El término cuerpo amigdaloide en la terminología médica / The term amygdaloid body in medical terminology

RESUMEN: En terminología médica el término amígdala cerebral es utilizado para denominar a la estructura que según la Terminologia Neuroanatomica y Terminologia Anatomica se conoce como cuerpo amigadaloide, la cual está constituida por diversos núcleos y es responsable de las emociones, el comportamiento, regulación de la ansiedad, la agresión, el miedo, la memoria emocional, la cognición social y las respuestas al estrés. Siendo la amígdala cerebral una estructura tan importante el objetivo de este estudio fue: analizar el significado del término amígdala cerebral en la Terminologia Neuronatomica y en la Terminologia Anatomica y contrastar si el origen de sus raíces greco latinas concuerdan con la función de esta estructura acorde con los requerimientos de la FIPAT. Para ello se consultó los diccionarios de la Lengua Española, Diccionario DGE Griego Español, Diccionario VOX Griego Español, Diccionario Médico, Biológico, Histológico y Etimológico de la Universidad de Salamanca y Diccionario de Términos Médicos de la Real Academia Nacional de Medicina, así como algunos artículos y libros clásicos de anatomía. Los resultados indicaron que el término amígdala tiene el mismo significado en griego como en latín, en donde ἀμυγδαλέα, ἀμυγδαλέας (pr. amygdaléa, amygdaléas) es el árbol del almedro y ἀμυγδάλη, ἀμυγδάλης (pr. amygdále, amygdáles) significa almendra. Conociendo tanto la anatomía como la fisiología de esta estructura su forma no se asemeja a la de una almendra y su denominación actual no está acorde con los requerimientos de la FIPAT por lo cual consideramos que esta debe ser revisada.

SUMMARY: In medical terminology the term brain amygdala is used to refer to the structure that according to the Terminologia Neuroanatomica and Terminologia Anatomica is known as the amydaloid body, which is made up of various nuclei and is responsible for emotions, behavior, regulation of the anxiety, aggression, fear, emotional memory, social cognition, and responses to stress. Being the cerebral amygdala such an important structure, the objective of this study was: to analyze the meaning of the term cerebral amygdala in Terminologia Neuroanatomica and in Terminologia Anatomica and to contrast if the origin of its Greek Latin roots agrees with the function of this structure according to the requirements of the FIPAT. For this, the dictionaries of the Royal Spanish Academy, the DGE Greek Spanish Dictionary, the VOX Greek Spanish Dictionary, the Medical, Biological, Histological and Etymological Dictionary of the University of Salamanca, the Dictionary of the Royal National Academy of Medicine, as well as some articles and classic books of anatomy. The results indicated that the term amygdala has the same meaning in Greek as in Latin, where? ἀμυγδαλέα, ἀμυγδαλέας (pr. Amygdaléa, amygdaléas) is the almond tree andἀμυγδάλη, ἀμυγδάλης (pr. amygdále, amygdáles) means almond. Knowing both the anatomy and the physiology of this structure, its shape does not resemble that of an almond and its current name is not in accordance with the requirements of the FIPAT, for which we consider that it should be revised.

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.

Induction of Zenk protein expression within the nucleus taeniae of the amygdala of pigeons following tone and shock stimulation

In this study, we evaluated the expression of the Zenk protein within the nucleus taeniae of the pigeon’s amygdala (TnA) after training in a classical aversive conditioning, in order to improve our understanding of its functional role in birds. Thirty-two 18-month-old adult male pigeons (Columba livia), weighing on average 350 g, were trained under different conditions: with tone-shock associations (experimental group; EG); with shock-alone presentations (shock group; SG); with tone-alone presentations (tone group; TG); with exposure to the training chamber without stimulation (context group; CG), and with daily handling (naive group; NG). The number of immunoreactive nuclei was counted in the whole TnA region and is reported as density of Zenk-positive nuclei. This density of Zenk-positive cells in the TnA was significantly greater for the EG, SG and TG than for the CG and NG (P < 0.05). The data indicate an expression of Zenk in the TnA that was driven by experience, supporting the role of this brain area as a critical element for neural processing of aversive stimuli as well as meaningful novel stimuli.

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.

The importance of accurate anatomic assessment for the volumetric analysis of the amygdala

There is a wide range of values reported in volumetric studies of the amygdala. The use of single plane thick magnetic resonance imaging (MRI) may prevent the correct visualization of anatomic landmarks and yield imprecise results. To assess whether there is a difference between volumetric analysis of the amygdala performed with single plane MRI 3-mm slices and with multiplanar analysis of MRI 1-mm slices, we studied healthy subjects and patients with temporal lobe epilepsy. We performed manual delineation of the amygdala on T1-weighted inversion recovery, 3-mm coronal slices and manual delineation of the amygdala on three-dimensional volumetric T1-weighted images with 1-mm slice thickness. The data were compared using a dependent t-test. There was a significant difference between the volumes obtained by the coronal plane-based measurements and the volumes obtained by three-dimensional analysis (P < 0.001). An incorrect estimate of the amygdala volume may preclude a correct analysis of the biological effects of alterations in amygdala volume. Three-dimensional analysis is preferred because it is based on more extensive anatomical assessment and the results are similar to those obtained in post-mortem studies.

Increased sweet taste preference following the lesion of basolateral nucleus of amygdala (BLA) in rat.

A study of gustatory preference was carried out in Wistar strain albino rats by electrolytically lesioning the basolateral nucleus of amygdala. The intake of sweet tasting saccharin (Sn-0.1% soln w/v), NaCl solutions (1% Soln w/v) and tap water, were tested in single bottle, 2 bottle choice and 3 bottle choice situations. The consumption of fluids both before and after the stereotaxic surgery was recorded and statistically analysed. Lesion of BLA increased the intake of all fluids in the single bottle tests (P < 0.01). But the increase in the group provided with saccharin was more than that in other two groups. When taste preference was tested using 2-bottle and 3-bottle choice situations, the lesioned rats were seeking Sn solution. In our previous study, we found that the lesion of BLA increased fluid intake in rats. The intake, in the present study was more in those animals provided with Sn solution. When choice was given, the rats shifted their preference from water to the Sn following the lesion. Thus this study confirms that BLA is involved in the preference for sweet tasting solution over the NaCl or plain water.

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

Amygdalar involvement in pain.

The limbic system has been implicated in the modulation of pain. The aim of this study was to determine the role of amygdala in different types of pain, viz., phasic and tonic. Unilateral stimulation of central nucleus of amygdala (CeA), basolateral nucleus (BL) and medial amygdaloid (MeA) in conscious rats resulted in the reduction of the tonic formalin-induced pain. The thresholds for simple vocalization (SV) and vocalization after-discharge (VA) were elevated during amygdalar stimulation in the tail-flick (phasic pain) test. However, the threshold for tail-flick (TF) evoked by electric shock was not affected. Tail-flick latency (TFL) to noxious heat was accentuated during amygdalar stimulation. These results suggest that amygdala had a modulatory role in the descending endogenous pain control mechanisms.