Search results for "Move"
showing 10 items of 2153 documents
miR379-410 cluster miRNAs regulate neurogenesis and neuronal migration by fine-tuning N-cadherin
2014
N-cadherin-mediated adhesion is essential for maintaining the tissue architecture and stem cell niche in the developing neocortex. N-cadherin expression level is precisely and dynamically controlled throughout development; however, the underlying regulatory mechanisms remain largely unknown. MicroRNAs (miRNAs) play an important role in the regulation of protein expression and subcellular localisation. In this study, we show that three miRNAs belonging to the miR379–410 cluster regulate N-cadherin expression levels in neural stem cells and migrating neurons. The overexpression of these three miRNAs in radial glial cells repressed N-cadherin expression and increased neural stem cell different…
Can we understand human brain development from experimental studies in rodents?
2020
Animal models are needed to gain an understanding of the genetic, molecular, cellular, and network mechanisms of human brain development. In rodents, a large spectrum of in vitro and in vivo approaches allows detailed analyses and specific experimental manipulations for studying the sequence of developmental steps in corticogenesis. Neurogenesis, neuronal migration, cellular differentiation, programmed cell death, synaptogenesis, and myelination are surprisingly similar in the rodent cortex and the human cortex. Spontaneous EEG activity in the pre- and early postnatal human cortex resembles the activity patterns recorded with intracortical multi-electrode arrays in newborn rodents. This ear…
Regular theta-firing neurons in the nucleus incertus during sustained hippocampal activation
2015
This paper describes the existence of theta-coupled neuronal activity in the nucleus incertus (NI). Theta rhythm is relevant for cognitive processes such as spatial navigation and memory processing, and can be recorded in a number of structures related to the hippocampal activation including the NI. Strong evidence supports the role of this tegmental nucleus in neural circuits integrating behavioural activation with the hippocampal theta rhythm. Theta oscillations have been recorded in the local field potential of the NI, highly coupled to the hippocampal waves, although no rhythmical activity has been reported in neurons of this nucleus. The present work analyses the neuronal activity in t…
Neuronal populations mediating the effects of endocannabinoids on stress and emotionality
2011
An adequate emotional response to stress is essential for survival and requires the fine-tuned regulation of several distinct neuronal circuits. Therefore, a precise control of these circuits is necessary to prevent behavioral imbalances. During the last decade, numerous investigations have evidenced that the endocannabinoid (eCB) system is able to crucially control stress coping. Its central component, the cannabinoid type 1 receptor (CB1 receptor), is located at the presynapse, where it is able to attenuate neurotransmitter release after its activation by postsynaptically produced and released eCBs. To date, the eCB system has been found to control the neurotransmitter release from severa…
Analysis of a spatial orientation memory in Drosophila.
2008
Flexible goal-driven orientation requires that the position of a target be stored, especially in case the target moves out of sight. The capability to retain, recall and integrate such positional information into guiding behaviour has been summarized under the term spatial working memory. This kind of memory contains specific details of the presence that are not necessarily part of a long-term memory. Neurophysiological studies in primates indicate that sustained activity of neurons encodes the sensory information even though the object is no longer present. Furthermore they suggest that dopamine transmits the respective input to the prefrontal cortex, and simultaneous suppression by GABA s…
Three-dimensional Hall effect accelerometer for recording head movements of freely moving laboratory animals
1991
A Hall effect device was constructed for a measurement of head movements in three spatial dimensions during classical conditioning experiments in cats. A Hall sensor was used to detect movements of a magnetic fragment floating in a small (15 x 15 mm) cube. The magnetic fragment was kept in the centre of the sealed cube with a thin coil spring which was filled with thin oil for damping excessive afteroscillations. A comparison of this device to a commercial accelerometer showed that the accuracy of the Hall device is sufficient for the movement recordings and that the device is sensitive also to slowly accelerating movements. The construction is compact and can be easily mounted, for example…
Architecture and cell types of the adult subventricular zone: in search of the stem cells.
1998
Neural stem cells are maintained in the subventricular zone (SVZ) of the adult mammalian brain. Here, we review the cellular organization of this germinal layer and propose lineage relationships of the three main cell types found in this area. The majority of cells in the adult SVZ are migrating neuroblasts (type A cells) that continue to proliferate. These cells form an extensive network of tangentially oriented pathways throughout the lateral wall of the lateral ventricle. Type A cells move long distances through this network at high speeds by means of chain migration. Cells in the SVZ network enter the rostral migratory stream (RMS) and migrate anteriorly into the olfactory bulb, where t…
Neurogenesis in adult subventricular zone
2002
Much excitement has been generated by the identification of adult brain regions harboring neural stem cells and their continual generation of new neurons throughout life. This is an important departure from traditional views of the germinal potential of the postnatal brain. However, a more profound
Investigating the use of primary adult subventricular zone neural precursor cells for neuronal replacement therapies
2002
With the relatively recent discovery that neurogenesis persists throughout life in restricted regions of the adult mammalian brain, including those of human beings, there has been great interest in the use of adult-derived neural stem cells for neuronal replacement. There are many great hurdles that must be overcome in order for such replacement strategies to succeed. In this review, we outline some of these hurdles and discuss recent experiments that investigate the potential of using neural precursor cells found in the subventricular zone of the adult brain for brain repair.
Subplate Cells: Amplifiers of Neuronal Activity in the Developing Cerebral Cortex
2009
Due to their unique structural and functional properties, subplate cells are ideally suited to function as important amplifying units within the developing neocortical circuit. Subplate neurons have extensive dendritic and axonal ramifications and relatively mature functional properties, i.e. their action potential firing can exceed frequencies of 40 Hz. At earliest stages of corticogenesis subplate cells receive functional synaptic inputs from the thalamus and from other cortical and non-cortical sources. Glutamatergic and depolarizing GABAergic inputs arise from cortical neurons and neuromodulatory inputs arise from the basal forebrain and other sources. Activation of postsynaptic metabot…