Correlation Analysis of Molecularly-Defined Cortical Interneuron Populations with Morpho-Electric Properties in Layer V of Mouse Neocortex / 神经科学通报·英文版

Cortical interneurons can be categorized into distinct populations based on multiple modalities, including molecular signatures and morpho-electrical (M/E) properties. Recently, many transcriptomic signatures based on single-cell RNA-seq have been identified in cortical interneurons. However, whether different interneuron populations defined by transcriptomic signature expressions correspond to distinct M/E subtypes is still unknown. Here, we applied the Patch-PCR approach to simultaneously obtain the M/E properties and messenger RNA (mRNA) expression of >600 interneurons in layer V of the mouse somatosensory cortex (S1). Subsequently, we identified 11 M/E subtypes, 9 neurochemical cell populations (NCs), and 20 transcriptomic cell populations (TCs) in this cortical lamina. Further analysis revealed that cells in many NCs and TCs comprised several M/E types and were difficult to clearly distinguish morpho-electrically. A similar analysis of layer V interneurons of mouse primary visual cortex (V1) and motor cortex (M1) gave results largely comparable to S1. Comparison between S1, V1, and M1 suggested that, compared to V1, S1 interneurons were morpho-electrically more similar to M1. Our study reveals the presence of substantial M/E variations in cortical interneuron populations defined by molecular expression.

Cerebral localization of higher functions: anatomic structures before the identification of their memory function / Localização cerebral de funções superiores: estruturas anatômicas antes da identificação de suas funções de memória

The nature of memory and the search for its localization have been a subject of interest since Antiquity. After millennia of hypothetical concepts the core memory-related structures finally began to be identified through modern scientifically-based methods at the diencephalic, hippocampal, and neocortical levels. However, there was a clear temporal delay between the finding of these anatomic structures ignoring their function, and their identification related to memory function. Thus, the core structures begun to be identified with a pure anatomical view in the late Middle Ages on, while the memory function related to them was discovered much later, in the late Modern Period.

A natureza da memória e a busca de sua localização tem sido objeto de interesse desde a Antiguidade. Após milênios de conceitos hipotéticos as estruturas centrais relacionadas com a memória finalmente começaram a ser identificadas através de métodos modernos com base científica, nos níveis diencefálico, hipocampal e neocortical. Entretanto, houve um claro retardo temporal entre o achado dessas estruturas anatômicas ignorando sua função e sua identificação relacionada à função da memória. Assim, as estruturas centrais começaram a ser identificadas com uma visão puramente anatômica da Idade Média tardia em diante, enquanto a função da memória relacionada com as mesmas foi descoberta muito mais tarde, no Período Moderno tardio.

Cerebral localization of higher functions: Memory-related anatomic structures / Localização cerebral de funções superiores: estruturas anatômicas relacionadas com a memória. achados iniciais

ABSTRACT The nature of memory and the search for its localization have been a subject of interest since Antiquity. After millennia of theoretical concepts, shifting from the heart to the brain, then from the ventricles to solid parts, the core memory-related structures finally began to be identified through modern scientifically-based methods at the diencephalic and cortical (hippocampal and neocortical) levels, mostly in the late Modern period, culminating in the current state of knowledge on the subject.

RESUMO A natureza da memória e a busca de sua localização tem sido objeto de interesse desde a Antiguidade. Após milênios de conceitos teóricos, mudando do coração para o cérebro e daí dos ventrículos para as partes sólidas, as estruturas centrais relacionadas com a memória finalmente começaram a ser identificadas através de métodos modernos com base científica, nos níveis diencefálico e cortical (hipocampal e neocortical), principalmente no período Moderno tardio, aproximando-se do estado atual do conhecimento sobre o tema.

Farnesylation-defective Rheb Increases Axonal Length Independently of mTORC1 Activity in Embryonic Primary Neurons

Rheb (Ras homolog enriched in the brain) is a small GTPase protein that plays an important role in cell signaling for development of the neocortex through modulation of mTORC1 (mammalian-target-of-rapamycin-complex-1) activity. mTORC1 is known to control various biological processes including axonal growth in forming complexes at the lysosomal membrane compartment. As such, anchoring of Rheb on the lysosomal membrane via the farnesylation of Rheb at its cysteine residue (C180) is required for its promotion of mTOR activity. To test the significance of Rheb farnesylation, we overexpressed a farnesylation mutant form of Rheb, Rheb C180S, in primary rat hippocampal neurons and also in mouse embryonic neurons using in utero electroporation. Interestingly, we found that Rheb C180S maintained promotional effect of axonal elongation similar to the wild-type Rheb in both test systems. On the other hand, Rheb C180S failed to exhibit the multiple axon-promoting effect which is found in wild-type Rheb. The levels of phospho-4EBP1, a downstream target of mTORC1, were surprisingly increased in Rheb C180S transfected neurons, despite the levels of phosphorylated mTOR being significantly decreased compared to control vector transfectants. A specific mTORC1 inhibitor, rapamycin, also could not completely abolish axon elongation characteristics of Rheb C180S in transfected cells. Our data suggests that Rheb in a non-membrane compartment can promote the axonal elongation via phosphorylation of 4EBP1 and through an mTORC1-independent pathway.

Immunoreactivity of PCNA in the Cerebellum of Developing Guinea Pig

The investigation of the embryonic development of the cerebellum has a long history. The postnatal normal development of the cerebellum in rodents and other animals became a popular topic for morphological investigations nearly a century ago. However, surprisingly, only a few studies are available regarding the prenatal normal development of the rodent cerebellum, especially in guinea pigs. Cell proliferation is essential for the development of the nervous system. The assessment of cell proliferation can be achieved by using various methods. In this study, we investigated the cell proliferation of the cerebellar cortex in guinea pigs at different stages of pregnancy and in postnatal life. Fetuses were obtained by cesarean section at 50 or 60 days of gestation (dg). Immunohistochemistry was performed with proliferating cell nuclear antigen (PCNA) antibody in the cerebellum. Strong PCNA immunoreactivity was observed in the external granular layer (EGL), which is a neurogenic zone in the cerebellum. The proportion of PCNA-IR cells was greater at 1 week than at 60 dg in lobule I, but not lobule VIII. After 50 dg, the width of the EGL continued to decline until 1 week, due to the maturation of the EGL cells. These results demonstrate the pattern of PCNA immunoreactivity in the developing cerebellum of guinea pigs. This serves as a guideline to study abnormal cerebellum development.

Recapitulating cortical development with organoid culture in vitro and modeling abnormal spindle-like (ASPM related primary) microcephaly disease

The development of a cerebral organoid culture in vitro offers an opportunity to generate human brain-like organs to investigate mechanisms of human disease that are specific to the neurogenesis of radial glial (RG) and outer radial glial (oRG) cells in the ventricular zone (VZ) and subventricular zone (SVZ) of the developing neocortex. Modeling neuronal progenitors and the organization that produces mature subcortical neuron subtypes during early stages of development is essential for studying human brain developmental diseases. Several previous efforts have shown to grow neural organoid in culture dishes successfully, however we demonstrate a new paradigm that recapitulates neocortical development process with VZ, OSVZ formation and the lamination organization of cortical layer structure. In addition, using patient-specific induced pluripotent stem cells (iPSCs) with dysfunction of the Aspm gene from a primary microcephaly patient, we demonstrate neurogenesis defects result in defective neuronal activity in patient organoids, suggesting a new strategy to study human developmental diseases in central nerve system.

Unified principles of thalamo-cortical processing: the neural switch

It has been reported that cross-frequency interactions may play an important role in local processing within thalamus and neocortex, as well as information transfer between subcortical and cortico-cortical brain regions. Strong commonalities in rhythmic network properties have been observed across recording techniques and task demands, but strong neuroscientific theories to situate such observations within a unified framework with direct relevance to explain neuropathologies remain scarce. Based on a comprehensive review of animal and human literature, we probe and introduce a neurophysiological framework to explain how coordinated cross-frequency and interregional oscillatory cortical dynamics underlie typical and atypical brain activation, and the formation of distributed functional ensembles supporting cortical networks underpinning perception and cognition. We propose that local regional activation by an external stimulus via a sensory pathway entails (1) attenuated alpha (8–14 Hz) and increased theta (4–8 Hz) and gamma (30–50 Hz) oscillatory activity, and (2) increased interactions among theta and gamma rhythms. These local dynamics also mediate the integration of activated neural populations into largescale functional assemblies through neuronal synchronization. This comprehensive perspective into the animal and human literature indicates a further thinking beyond synchrony and connectivity and the readiness for more hypothesis-driven research and modeling toward unified principles of thalamo-cortical processing. We further introduced such a possible framework: “The ATG switch”. We also discussed evidence that alpha-theta-gamma dynamics emerging from thalamocortical interactions may be implicated and disrupted in numerous neurological and neuropsychiatric conditions.

Dementia due to Meningovascular Syphilis in Medial Temporal Lobe and Cognitive Rehabilitation

The temporal lobe is essential in saving declarative memory and plays an important role along with the cerebral neocortex in creating and maintaining long-term memory. Damage to the temporal lobe is expected to result in cognitive impairment or dementia, which has characteristic symptoms such as cognitive and behavioral dysfunction and decreasing self-reliance in activities of daily living. We report on a patient, who suffered from dementia due to meningovascular syphilis affecting the medial temporal lobe, and on the outcome of cognitive rehabilitation.

Dementia due to Meningovascular Syphilis in Medial Temporal Lobe and Cognitive Rehabilitation

The temporal lobe is essential in saving declarative memory and plays an important role along with the cerebral neocortex in creating and maintaining long-term memory. Damage to the temporal lobe is expected to result in cognitive impairment or dementia, which has characteristic symptoms such as cognitive and behavioral dysfunction and decreasing self-reliance in activities of daily living. We report on a patient, who suffered from dementia due to meningovascular syphilis affecting the medial temporal lobe, and on the outcome of cognitive rehabilitation.

Clinical Utility of Interictal High-Frequency Oscillations Recorded with Subdural Macroelectrodes in Partial Epilepsy

BACKGROUND AND PURPOSE: There is growing interest in high-frequency oscillations (HFO) as electrophysiological biomarkers of the epileptic brain. We evaluated the clinical utility of interictal HFO events, especially their occurrence rates, by comparing the spatial distribution with a clinically determined epileptogenic zone by using subdural macroelectrodes. METHODS: We obtained intracranial electroencephalogram data with a high temporal resolution (2000 Hz sampling rate, 0.05-500 Hz band-pass filter) from seven patients with medically refractory epilepsy. Three epochs of 5-minute, artifact-free data were selected randomly from the interictal period. HFO candidates were first detected by an automated algorithm and subsequently screened to discard false detections. Validated events were further categorized as fast ripple (FR) and ripple (R) according to their spectral profiles. The occurrence rate of HFOs was calculated for each electrode contact. An HFO events distribution map (EDM) was constructed for each patient to allow visualization of the spatial distribution of their HFO events. RESULTS: The subdural macroelectrodes were capable of detecting both R and FR events from the epileptic neocortex. The occurrence rate of HFO events, both FR and R, was significantly higher in the seizure onset zone (SOZ) than in other brain regions. Patient-specific HFO EDMs can facilitate the identification of the location of HFO-generating tissue, and comparison with findings from ictal recordings can provide additional useful information regarding the epileptogenic zone. CONCLUSIONS: The distribution of interictal HFOs was reasonably consistent with the SOZ. The detection of HFO events and construction of spatial distribution maps appears to be useful for the presurgical mapping of the epileptogenic zone.

Neuronal signaling in central nervous system / 生理学报

A new method of axon recording through axon bleb has boosted the studies on the functional role of central nervous system (CNS) axons. Using this method, we have revealed the mechanisms underlying the initiation and propagation of the digital-mode signal, all-or-none action potentials (APs), in neocortical pyramidal neurons. Accumulation of the low-threshold Na(+) channel subtype Na(v)1.6 at the distal end of the axon initial segment (AIS) determines the lowest threshold for AP initiation, whereas accumulation of the high-threshold subtype Na(v)1.2 at the proximal region of the AIS promotes AP backpropagation to the soma and dendrites. Through dual recording from the soma and the axon, we have showed that subthreshold membrane potential (V(m)) fluctuations in the soma propagate along the axon to a long distance and probably reach the axon terminals. Paired recording from cortical neurons has revealed that these V(m) changes in the soma modulate AP-triggered synaptic transmission. This new V(m)-dependent mode of synaptic transmission is called analog communication. Unique properties of axonal K(+) channels (K(v)1 channels) may contribute to shaping the AP waveform, particularly its duration, and thus controlling synaptic strength at different levels of presynaptic V(m). The level of background Ca(2+) may also participate in mediating the analog signaling. Together, these findings enrich our knowledge on the principles of neuronal signaling in the CNS and help understand how the brain works.

Diagnostic methods for extra-temporal neocortical focal epilepsies: present and future / Métodos diagnósticos das epilepsias focais neocorticais extratemporais: presente e futuro

The progress of epilepsies diagnosis has been great, but, amongst the diagnostic detailing that demand research, one of the most important is the essential lateralization and localization of epileptogenic zone, considered as the cerebral cortex region, that removed, will result in a free state of seizures. The present study aims to analyze the possible uses of proton spectroscopy for clinical and pre-surgical evaluation of focal extratemporal epilepsies, since this group presents the highest difficulty degree for lateralizing and locating epileptogenic zones. In almost all cases, a non invasive diagnosis can be performed using routine electroencephalography, video-electroencephalography - considered as gold standard, and magnetic resonance imaging. However, when the results of these exams are contradictory, some patients need invasive techniques, as the intra-cranial video-EEG, using deep electrodes, sub-dural strip and grid, that are associated with increased diagnostic cost and risk of complications, as cerebral hemorrhages and intra-cranial infections. Proton spectroscopy appears as a possibility, given its capacity to evaluate cerebral metabolism, by N-acetyl-aspartate (NAA), creatine (Cre) and choline (Cho) concentrations, amongst other metabolites. This non invasive method may provide time reduction of this evaluation and reliable level improvement for this topographical diagnosis.

Tem sido grande o progresso no diagnóstico das epilepsias, mas dentre os detalhamentos diagnósticos a exigir pesquisas, estão a lateralização e a localização precisas da zona epileptogênica, considerada como a região do córtex cerebral que, removida, irá resultar num estado livre de crises. Por meio de revisão da literatura, o objetivo deste estudo é expor e analisar os métodos diagnósticos das epilepsias neocorticais extratemporais, dadas as características que as tornam mais complexas do que as epilepsias temporais visto que estas apresentam o maior grau de dificuldade para lateralização e localização das zonas epileptogênicas. Na maior parte dos casos, o diagnóstico pode ser firmado de forma não invasiva, empregando-se a eletrencefalografia de superfície, a vídeo-eletrencefalografia, considerada o padrão-ouro, e a imagem por ressonância magnética. No entanto, quando os resultados dessas investigações são contraditórios, alguns pacientes necessitam de técnicas invasivas, como o vídeo-EEG intracraniano, utilizando eletrodos profundos, placas ou estrias subdurais, que se associam ao aumento do custo diagnóstico e do risco de complicações, como as hemorragias cerebrais e as infecções intracranianas. A espectroscopia de prótons surge como uma possibilidade, dada sua capacidade de avaliar o metabolismo cerebral, por meio das alterações de N-acetil aspartato (NAA), creatina (Cr) e colina (Co), dentre outros metabólitos. Esse método não invasivo pode reduzir o tempo de avaliação e melhorar o nível de confiança desse diagnóstico topográfico.

Identification of 1,531 cSNPs from Full-length Enriched cDNA Libraries of the Korean Native Pig Using in Silico Analysis

Sequences from the clones of full-length enriched cDNA libraries serve as valuable resources for functional genomics related studies, genome annotation and SNP discovery. We analyzed 7,392 high-quality chromatograms (Phred value >30) obtained from sequencing the 5' ends of clones derived from full-length enriched cDNA libraries of Korean native pigs including brainstem, liver, cerebellum, neocortex and spleen libraries. In addition, 50,000 EST sequence trace files obtained from GenBank were combined with our sequences to identify cSNPs in silico. The process generated 11,324 contigs, of which 2,895 contigs contained at least one SNP and among them 610 contigs had a minimum of one sequence from Korean native pigs. Of 610 contigs, we randomly selected 262 contigs and performed in silico analysis for the identification of cSNPs. From the results, we identified 1,531 putative coding single nucleotide polymorphisms (cSNPs) and the SNP detection frequency was one SNP per 465 bp. A large-scale sequencing result of clones from full-length enriched cDNA libraries and identified cSNPs will serve as a useful resource to functional genomics related projects such as a pig HapMap project in the near future

Topographical Propagation of alpha-synuclein Pathology in Parkinson's Disease: Phenomenology and Hypothetical Mechanism

Parkinson's disease is an age-related, slowly progressing neurodegenerative disorder characterized by abnormal deposition of aggregated alpha-synuclein in neuronal cell bodies (Lewy bodies) and neurites (Lewy neurites), as well as in glia. Based on semiquantitative assessment of Lewy pathologies in autopsy samples, a staging system was proposed indicating a highly predictable sequence of pathological progression. This staging system implicates a propagation of alpha-synuclein aggregation throughout the brain with an ascending pattern from lower brain stem to neocortex. The underlying mechanism for the pathological propagation is unknown. However, the recent discoveries on the secretion of neuronal alpha-synuclein and subsequent uptake of the protein by neighboring cells propose an interneuronal transmission of alpha-synuclein aggregates as a novel mechanism for the spread of Lewy pathology in PD. Elucidation of this mechanism is likely to identify novel therapeutic strategies that halt the progression of PD.

Determinación del perfil de dominancia cerebral o formas de pensamiento de los estudiantes de primer semestre del programa de bacteriología y laboratorio clínico de la Universidad Colegio Mayor de Cundinamarca / Determination of the profile of cerebral dominancy or forms of thought of the students of first semester of the bacteriology Program and Clinical Laboratory College Mayor of Cundinamarca

El objetivo de esta investigación, basados en el modelo de Ned Hermann y los estudios realizados por Omar Gardie, fue determinar el perfil de dominancia cerebral o formas de pensamiento de los estudiantes de primer semestre del programa de Bacteriología y Laboratorio Clínico de la Universidad Colegio Mayor de Cundinamarca. El 50/100 de los estudiantes presentan dominancia en el cuadrante cortical izquierdo, el 43/100 en el cuadrante límbico derecho y el 13,3/100 en el cortical derecho. 46.6 de los estudiantes poseen dominancia simple y el 50/100 dominancia doble. Los resultados obtenidos permitirán a los docentes conocer las potencialidades cognitivas y las formas de pensamiento de sus estudiantes con el fin de direccionar la búsqueda y la construcción de conocimiento en el proceso de enseñanza-aprendizaje de los mismos. El 50/100 de los estudiantes presentan dominancia en el cuadrante cortical izquierdo, el 43/100 en el cuadrante límbico derecho y el 13,3/100 en el cortical derecho. El 46,6/100 de los estudiantes poseen dominancia simple y el 50/100 dominancia doble.

Brain Mapping for Memory and Learning / 대한정신약물학회지

Functional magnetic resonance imaging and positron emission tomography studies have identified brain regions associated with different forms of memory and learning. The purpose of this study was to summarize the results of functional neuroimaging studies to construct brain maps for memory and learning. Working memory is associated with the bilateral prefrontal, anterior cingulate, and temporal, and parietal regions ; semantic memory with the left prefrontal and temporal regions ; episodic memory encoding with the left prefrontal and medial temporal regions ; episodic memory retrieval with the right prefrontal, and posterior midline, and medial temporal regions ; skill learning with the motor, parietal, and subcortical regions ; priming with the fusiform and neocortex ; and classical conditioning with the cerebellum. More recent studies have provided higher specificity, by dissociating the neural correlates of different subcomponents of complex memory tasks and the cognitive roles of different subregions of larger brain areas.

Considerações sobre a evolução filogenética do sistema nervoso, o comportamento e a emergência da consciência / Considerations about the nervous system phylogenetic evolution, behavior, and the emergence of consciousness

Tendo como base dados de literatura, esta revisão trata dos aspectos genéricos da evolução filogenética do sistema nervoso central, ressaltando em particular o desenvolvimento evolutivo das estruturas encefálicas relacionadas com o comportamento e com as funções cognitivas que vieram caracterizar o ser humano. Sobre as estruturas límbicas, que por ocasião do advento dos mamíferos evolutivamente se desenvolveram sobre o topo do sistema nervoso mais primitivo dos seus ancestrais, o ulterior desenvolvimento cortical com neurônios dispostos em camadas constituiu a base estrutural que viabilizou a discriminação fina das funções sensitivas e sensoriais, a maior complexidade das funções motoras e o desenvolvimento das funções cognitivas e intelectuais que acabaram caracterizando o ser humano. O conhecimento da evolução filogenética do sistema nervoso central nos permite inferir possíveis correlações entre as estruturas encefálicas que se desenvolveram ao longo do processo evolutivo e o comportamento dos seus respectivos seres. Nesta direção, sem se deter em questões de ordem conceitual, a presente revisão termina discutindo possíveis paralelos entre a evolução do sistema nervoso central e a emergência da consciência, à luz das recentes contribuições sobre o assunto.

This text reviews the generic aspects of the central nervous system evolutionary development, emphasizing the developmental features of the brain structures related with behavior and with the cognitive functions that finally characterized the human being. Over the limbic structures that with the advent of mammals were developed on the top of the primitive nervous system of their ancestrals, the ultimate cortical development with neurons arranged in layers constituted the structural base for an enhanced sensory discrimination, for more complex motor activities, and for the development of cognitive and intellectual functions that finally characterized the human being. The knowledge of the central nervous system phylogeny allow us particularly to infer possible correlations between the brain structures that were developed along phylogeny and the behavior of their related beings. In this direction, without discussing its conceptual aspects, this review ends with a discussion about the central nervous system evolutionary development and the emergence of consciousness, in the light of its most recent contributions.

Effects of Quetiapine on the Immobilization Stress-induced BDNF and CRF Expression in Rat Brain / 대한정신약물학회지

OBJECTIVE: In this study we examined the effects of quetiapine on the immobilization stress-induced brain-derived neurotrophic factor (BDNF) and corticotropin-releasing factor (CRF) expression in rat brain. We also assessed the antidepressant activity of quetiapine. METHOD: We used in situ hybridization to examine the effects of chronic administration of quetiapine in gene transcription. This study also examined the influence of quetiapine in an animal model of depression, the forced swimming test (FST). RESULTS: 1) Repeated immobilization stress (2 hr daily for 3 weeks) decreased mRNA levels of BDNF in the hippocampus (p<0.01), parietal cortex (p<0.01) and pyriform cortex (p<0.05). 2) Repeated immobilization stress increased mRNA levels of CRF in the hypothalamic paraventricular nucleus (PVN)(p<0.01). 3) Chronic quetiapine (10 mg/kg) treatment (daily for 3 weeks) alone significantly increased BDNF mRNA expression in the dentate gyrus of hippocampus when compared to controls under basal conditions (p<0.01), whereas no such effect was observed in the neocortex. 4) Chronic pretreatment of quetiapine also markedly increased the stress-induced decrease of BDNF mRNA expression in the hippocampus (p<0.01) and neocortex (p<0.01). 5) Moreover, the stress-induced elevation of CRF mRNA expression was blocked by chronic quetiapine pretreatment in PVN (p<0.01) although chronic quetiapine treatment alone did not significantly reduce CRF mRNA levels in comparison to controls under basal condition. 6) When rats received acutely quetiapine, quetiapine did reduce the immobility time at 10 mg/kg, as compared with the control group (p<0.05). CONCLUSION : These results suggest that quetiapine has not only potentially an antidepressant effect but also a neuroprotective action in schizophrenia and this effect may be related to its antipsychotic effect in patients with schizophrenia.

Pathogenic Mechanism of Alzheimer's Disease / 한양의대학술지

Alzheimer's disease (AD) is regarded as a prototype of the neurodegenerative disorder characterized by progressive memory impairment and multiple cognitive deficits in mid- to late- life. Its pathological hallmarks consist of neuritic plaques and neurofibrillary tangles in the cerebral cortex, accompanied by neuronal loss. These neuropathological findings are prominent in the temporal neocortex and hippocampus. There are a small proportion of AD cases (10%) that appear to be transmitted as pure autosomal dominant Mendelian traits with age-dependent, but, high penetrance. Molecular genetic studies on pedigrees with the latter type of familial Alzheimer's disease (FAD) with molecular genetic tools has led to the discovery of four different genetic loci associated with inherited susceptibility to AD. It is generally suggested that late-onset AD is caused by a complex set of genetic and environmental factors, such as diet, blood pressure, education, social interaction, and others. In this communication, some of the known risk factors relevant to etiopathogenesis of AD to date will be briefly reviewed.

Efeitos do etanol sobre a migração neuronal na formação do neocórtex cerebral / Effects of ethanol on the neuronal migration in the brain neocortex formation

Os neurônios migram das zonas ventriculares e subventriculares, através das glias radial e tangencial, para formar as várias camadas corticais do neocórtex adulto. A exposição crônica de ratas grávidas ao etanol desencadeia ectopia, heterotopia e despopulação neuronial, promovendo a chamada síndrome alcóolica fetal. O tratamento agudo de ratas grávidas na data de nascimento dos neurônios também promove efeitos graves na formação do neocórtex.

The neurons migrate from the ventricular and subventricular zones, through the radial and tangential glia, to form the several cortical shells of the adult neocortex. The chronic exposure to ethanol of pregnant female rats causes ectopia, heterotopia and neuronal depopulation, producint the fetal alcoholic syndrome. The acute exposure of pregnant female rats at the neurons birth time also promotes severe effects on the neocortex formation.