 300 mg/kg RV groups, but not the 400 mg/kg RV group, all compared with the control group.The given doses of RV root bark extractin adult Wistar rats showed sedative activities with hippocampal histopathological changes, which may not be reversible, thereby leading to the hippocampal functional deficit.

Introducción: Rauwolfia vomitoria (RV) Afzel es una planta antipsicótica utilizada por varias comunidades africanas en el tratamiento de enfermedades psiquiátricas con buenos resultados. Las preocupaciones sobre sus efecto sobre la actividad cerebral conducen a esta investigación de su acción sobre la microestructura del hipocampo.Materiales y métodos: Se asignaron veinticuatro ratas Wistar macho adultas de un peso medio de 200 g, en cuatro grupos (n = 6): control; 200, 300 y 400 mg / kg de peso corporal de extracto de corteza de raíz de RV, respectivamente. La administración fue una vez al día y por vía oral durante siete días. Se realizó una observación diaria de los animales hasta el día ocho, cuando fueron sacrificados después de una anestesia profunda. Cada cerebro fue procesado para estudios histológicos e inmunohistoquímicos.Resultados: Los animales en los grupos de RV de 200, 300 y 400 mg / kg parecían generalmente apagados y somnolientos, y apenas alimentados. Su histología hipocampal mostró atrofia neuronal y cariorrexis, sin diferencia en el recuento celular, aunque el número de células piramidales disminuyó en los grupos de RV de 300 y 400 mg / kg. La enolasa específica de neuronas disminuyó en el grupo de RV de 400 mg / kg, mientras que el neurofilamento disminuyó en todos los grupos de prueba. La expresión y densidad de la proteína fibrilar ácida glial aumentó en los grupos de RV de 200 y 300 mg / kg, pero no en el grupo de RV de 400 mg / kg, todos en comparación con el grupo de control.Conclusión: Las dosis administradas de extracto de corteza de raíz de RV en ratas Wistar adultas mostraron actividades sedantes, con cambios histopatológicos del hipocampo, que pueden no ser reversibles, lo que conduce al déficit funcional del hipocampo.

Structural Volume of Hippocampus and Alzheimers Disease

RESUMO Pesquisas recentes demonstram que o hipocampo apresenta uma redução de volume no final da idade adulta, mantendo uma estreita relação com o declínio cognitivo. A aquisição da imagem por diversos métodos de medição de volume nos leva a encontrar na ressonância magnética o método de destaque, pois permite quantificar o volume de determinadas estruturas cerebrais utilizando a reconstrução computadorizada tridimensional das imagens obtidas. OBJETIVOS Confirmar a existência de diferenças entre o volume hipocampal e o declínio cognitivo leve, doença de Alzheimer e cognição normal. MÉTODOS Levantamento bibliográfico de estudos que apresentassem dados referentes aos distúrbios da doença de Alzheimer, alterações macroscópicas cerebrais detectadas com softwares na ressonância magnética e segmentação. Foram adicionados estudos apenas da medição volumétrica do hipocampo, objetivando-se chegar a valores que possam estabelecer uma correlação do menor valor estrutural hipocampal e risco de desenvolvimento da doença. RESULTADOS Um total de 1.070 indivíduos foi analisado em seis estudos clínicos, demonstrando a relação da diminuição do hipocampo na neuroimagem, correlacionado com o comprometimento cognitivo leve e doença de Alzheimer. CONCLUSÕES O desenvolvimento de um valor padrão para esse fim seria bastante útil na coleta de dados, permitindo melhor compreensão de algumas alterações que podem ocorrer na cognição, determinar valores prognósticos e até, em um futuro próximo, fator de risco imagiológico para a doença.

Caracterização de um modelo de paralisia cerebral em ratos: cognição e estrutura do hipocampo e amígdala / Characterization of a model of cerebral palsy in rats: cognition and structureof the hippocampus and amygdala

FUNDAMENTO: A paralisia cerebral (PC) é caracterizada por distúrbios do movimento e da postura, que podem estar associados a déficits cognitivos. Tais comprometimentos são atribuídos a lesões não progressivas ao encéfalo em desenvolvimento. No âmbito experimental, modelos animais dessa condição clínica capazes de reproduzir o fenótipo e as alterações estruturais vistas em humanos são escassos. OBJETICO: Investigar as repercussões da indução de um modelo de PC sobre a função cognitiva e estrutura do hipocampo e amígdala em ratos Wistar. MÉTODOS: Dois grupos experimentais foram utilizados: 1) Controle - filhotes de ratas injetadas com solução salina durante a gestação (n=8) e 2) Paralisia cerebral - filhotes de ratas injetadas com Lipopolissacarídeo (LPS) durante a gestação (n=8), submetidos à anóxia perinatal e restrição sensório-motora durante 30 dias. A memória espacial dos animais foi avaliada pela tarefa de reconhecimento da localização de objetos, enquanto o comportamento do tipo ansioso foi verificado pelo teste de labirinto em cruz elevado. Após a avaliação comportamental, os animais foram eutanasiados e os encéfalos dissecados para posterior processamento histológico. RESULTADOS: O grupo PC apresentou déficits de memória espacial e uma redução do número de neurônios granulares no giro denteado. Entretanto o comportamento do tipo ansioso e a histologia do núcleo central e complexo basolateral da amígdala foram semelhantes entre os grupos. CONCLUSÃO: Como observado em parte dos pacientes com PC, este modelo experimental prejudica a memória dependente do hipocampo. Entretanto, a combinação de intervenções não alterou a ansiedade e estrutura da amígdala.

BASIS: Cerebral palsy (CP) is a disorder of movement and posture, which may be associated with cognitive impairments. Such clinical condition is caused by non progressive injuries ocurred during the brain development. In the experimental context, animal models of this condition that can reproduce the phenotype and the structural changes seen in humans are scarce. OBJECTIVE: The present study investigated cognitive function and hippocampus and amygdala structure in rats submitted to a CP model. METHODS: Two experimental groups were used: 1) Control - offspring of rats injected with saline during pregnancy (n = 8) and 2) Cerebral Palsy - offspring of rats injected with lipopolysaccharide (LPS) during pregnancy (n = 8), submitted to perinatal anoxia and sensorimotor restriction for 30 days. The spatial memory was evaluated by the object-placement recog- nition task and anxiety like-behavior by elevated plus maze test. After the behavioral assessment, animals were euthanized and brains dissected for histological processing. RESULTS: The PC group showed spatial memory deficits and a reduction of granule neurons in the dentate gyrus. However, the anxiety like-behavior and the number of neurons in central nucleus and basolateral complex of the amygdala were similar between studied groups. CONCLUSION: This animal model affects the hippocampus dependent memory, a deficit seen in part of CP patients. However, the interventions used did not alter the anxiety like-behavior and amygdala structure.

Microglia and neurons in the hippocampus of migratory sandpipers

The semipalmated sandpiper Calidris pusilla and the spotted sandpiper Actitis macularia are long- and short-distance migrants, respectively. C. pusilla breeds in the sub-arctic and mid-arctic tundra of Canada and Alaska and winters on the north and east coasts of South America. A. macularia breeds in a broad distribution across most of North America from the treeline to the southern United States. It winters in the southern United States, and Central and South America. The autumn migration route of C. pusilla includes a non-stop flight over the Atlantic Ocean, whereas autumn route of A. macularia is largely over land. Because of this difference in their migratory paths and the visuo-spatial recognition tasks involved, we hypothesized that hippocampal volume and neuronal and glial numbers would differ between these two species. A. macularia did not differ from C. pusilla in the total number of hippocampal neurons, but the species had a larger hippocampal formation and more hippocampal microglia. It remains to be investigated whether these differences indicate interspecies differences or neural specializations associated with different strategies of orientation and navigation.

Sensory evaluation of dairy supplements enriched with reduced iron, ferrous sulfate or ferrous fumarate / Evaluación sensorial de suplementos lácteos enriquecidos con hierro reducido, sulfato ferroso o fumarato ferroso

Objective. To determine the degree of liking of the Oportunidades programme dietary supplements (DS) -purees and beverages- added with different iron salts (IS): reduced iron (RI), ferrous sulphate (FS) or ferrous fumarate (FF) during 24 weeks of storage. Materials and methods. The DS were evaluated through a hedonic scale for aroma, flavour and colour attributes; at time zero and every eight weeks, each panel member evaluated three DS with same flavour and presentation but different IS. Seventy women participated as panel members. Results. The chocolate and banana DS exhibited a change in preference by colour and flavour due to storage. DS with FS or RI showed the least preference by flavour and colour in the context of the three IS considered. The chocolate and neutral DS enriched with FS changed their colour and flavour. Conclusion. DS were, in general, well-liked; nonetheless, for purees enriched with FS and for beverages enriched with RI, the less-liked attributes were colour and flavour.

Objetivo. Determinar el nivel de agrado de los suplementos alimenticios (SA) (papillas y bebidas) del Programa Oportunidades, adicionados con diferentes sales de hierro (SH): hierro reducido (HR), sulfato ferroso (SF) o fumarato ferroso (FF), durante 24 semanas de almacenamiento. Material y métodos. Se evaluaron mediante una escala hedónica los atributos olor, sabor y color; a tiempo cero y cada ocho semanas, cada juez evaluó tres suplementos, mismo sabor, presentación y diferente SH. Participaron 70 mujeres. Resultados. Los SA sabor chocolate y plátano presentaron modificación del agrado por color y sabor durante el almacenamiento. Los SA con SF o HR presentaron el menor agrado para sabor y olor por efecto de las SH. En los SA sabor chocolate y natural adicionados con SF se afectó el color y el sabor. Conclusión. Los SA en general presentaron agrado; sin embargo, en las papillas adicionadas con SF y las bebidas con HR los atributos limitantes fueron color y sabor.

Longitudinal brain volumetric changes during one year in non-elderly healthy adults: a voxel-based morphometry study

Previous cross-sectional magnetic resonance imaging (MRI) studies of healthy aging in young adults have indicated the presence of significant inverse correlations between age and gray matter volumes, although not homogeneously across all brain regions. However, such cross-sectional studies have important limitations and there is a scarcity of detailed longitudinal MRI studies with repeated measures obtained in the same individuals in order to investigate regional gray matter changes during short periods of time in non-elderly healthy adults. In the present study, 52 healthy young adults aged 18 to 50 years (27 males and 25 females) were followed with repeated MRI acquisitions over approximately 15 months. Gray matter volumes were compared between the two times using voxel-based morphometry, with the prediction that volume changes would be detectable in the frontal lobe, temporal neocortex and hippocampus. Voxel-wise analyses showed significant (P < 0.05, family-wise error corrected) relative volume reductions of gray matter in two small foci located in the right orbitofrontal cortex and left hippocampus. Separate comparisons for males and females showed bilateral gray matter relative reductions in the orbitofrontal cortex over time only in males. We conclude that, in non-elderly healthy adults, subtle gray matter volume alterations are detectable after short periods of time. This underscores the dynamic nature of gray matter changes in the brain during adult life, with regional volume reductions being detectable in brain regions that are relevant to cognitive and emotional processes.

Postnatal development of the hippocampal formation in male albino rats: histological, immunohistochemical, and morphometric studies

The hippocampal formation plays a demonstrated role in learning and memory, and it is selectively impaired in many developmental brain diseases. Developmental studies on this brain area are important for understanding the neurodevelopmental disorders. To study the postnatal development of the hippocampal formation. Five male albino rats from the following postnatal ages PO, P7, P14, and P90 were studied by histological, immunohistochemical, and morphometric methods. The general architecture of the hippocampus proper with its polymorphic, pyramidal, and molecular layers was present at PO, whereas the details of the adult structure appeared at P14. In the dentate gyrus, distinct lamination appeared at P7 and its maturation continued with the production of neurons at the interhilar zone that peaked at P14. Astrocytes increased in size and staining affinity for glial filaments, and acquired a stellate shape with age. Microtubule-associated protein 2 immunoreactivity was observed in the perikarya at PO and in the sprouting dendrites at P7 and P14. At P90, the dendrites occupied the whole thickness of the molecular layer. Number of light pyramidal neurons decreased, whereas that of dark neurons increased from PO to P90. Furthermore, the number of granule cell layers increased concomitantly with the increase in thickness of the molecular and polymorphic layers of both the hippocampus proper and the dentate gyrus. The important sequences of events in the growth and maturation of the hippocampal formation in male albino rat occurred in the first 2 postnatal weeks

Immunolocalization of estrogen receptor alpha in adult female rat hippocampus / Inmunolocalización del receptor de estrógeno alfa en el hipocampo de rata hembra adulta

The present study was planned to demonstrate the detailed immunoreactive (IR) distribution pattern of estrogen receptors (ER) in hippocampus of 15 female rats, adult, female Wistar rats in estrous phase. 30 µm thick setions of hippocampal region fixed (4 percent buffered paraformaldehyde) were obtained with cryostat. The sections were processed free- floating for immunolocalization of ER using, mouse monoclonal anti-ER-a antibody with PAP technique. The results showed presence of ER immunoreactive neurons in all the subfields of hippocampus with some variations. In cornua ammonis (CA) maximum ER positive (+ve) neurons were localized in CA3 region. Layer analysis showed maximum localization in the stratum oriens (SO) region. In other subfields and layers of CA the IR neurons were comparatively less in number. The morphological characters of all ER +ve neurons showed them to be interneurons both in CA as well as in Dentate gyrus (DG).

El estudio fue diseñado para demostrar el patrón de distribución inmunorreactivo (IR) detallado de los receptores estrogénicos (RE) en el hipocampo de 15 ratas Wistar, hembras, adultas, en fase de estro. Fueron obtenidas secciones 30 µm de grosor con un crióstato, de la región del hipocampo fijadas por perfusión (4 por ciento de paraformaldehído tamponado). Las secciones fueron procesadas, por libre flotación, para la inmunolocalización de RE utilizando anticuerpo monoclonal de ratón anti-ER-a con la técnica de PAP. Los resultados mostraron la presencia de neuronas inmunorreactivas ER en todos los subcampos del hipocampo con algunas variaciones. En el cuerno ventral (CA) la mayor zona RE positiva (+ ve) de las neuronas se localizaron en la región CA3. El análisis de las capas mostró la localización máxima en la región del estrato oriens (SO). En otros subcampos y capas de la CA las neuronas IR fueron comparativamente menores en número. Las características morfológicas de todas las neuronas RE + ve resultaron ser interneuronas tanto en el CA como en el giro dentado (DG).

Total neuron numbers in CA1-4 sectors of the dog hippocampus.

Background & objectives: Early reports addressed morphological asymmetry in the cross-sectional width of the rat hippocampus. The present study was aimed at counting total number of neurons in CA1-4 sectors and the subiculum of the dog hippocampus as well as investigating possible left /right and male/female asymmetry. Methods: Adult mongrel dogs (8 female and 5 male) were assessed by the right and left pawedness and sacrificed by exsanguinations. In each hippocampus dissected, the total neuron numbers of CAs and subiculum were estimated by the physical fractioning method. Results: Significant hemispheric asymmetries were found in the number of pyramidal cells of CA1, CA3/2, CA4 and the subiculum. Sex difference was also found in the subiculum, in favour of the males. Interpretation & conclusion: Our study indicated a left dominant asymmetry in males and right dominancy in females as well as no functional asymmetry in specific regions of the dog hippocampus. Further investigations are necessary to verify the hypothesis that hippocampal morphological asymmetries in normal subjects are functionally related in memory or in cognitive skills.

Effect of mobile phone microwaves on fetal period of BALB/ c mice in histological characteristics of hippocampus and learning behaviors

The possible risks of radio-frequency electromagnetic fields [EMF] for the living organisms and human body are a growing concern for our society. In this study, we examined the possibility of changes in working memory and hippocampal histological characteristics effects in mice brain following whole body exposure to microwave radiation. During gestation period, we exposed mice for 4 hr to Global system for mobile communications [GSM], Specific Absorption Rate [SAR] of 200 mW/kg. Pregnant control mice were sham-exposed or free in a cage without further restraining. Three month after exposure, animals were prepared for behavioral [Radial Arm Maze [RAM] and Morris Water Maze [MWM]] and histological studies. The showed that microwave exposed mice were slower than sham, and control in finding the platform. Analyses of error rates in RAM and MWM performance revealed significant differences which emphasize the effect of acute exposure to pulsed microwaves in deficit of spatial reference memory in the mice. However in this study exposed group didn't show any statistically significant loss of hippocampal CA1, CA3 neurons versus controls or sham. We conclude that there is evidence from the current study that exposure to MW radiation under parameters examined caused decrements in the ability of mice to learn the spatial memory task

Esclerosis temporal mesial: paradigma de la epilepsia de resolución quirúrgica / Mesial temporal sclerosis: paradigm of surgically treatable epilepsy

Objetivo. Describir la esclerosis temporal mesial (ETM) es sus aspectos anatómicos, fisiopatológico, clínico, imagenológico, neurofisiológico, neuropsicológico y quirúrgico; y su relación con la epilepsia de resolución quirúrgica. Luego analizar estadísticamente nuestra casuística y resultados. Materiales y métodos. De los 469 (115 adultos y 354 niños) pacientes intervenidos quirúrgicamente por presentar epilepsia entre los años 1989-2007 en el Hospital Dr. Juan P. Garraham, FLENI, Hospital Dr. Cosme Argerich y Hospital Prof. Dr. Rodolfo Rossi, se analizar 91 pacientes (19.4%) con el diagnóstico de ETM; 38 de los cuales (41.75%) son niños y 53 (58.25%) adultos. Resultados. Los resultados son evaluados mediante el score de Engel. Aplicando esta clasificación, nuestra población tiene la siguiente distribución; 69 pacientes (75.8%) se encuentran en clase IA de Engel, de ellos 36 son niños (52.2%) y 33 adultos (47.8%); 4 pacientes adultos se encuentran en Engel IB (4.4%), 3 en Engel IC (3.3%), 1 adulto en Engel ID (1.1%), 4 adultos en Engel IIA (4.4%), 5 adultos en Engel IIB (5.5%) y 3 pacientes en Engel IVA (3.3%) de ellos 1 niño a quien posteriormente se le implantó un estimulador del nervio vago y los 2 restantes adultos. Un paciente adulto se suicidó luego de un año de la cirugía (en clase IA de Engel). Un paciente se encuentra durante su primer año postoperatorio por lo cual no puede ser incluido aún en la estadística de resultados. Conclusión. La ETM es el paradigma de la epilepsia refractaria en al población adulta y la causa de un porcentaje significativo de pacientes pediátricos sometidos a cirugía. La evolución prequirúrgica debe ser exhaustiva para lograr la selección del paciente. La resección quirúrgica debe ser realizada con la mayor selectividad posible. El diagnóstico y tratamiento precoz permite lograr un alto índice de curación.

Exposure to chronic noise reduces the volume of hippocampal subregions in rats

The hippocampal circuit integrity is crucial for learning and memory. Despite the existing reports on hippocampal_dependent memory impairment due to noise stress, there are only a few studies on the effect of noise stress on anatomical structure of hippocampus. The present study is aimed to investigate the likely effects of chronic noise exposure on the volume of rat hippocampus. Two-month male Wistar rats were randomly divided into three groups [n=10 in each group]. In the control group rats were maintained under standard laboratory conditions [150 days]. In the noise-exposed group: Rats were exposed to 40 dB unmodulated sinosoidal noise with a frequency of 1100 Hz for 20 mins, three times per day for 90 days. The recovery group rats were exposed to noise for 90 days and allowed to survive without further treatment until the day of sacrifice [180th day]. The right hemispheres were selected for stereological study. Twenty five mm thick sections were cut along the entire extent of the hippocampus. Using systematic uniformly random sampling, one section from every twenty sections was analyzed. Volume estimation was performed using Cavalieri principle. Statistical analysis revealed that noise stress induces a significant reduction in volume of all layers of hippocampal subdivisions, except CA1 hippocampal field. In addition, we found that rats which were allowed to recover from noise displayed larger volume of dentate gyrus and CA3 hippocampal field in comparison to noise-exposed rats. Reduced volume of hippocampal layers most probably reflects structural alterations in the neurites of related neurons. These results provide a neuroanatomical basis that may be relevant to the reported memory disturbances in human and animals following noise stress

Anatomia microcirúrgica do hipocampo na Amígdalo-hipocampectomia seletiva sob a perspectiva da técnica de Niemeyer e método pré-operatório para maximizar a corticotomia / Hippocampal microsurgical anatomy regarding the selective amygdalohippocampectomy in the Niemeyer’s technique perspective and preoperative method to maximize the corticotomy

O conhecimento da anatomia microcirúrgica do hipocampo tem importância fundamental na cirurgia da epilepsia do lobo temporal. Uma das técnicas mais utilizadas na cirurgia da epilepsia é a técnica de Niemeyer. OBJETIVO: Descrever em detalhes a anatomia do hipocampo e mostrar uma técnica na qual pontos de referências anatômicos pré-operatórios visualizados na RNM são usados para guiar a corticotomia. MÉTODO: Foram utilizados 20 hemisférios cerebrais e 8 cadáveres para dissecções anatômicas microcirúrgicas do lobo temporal e hipocampo para identificação e descrição das principais estruturas do hipocampo. Foram estudados prospectivamente 32 pacientes com epilepsia do lobo temporal refratários ao tratamento clínico submetidos a amígdalo-hipocampectomia seletiva pela técnica de Niemeyer três parâmetros anatômicos foram mensurados na RNM pré operatória e transferidos para o ato cirúrgico. RESULTADOS: O hipocampo foi dividido em cabeça, corpo e cauda e sua anatomia microcirúrgica descrita em detalhes. As medidas adquiridas são apresentadas e discutidas. CONCLUSÃO: A complexa anatomia do hipocampo pode ser entendida de uma forma tridimensional durante dissecções microcirúrgicas. As medidas pré-operatórias mostraram-se guias anatômicos úteis para corticotomia na técnica de Niemeyer.

The deep knowledge of hippocampal microsurgical anatomy is paramount in epilepsy surgery. One of the most used techniques is those proposed by Niemeyer. PURPOSE: To describe the hippocampal anatomy in details and to present a technique which preoperative anatomical points in MRI are identified to guide the corticotomy. METHOD: Microsurgical dissections were performed in twenty brain hemispheres and eight cadaveric heads to identify temporal lobe and hippocampus structures. Thirty two patients with drug-resistent temporal lobe epilepsy underwent a selective amygdalohippocampectomy with Niemeyer’s technique being measured three preoperative MRI preoperative distances to guide the corticotomy. RESULTS: The hippocampus was divided in head, body and tail and its microsurgical anatomy described in details. The MRI measurements are presented and discussed. CONCLUSION: The knowledge of the complex anatomy of the hippocampus can be achieved in a three-dimensional way during microsurgical dissections not. The preoperative MRI measurement is a reasonable guide to perform temporal corticotomy in Niemeyer’s techinique.

As bases neuroanatômicas do comportamento: histórico e contribuições recentes / Neuroanatomical basis of behavior: history and recent contributions

Tendo em vista as mais recentes contribuições, as áreas corticais límbicas - originalmente denominadas em conjunto de grande lobo límbico -, além dos giros do cíngulo e parahipocampal, são constituídas pelas regiões mais posteriores do córtex fronto-orbitário e pelo córtex insular. Em contraposição ao restante do córtex cerebral, que se projeta sobre os gânglios da base (particularmente sobre as porções mais dorsais e mais extensas do striatum, constituídas fundamentalmente pelo núcleo caudado e pelo putame), as áreas corticais límbicas se caracterizam por se projetarem principalmente sobre o hipotálamo e também sobre a porção mais ventral do striatum (principalmente sobre o núcleo accumbens). Uma vez que todo o striatum se projeta para o globo pálido - e este para o tálamo, que se projeta para o córtex cerebral, constituindo-se, assim, circuitos córtico-subcorticais reentrantes -, tem-se que, enquanto as alças relacionadas com o striatum e o pallidum dorsais são responsáveis por atividades e rotinas motoras, as alças relacionadas com o striatum e o pallidum ventrais caracterizam circuitos córtico-subcorticais reentrantes e segregados que se relacionam particularmente com funções comportamentais. A amígdala estendida (amígdala centromedial, componente dorsal ou estria terminal, componente ventral e núcleo da estria terminal), por sua vez, também recebe aferências de todas as áreas corticais límbicas, é particularmente modulada pelas áreas corticais pré-frontais e, ao invés de se projetar sobre o striatum, projeta-se diretamente sobre o hipotálamo e o tronco encefálico. Ao receber também conexões diretas do tálamo, a amígdala estendida pode ainda desencadear respostas principalmente autonômicas, de forma inespecífica, porém rápida, através da ativação de centros do tronco encefálico. Os sistemas macro-anatômicos fronto-basais, estriatal-palidal ventral e amígdala estendida, em conjunto com o núcleo basal de Meynert e com o sistema septo-banda...

Considering the most recent contributions, the limbic cortical areas, originally known as the greater limbic lobe, besides the cingulated and the parahippocampal gyri also includes the insula and the posterior orbital cortex. In contrast to the nonlimbic cortical areas that project to the basal ganglia (particularly over the dorsal aspects of the striatum, constituted by the caudate nucleus and by the putamen), the limbic cortical areas are characterized by projecting to the hypothalamus and also to the ventral striatum (particularly to the nucleus accumbens). Once all the striatum projects to the globus pallidus which projects to the thalamus and then to the cortex, generating cortical-subcortical reentrant circuits, while the dorsal striatum and pallidum related cortico-subcortical loops are involved with motor activities, the ventral cortical-striatal-pallidal system is particularly related with behavior functions. The extended amygdala (central medial amygdala, stria terminalis or dorsal component, ventral component, and bed nucleus of stria terminalis) receives inputs primarily from the limbic cortical areas, is particularly modulated by the prefrontal cortex, and receives also direct connections from the thalamus that enables the amygdala to generate nonspecific and quick responses through its projections to the hypothalamus and to the brainstem. The ventral striatal-pallidal and the extended amygdala are then two basal forebrain macro-anatomical systems, that together with the basal nucleus of Meynert and with the septal-diagonal band system, constitute the main structures that are particularly connected with the limbic cortical areas, and that altogether project to the hypothalamus and to the brainstem which give rise to the autonomic, endocrine and somatosensory components of the emotional experiences, and that regulate the basic activities of drinking, eating, and related to the sexual behavior.

Variations in the origin and contributions of arteries supplying the human hippocampus: an anatomical study

Variations in the arterial supply in the human brain are not uncommon. Of particular interest is that of the hippocampus. Knowledge of the vascular anatomy is a key to the surgical treatment of pathologies in this region. The aim of the work is a detailed description of the variations and contribution of the anterior choroidal artery and the branches of the posterior cerebral artery to the supply of the hippocampus and comparing the results with previous studies. Formalin-fixed brains from 15 adult cadavers [30 hemispheres] were examined using a magnifying lens. The hippocampus is identified, and the arteries that are in the vicinity to hippocampus were carefully dissected and studied. The anterior choroidal artery [AchA], and the lateral posterior choroidal arteries [LPChAs] were present in 100% of the specimens examined. AChA anastomosed with the anterior branches of LPChA in 31% of specimens. The hippocampal artery, a branch of the posterior cerebral artery, was present in 82.8% of specimen. The anterior and middle temporal arteries were present in 80% of hemispheres. ACA has the most constant origin, course and distribution. It supplied the rstral and middle portions of the hippocampus and in the absence of the hippocampal arterial branches of the posterior cerebral artery [PCA], AchA supplied the major portion of the hippocampus. The branches, mainly from P-2 A and P-2P segments, of the PCA supplied the middle and posterior portions of the hippocampus. Variations in their origin from different segments were noted. The major branches were: the LPChAs, the hippocampal arteu, the anterior and middle temporal arteries. The common temporal artery did not contribute to the arterial supply of the hippocampus

Role of gamma-aminobutyric acid B (GABA B) receptors in the regulation of kainic acid-induced cell death in mouse hippocampus

Kainic acid (KA) is well-known as an excitatory, neurotoxic substance. In mice, KA administered intracerebroventricularly (i.c.v.) lead to morphological damage of hippocampus expecially concentrated on the CA3 pyramidal neurons. In the present study, the possible role of gamma-aminobutyric acid B (GABA B) receptors in hippocampal cell death induced by KA (0.1 microgram) administered i.c.v. was examined. 5-Aminovaleric acid (5-AV; GABA B receptors antagonist, 20 microgram) reduced KA-induced CA3 pyramidal cell death. KA increased the phosphorylated extracellular signal-regulated kinase (p-ERK) and Ca2+ /calmodulin-dependent protein kinase II (p-CaMK II) immunoreactivities (IRs) 30 min after KA treatment, and c-Fos, c-Jun IR 2 h, and glial fibrillary acidic protein (GFAP), complement receptor type 3 (OX-42) IR 1 day in hippocampal area in KA-injected mice. 5-AV attenuated KA-induced p-CaMK II, GFAP and OX-42 IR in the hippocampal CA3 region. These results suggest that p-CaMK II may play as an important regulator on hippocampal cell death induced by KA administered i.c.v. in mice. Activated astrocytes, which was presented by GFAP IR, and activated microglia, which was presented by the OX-42 IR, may be a good indicator for measuring the cell death in hippocampal regions by KA excitotoxicity. Furthermore, it showed that GABA B receptors appear to be involved in hippocampal CA3 pyramidal cell death induced by KA administered i.c.v. in mice.

Sistema límbico: estudio in vivo de los hipocampos y de los núcleos amigdaloideos mediante resonancia magnética / In vivo measurements of amygdaloid and hippocampal volume by MRI

Con el propósito de estudiar in vivo dos estructuras grises que son fundamentales en el sistema límbico, determinando la eventual existencia de diferencias ligadas a la edad y al sexo, efectuamos un examen de resonancia magnética cerebral a ciento nueve pacientes, mediante un protocolo estandarizado. Todos ellos presentaron examen clínico y neuropsiquiátrico normal y un mapeo cerebral sin evidencias electrofisiológicas de patología. En ninguno había antecedentes de convulsiones ni de ingesta prolongada de glucocorticoides. Los estudios fueron vistos consecutiva o similtáneamente por ambos autores, tras lo cual, en una consola de trabajo y de idéntico modo, se efectuaron las mediciones de volumen de las estructuras grises mencionadas: el hipocampo y el núcleo amigdaloideo; para lo cual el reformateo axial oblícuo de secuencias 3D que ponderaron T1 fue fundamental. Los resultados se tabularon teniendo en cuenta edad, sexo y los volúmenes obtenidos, y fueron analizados mediante regresión simple sin transformar variables, tomando como independiente a la edad, y como variables dependientes al volumen amigdaloideo e hipocámpico en varones y mujeres. Se obtuvieron regresiones significativas relacionando la edad con la amígdala, siendo estos análisis diferentes en varones y mujeres. Comparando las rectas de regresión de ambos grupos se obtuvieron estadísticas que confirman las diferencias. No se obtuvo pendiente en el caso del hipocampo en mujeres. Respecto del hipocampo en varones la pendiente y, por lógica, el ajuste, tuvieron poca significación

Unión P[3H]-QNB al receptor muscarínico humano en presencia de diferentes buffers / Union of P[3H]-QNB at muscarinic receptor human in presence of different buffers

Se estudio el perfil de unión de [3H]-Benzilato de Quinuclidinilo ([3H]-QNB) al receptor colinérgico muscarínico (RCM) de corteza frontal (CFH) e hipocampo humano (HPH) en presencia de diferentes buffers. Cuando las fracciones de CFH se prepararon y ensayaron en Buffers TRIS, FOSFATO o HEPES, la unión fue compatible con una discreta cooperatividad homotrópica positiva (coeficiente de Hill: 1.10-1.37). Cuando los ensayos de unión de [3H]-QNB al RCM de CFH se realizaron con buffers imidazol o citrato, la cinética resultó hiperbólica simple. El fenómeno de cooperatividad positiva se encontró en HPH mediante el uso de buffer fosfato, pero no con iris e imidazole. El uso de borato como buffer para preparar y ensayar las fracciones de CFH o HPH indujo una cinética compatible con cooperatividad homotrópica negativa o heterogeneidad, con 32-36 por ciento de sitios de alta afinidad y 64-68 por ciento de baja afinidad. El efecto inhibitorio de la fuerza iónica sobre la unión de [3H]-QNB fue similar en borato, imidazol, tris, herpes y citrato. A altas concentraciones, el efecto del buffer fosfato fue también inhibitorio, sin embargo, a bajas concentraciones, se observó un 10 por ciento de aumento en la unión. Estos resultados sugieren que la unión de [3H]-QNB al RCM humano es compleja y dependiente de las condiciones del medio.