TY - JOUR. T1 - Stress, glucocorticoid hormones, and hippocampal neural progenitor cells. T2 - Implications to mood disorders. AU - Kino, Tomoshige. PY - 2015. Y1 - 2015. N2 - The hypothalamic-pituitary-adrenal (HPA) axis and its end-effectors glucocorticoid hormones play central roles in the adaptive response to numerous stressors that can be either internal or external. Thus, this system has a strong impact on the brain hippocampus and its major functions, such as cognition, memory as well as behavior, and mood. The hippocampal area of the adult brain contains neural stem cells or more committed neural progenitor cells, which retain throughout the human life the ability of self-renewal and to differentiate into multiple neural cell lineages, such as neurons, astrocytes, and oligodendrocytes. Importantly, these characteristic cells contribute significantly to the above-indicated functions of the hippocampus, while various stressors and glucocorticoids influence proliferation, differentiation, ...
The hippocampus proper refers to the actual structure of the hippocampus which is made up of four regions or subfields. The subfields CA1, CA2, CA3, and CA4 use the initials of Cornu Ammonis , an earlier name of the hippocampus. Structure There are four regions in the hippocampus proper which form a neural circuit. CA1 is the first region in the hippocampal circuit, from which a major output pathway goes to layer V of the entorhinal cortex . Another significant output is to the subiculum . CA2 is a small region located between CA1 and CA3. It receives some input from layer II of the entorhinal cortex via the perforant path . Its pyramidal cells are more like those in CA3 than those in CA1. It is often ignored due to its small size. CA3 receives input from the mossy fibers of the granule cells in the dentate gyrus , and also from cells in the entorhinal cortex via the perforant path. The mossy fiber pathway ends in the stratum lucidum . The perforant path passes through the stratum lacunosum and ends in
TY - JOUR. T1 - Neural representation of spatial topology in the rodent hippocampus. AU - Chen, Zhe. AU - Gomperts, Stephen N.. AU - Yamamoto, Jun. AU - Wilson, Matthew A.. PY - 2014. Y1 - 2014. N2 - Pyramidal cells in the rodent hippocampus often exhibit clear spatial tuning in navigation. Although it has been long suggested that pyramidal cell activity may underlie a topological code rather than a topographic code, it remains unclear whether an abstract spatial topology can be encoded in the ensemble spiking activity of hippocampal place cells. Using a statistical approach developed previously, we investigate this question and related issues in greater detail.We recorded ensembles of hippocampal neurons as rodents freely foraged in one- and two-dimensional spatial environments and used a decode-to-uncover strategy to examine the temporally structured patterns embedded in the ensemble spiking activity in the absence of observed spatial correlates during periods of rodent navigation or awake ...
Figure 1. The structure of hippocampus.. Hippocampus Structure. The hippocampus is part of the limbic system known as the hippocampal region. Hippocampus can be divided into: dentate gyrus, hippocampus, subiculum, presubiculum, parasubiculum, and entorhinal cortex. The cell layer of the dentate gyrus, hippocampus, and lower tray is a single layer, collectively referred to as a hippocampal formation. A low cell density layer and a cell free layer are sandwiched between the upper and lower sides. The other parts have a structure of plurality of layers.. Hippocampus function. The function of the hippocampus is to control the recent memory of human beings. It is a bit like the memory of a computer. It will keep the memory in a few weeks or months, so that the body can quickly access the memory. The memory in the hippocampus is actually the connection between nerve cells. However, storing or throwing away certain information is not a conscious judgment, but is handled by the hippocampus in the human ...
TY - JOUR. T1 - Peripheral origin of IL-1Β production in the rodent hippocampus under in vivo systemic bacterial lipopolysaccharide (LPS) challenge and its regulation by P2X7 receptors. AU - Csölle, C.. AU - Sperlágh, B.. PY - 2010/2/1. Y1 - 2010/2/1. N2 - In this study we showed that in vivo bacterial lipopolysaccharide (LPS) challenge elevated IL-1Β level in the rodent hippocampus. Antagonists of P2X receptors inhibited LPS-induced IL-1Β level with a pharmacological profile similar to that of P2X7R and their inhibitory effect was attenuated in the absence of P2X7R. In wild-type mice, LPS overexpressed mRNA encoding P2X4 and P2X7 receptors in the hippocampus and caused also a remarkable increase in the levels of IL-1Β in the serum. The hippocampal increase of IL-1Β has substantially alleviated when contamination of circulating blood cells was excluded by transcardial perfusion, indicating the peripheral origin of hippocampal IL-1Β elevation. These results point to the key role of the ...
TY - JOUR. T1 - Intrahippocampal infusions of K-ATP channel modulators influence spontaneous alternation performance. T2 - Relationships to acetylcholine release in the hippocampus. AU - Stefani, Mark R.. AU - Gold, Paul E.. PY - 2001/1/15. Y1 - 2001/1/15. N2 - One mechanism by which administration of glucose enhances cognitive functions may be by modulating central ATP-sensitive potassium (K-ATP) channels. K-ATP channels appear to couple glucose metabolism and neuronal excitability, with channel blockade increasing the likelihood of neurosecretion. The present experiment examined the effects of glucose and the direct K-ATP channel modulators glibenclamide and lemakalim on spontaneous alternation performance and hippocampal ACh release. Rats received either artificial CSF vehicle or vehicle plus drug for two consecutive 12 min periods via microdialysis probes (3 mm; flow rate of 2.1 μl/min) implanted in the left hippocampus. During the second 12 min period, rats were tested for spontaneous ...
TY - JOUR. T1 - Androgens selectively modulate c-fos messenger RNA induction in the rat hippocampus following novelty. AU - Kerr, J. E.. AU - Beck, S. G.. AU - Handa, R. J.. N1 - Funding Information: The authors thank Dr Alan Nagahara and George Henja for help in the preparation of this manuscript. This material is based on work supported by an Advanced Predoctoral Fellowship from the Pharmaceutical Research and Manufacturers of America Foundation (JEK), National Science Foundation grants BNS 9109226, IBN 94-08890 and USPHS grants AA08696 (RJH) and K02-MH00880 (SGB). PY - 1996/8/2. Y1 - 1996/8/2. N2 - We have previously shown that androgen receptors are found in high concentrations in hippocampal CA1 pyramidal cells. To begin to explore the possible roles for androgen receptors in this area of the brain, we studied the effects of endogenous and exogenous androgen on tile behaviourally induced expression of cellular immediate early gene messenger RNAs. Adult male Fischer 344 rats were either ...
The hypothalamic-pituitary-adrenal (HPA) axis and its end-effectors glucocorticoid hormones play central roles in the adaptive response to numerous stressors that can be either internal or external. Thus, this system has a strong impact on the brain hippocampus and its major functions, such as cognition, memory as well as behavior, and mood. The hippocampal area of the adult brain contains neural stem cells or more committed neural progenitor cells, which retain throughout the human life the ability of self-renewal and to differentiate into multiple neural cell lineages, such as neurons, astrocytes, and oligodendrocytes. Importantly, these characteristic cells contribute significantly to the above-indicated functions of the hippocampus, while various stressors and glucocorticoids influence proliferation, differentiation, and fate of these cells. This review offers an overview of the current understanding on the interactions between the HPA axis/glucocorticoid stress-responsive system and hippocampal
TY - JOUR. T1 - Age dependence of homosynaptic non-NMDA mediated long-term depression in field CA1 of rat hippocampal slices. AU - Velíšek, Libor. AU - Moshé, Solomon L.. AU - Stanton, Patric K.. PY - 1993/10/15. Y1 - 1993/10/15. N2 - It has been hypothesized that high levels of presynaptic activity that fail to activate postsynaptic N-methyl-d-aspartate (NMDA) receptors may lead to long-term depression (LTD). Therefore, we tested the ability of high-frequency (50 Hz) synaptic stimulation in the presence of a blocker of NMDA receptors to elicit homosynaptic LTD at Schaffer collateral-CA1 synapses in hippocampal slices from 15-, 30- and 60-day-old rats. In control slices, there were no developmental differences in the incidence of long-term potentiation (LTP) of either EPSP slope or population spike amplitude. However, while NMDA receptor blockade with the specific antagonist d-2-amino-5-phosphonopentanoic acid (AP5; 25 μM) completely eliminated LTP in 30 and 60-day-olds, a significant number ...
Starting at the dentate gyrus and working inward along the S-curve of the hippocampus means traversing a series of narrow zones. The first of these, the dentate gyrus (DG), is actually a separate structure, a tightly packed layer of small granule cells wrapped around the end of the hippocampus proper, forming a pointed wedge in some cross-sections, a semicircle in others. Next come a series of Cornu Ammonis areas: first CA4 (which underlies the dentate gyrus), then CA3, then a very small zone called CA2, then CA1. The CA areas are all filled with densely packed Pyramidal cells similar to those found in the neocortex. After CA1 comes an area called the subiculum. After this comes a pair of ill-defined areas called the presubiculum and parasubiculum, then a transition to the cortex proper (mostly the entorhinal area of the cortex). Most anatomists use the term hippocampus proper to refer to the four CA fields, and hippocampal formation to refer to the hippocampus proper plus dentate gyrus and ...
The CA (Cornu Ammonis) fields, too, contain 3 distinct strata and house excitatory neurons known as pyramidal cells. The alveus is the most superficial layer and contains the commissural fibers of pyramidal cells via the fimbria, a major source of output from the hippocampus. Stratum oriens layer contains basal dendrites of the pyramidal cells and a large body of basket cells (inhibitory interneurons). This strata includes fibers from the septal and commissural areas that are received from the contralateral hippocampus. This region also contains the basal dendrites of the pyramidal cells. The next layer is the stratum pyramidale, named so because it contains the soma, or cell body, of the pyramidal cell. This layer in CA3 contains the mossy fiber connections and also houses interneurons. The stratum moleculare is divided into sublayers. The stratum lucidum is the thinnest layer and, in CA3, this area receives input from the dentate gyrus mossy fibers. Stratum radiatum contains apical dendrites ...
Newer approaches to characterizing hippocampal morphology can provide novel insights regarding cognitive function across the lifespan. We comprehensively assessed the relationships among age, hippocampal morphology, and hippocampal-dependent cognitive function in 137 healthy individuals across the a …
The ventral subiculum (vSUB) plays a key role in addiction, and identifying the neuronal circuits and synaptic mechanisms by which vSUB alters the excitability of dopamine neurons is a necessary step to understand the motor changes induced by cocaine. Here, we report that high-frequency stimulation of the vSUB (HFSvSUB) over-activates ventral tegmental area (VTA) dopamine neurons in vivo and triggers long-lasting modifications of synaptic transmission measured ex vivo. This potentiation is caused by NMDA-dependent plastic changes occurring in the bed nucleus of the stria terminalis (BNST). Finally, we report that the modification of the BNST-VTA neural circuits induced by HFSvSUB potentiates locomotor activity induced by a sub-threshold dose of cocaine. Our findings unravel a neuronal circuit encoding behavioral effects of cocaine in rats and highlight the importance of adaptive modifications in the BNST, a structure that influences motivated behavior as well as maladaptive behaviors associated ...
TY - JOUR. T1 - Synaptic plasticity in the hippocampus. T2 - Effects of estrogen from the gonads or hippocampus?. AU - Rune, G. M.. AU - Lohse, C.. AU - Prange-Kiel, J.. AU - Fester, L.. AU - Frotscher, M.. PY - 2006/2/1. Y1 - 2006/2/1. N2 - Different effects of estrogen on synaptic plasticity has been reported. Here, we summarise effects of low, gonad-derived serum estrogen concentrations, of intermediate concentrations, provided by hippocampal cells, and of pharmacological doses of estrogen on synapses and spines and on the expression of synaptic proteins. No effects of low concentrations were found. To study the effects of hippocampus-derived estradiol, we inhibited hippocampal estrogen synthesis by treatment of hippocampal cell cultures with letrozole, an aromatase inhibitor. Alternatively, we used siRNA against Steroidogenic acute regulatory protein (StAR). Spines, synapses, and synaptic proteins were significantly downregulated in response to letrozole and in siRNA-StAR transfected cells. ...
The hippocampus is well known for its roles in spatial navigation and memory, but it is organized into regions that have different connections and functional specializations. Notably, the region CA2 has a role in social and not spatial cognition, as is the case for the regions CA1 and CA3 that surround it. Here, we investigated the evolution of the hippocampus in terms of its size and organization in relation to the evolution of social and ecological variables in primates, namely home range, diet and different measures of group size. We found that the volumes within the whole cornu ammonis coevolve with group size, while only the volume of CA1 and subiculum can also be predicted by home range. On the other hand, diet, expressed as a shift from folivory towards frugivory, was shown to not be related to hippocampal volume. Interestingly, CA2 was shown to exhibit phylogenetic signal only against certain measures of group size, but not with ecological factors. We also found that sex differences in ...
TY - JOUR. T1 - Learning-induced afterhyperpolarization reductions in hippocampus are specific for cell type and potassium conductance. AU - de Jonge, M. C.. AU - Black, J.. AU - Deyo, R. A.. AU - Disterhoft, J. F.. PY - 1990/5. Y1 - 1990/5. N2 - Hippocampal slices were prepared from rabbits trained in a trace eye-blink conditioning task and from naive and pseudoconditioned controls. Measurements of the post-burst afterhyperpolarization (AHP), action potential, and other cellular properties were obtained from intracellular recordings of CA1 pyramidal (N=49) and dentate gyrus granule cells (N=52). A conditioning-specific reduction in the amplitude of the AHP was found in CA1 cells but not in dentate granule cells. This reduction in the AHP was apparent at 50 ms after the end of a depolarizing current pulse, and was maintained for at least 650 ms. Other measured cell characteristics (input resistance, resting membrane potential, action potential shape, inward rectification, spike threshold) were ...
In the present study, to better understand the role of different nitric oxide synthase (NOS) isoforms in hippocampus-dependent forms of learning, we examined the expression of neural, endothelial, and inducible NOS in the hippocampus of young-adult rats classified as poor and good learners on the basis of their performance in the partially baited 12-arm radial maze. Taking into consideration strain-dependent differences in learning skills and NOS expression, experiments were performed on two different lines of laboratory rats: the inbred Wistar (W) and the outcrossed Wistar/Spraque-Dawley(W/S) line. The hippocampal levels of NOS proteins were assessed by Western Blotting. In the present study, genetically more homogenous W rats showed a slower rate of learning compared to the genetically less homogenous outcrossed W/S rats. The deficient performance in the W rat group compared to outcrossed W/S rats, and in poor learners of both groups compared to good learners was due to a higher ...
Neuregulin 1 (NRG1) is a growth factor involved in neurodevelopment and plasticity. It is a schizophrenia candidate gene, and hippocampal expression of the NRG1 type I isoform is increased in the disorder. We have studied transgenic mice overexpressing NRG1 type I (NRG1(tg-type I)) and their wild-type littermates and measured hippocampal electrophysiological and behavioral phenotypes. Young NRG1(tg-type I) mice showed normal memory performance, but in older NRG1(tg-type I) mice, hippocampus-dependent spatial working memory was selectively impaired. Hippocampal slice preparations from NRG1(tg-type I) mice exhibited a reduced frequency of carbachol-induced gamma oscillations and an increased tendency to epileptiform activity. Long-term potentiation in NRG1(tg-type I) mice was normal. The results provide evidence that NRG1 type I impacts on hippocampal function and circuitry. The effects are likely mediated via inhibitory interneurons and may be relevant to the involvement of NRG1 in schizophrenia. However
The hippocampus is a section of the brain located below the cerebral cortex. It is a part of the limbic system and plays a part in memory.. The name derives from the fact that its curved shape resembles that of a sea horse (Greek: hippocampus).. There is substantial evidence (from animal studies and from patients with brain injury) that the hippocampus is crucial in the conversion of short term memory into long memory, though it is not yet clear how this occurs. Individuals whose hippocampus becomes damaged (for instance, those with Korsakoffs syndrome), whilst retaining the ability to access long-term memories from before their injury, become unable to form new ones. They can, however, learn new skills (such as playing a musical instrument) but will be totally unable to remember how they gained those skills.. There is also evidence, that the hippocampus is involved in storing unique information, as for example locations. Without a fully functional hippocampus a person may no more be able ...
Semantic Scholar extracted view of Implication of Cyclooxygenase-2 on Enhanced Proliferation of Neural Progenitor Cells in the Adult Mouse Hippocampus after Ischemia by 勉 佐々木
TY - JOUR. T1 - Nitric oxide-containing pyramidal neurons of the subiculum innervate the CA1 area. AU - Seress, László. AU - Ábrahám, Hajnalka. AU - Lin, Hong. AU - Totterdell, Susan. PY - 2002/10/31. Y1 - 2002/10/31. N2 - Neurons and axon terminals containing neuron-specific nitric oxide synthase (nNOS) were examined in the rat subiculum and CA1 area of Ammons horn. In the subiculum, a large subpopulation of the pyramidal neurons and non-pyramidal cells are immunoreactive for nNOS, whereas in the neighbouring CA1 area of Ammons horn only non-pyramidal neurons are labelled with the antibody against nNOS. In the pyramidal layer of the subiculum, nNOS-positive axon terminals form both asymmetric and symmetric synapses. In the adjacent CA1 area the nNOS-positive terminals that form symmetric synapses are found in all layers, whereas those terminals that form asymmetric synapses are only in strata radiatum and oriens, but not in stratum lacunosum-moleculare. In both the subiculum and CA1 area, ...
The hippocampus has long been understood to play a critical role in flexible relational learning, episodic memory, and navigation. More recently, a growing body of work implicates the hippocampus in value-based decision making. However, a dichotomy exists between research performed in different organisms and from distinct theoretical traditions. For instance, results in rodent models support an active role for the hippocampus in evaluating potential next-step actions and outcomes. Meanwhile, human research has mainly emphasized the role of the hippocampus in forming representations that may then support later decisions. Other divisions concern the nature of spatial versus more general relational processing, various algorithms for active sampling in support of decisions, and whether the hippocampus plays a part in tasks that require short-term memory or well-learned outcomes. These divergences are in part due to different experimental methods, but they also reveal fundamental gaps in the theory. ...
We determined whether basal excitatory synaptic transmission and long-term synaptic plasticity in the hippocampus were altered in MAGL−/− mice. fEPSPs were evoked by Schaffer collateral stimulation at 0.05 Hz, and the recording electrode was placed in the stratum radiatum of the CA1 region of the hippocampal slices prepared from MAGL+/+ and MAGL−/− mice. We first determined the I/O relationship between presynaptic axon fiber volley and fEPSP slopes by stimulating Schaffer collateral with incremental intensities. MAGL−/− mice did not exhibit significant changes in the slope of I/O curves compared with that of MAGL+/+ mice (n = 7-8 slices from 4 mice each; p , 0.05; data not shown). These results indicate that basal synaptic strength was not significantly changed in MAGL−/− mice.. Next, we compared the paired-pulse ratio (PPR), which is used as a measure of the probability of transmitter release. Synapses with high probability of transmitter release often display low PPR, whereas ...
Aging is characterized by an increased risk of cognitive deficits. It was shown using rodents that aging is associated with a significant reduction in the function of hippocampus, the brain structure important in forming spatial memories. Long-term potentiation (LTP) is an electrophysiologically induced phenomenon, whereby high frequency currents, artificially passed across specific axonal pathways, elicit a long-lasting change in the activity of the postsynaptic neurone. LTP induced in vivo in the adult rat hippocampus can last for months. Interestingly, LTP and learning activate common molecular mechanisms, which when impeded, can affect LTP persistence and memory. Thus, LTP serves as an excellent experimental model for studying memory-related mechanisms. It was previously established that LTP consists of distinct temporal phases, and that LTP-related gene expression changes in the early phase influence the late phase of LTP. Specifically, the robust expression of important immediate early ...
Purified Human Hippocampus Cytoplasmic Lysate from Creative Biomart. Human Hippocampus Cytoplasmic Lysate can be used for research.
Hippocampus hippocampus is a coastal marine seahorse that inhabits mud, sand, rubble and other habitats in the Northeast Atlantic. It occurs from the UK and the Netherlands to Senegal, including the Mediterranean Sea and coastal waters of the Azores, Madeira, and the Canary Islands. The species is under threat from being caught as bycatch in beach seines, gillnets, traps, and trawls. In addition its coastal habitats have suffered as a result of development and pollution. There is some evidence for a large (73%) decrease in population census size from one location (Ria Formosa, Portugal), but a lack of reliable survey data in many parts of this species range means that no consistent trends have been observed across the species range. Thus, based on a lack of data the extinction risk of this species cannot be reliably categorised on a global level. Hippocampus hippocampus is therefore listed as Data Deficient ...
The CA2 region of the mammalian hippocampus is a unique region with its own distinctive properties, inputs and pathologies. Disruption of inhibitory circuits in this region appears to be linked with the pathology of specific psychiatric disorders, promoting interest in its local circuitry, its role in hippocampal function and its dysfunction in disease. In previous studies, CA2 interneurons, including a novel subclass of CA2 dendrite-preferring interneurons that has not been identified in other CA regions, have been shown to display physiological, synaptic and morphological properties unique to this sub-field and may therefore play a crucial role in the hippocampal circuitry. The distributions of immuno-labeled interneurons in dorsal CA2 were studied and compared with those of interneurons in CA1 and CA3. Like those in CA1 and CA3, the somata of CA2 parvalbumin-immunoperoxidase-labeled interneurons were located primarily in Stratum Pyramidale (SP) and Stratum Oriens (SO), with very few cells in Stratum
Stažení (download) souboru Family Guy - 08x10 - Big Man on Hippocampus.avi, Velikost 182340402|bytes, Typ: avi, Délka: 20:55, Bitrate:1 127,13 kB/s, Video kodek: XviD MPEG-4 (www.xvid.org), Rozlišení: 512 x 384, Video FPS: 24, Audio kodek: mp3, Vzorkování: 48000, Audio kanálů: 2, Typ audia: joint stereo
et_pb_section bb_built=1][et_pb_row][et_pb_column type=4_4][et_pb_text _builder_version=3.0.82 background_layout=light border_style=solid box_shadow_position=outer]. Lets get into the technical stuff. The prefrontal cortex - the part of your brain responsible for everything from cognition to decision-making - is flanked by both the hippocampus and the amygdala. Both pay integral roles in learning, but they react very specifically in terms of modlette learning.. The hippocampus is your brains message centre: It filters through information and makes quick judgements based on how important that information actually is. The hippocampus is then responsible for sending the important stuff to the long-term memory for storage and later retrieval.. Information is only held within the working memory of the hippocampus for about 20 minutes. If data is not converted to a long term memory by then, its usually discarded by the brain and no longer available for recall or future ...
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Looking for hippocampus minor? Find out information about hippocampus minor. A ridge that extends over the floor of the descending horn of each lateral ventricle of the brain. A genus of marine fishes in the order Gasterosteiformes... Explanation of hippocampus minor
Hippocampal responses to electrical stimulation of the prepyriform cortex in the cat were studied both in acute experiments under halothane anesthesia and in awake cats with chronically indwelling electrodes. Analysis of field potentials and unit activity indicated the extent to which different hippocampal subareas were activated, the laminar level at ... read more which the synaptic action took place and the dynamics of the evoked responses. It was found that: (1) the main generator of evoked responses in the hippocampus upon prepyriform cortex stimulation is localized in the fascia dentata and CA3 (CA1 pyramidal cells, and probably also subiculum cells, are activated but in a lesser degree); (2) the initial synaptic activity takes place at the most distal part of the dendrites of fascia dentata granule cells and CA3 pyramidal cells; and (3) this synaptic activity corresponds to an EPSP that leads to a transient increase in the firing rate of the hippocampal units, which is often followed by a ...
I am super-jazzed that my essay, Future Perfect, will be published in the August 2017 edition of Hippocampus Magazine. I love Hippocampus, and I am honored to be a contributor.. In Future Perfect, during a chance encounter in the grocery store, I grapple with what the future will look like for my family. I started this essay years ago, and it needed a little time to germinate. I am glad it has found a home with Hippocampus.. Oh! And BTW, if you dont know about HippoCamp, you should check it out. Its a great CNF conference put on by Hippocampus that takes place in Lancaster, PA. I went last year, and Ill be back again for this one. Check out those keynotes! (And theyre not even the best part of the conference!) Heck, I just realized I even am wearing the shirt from last years conference as I write this.. ...
BioAssay record AID 194727 submitted by ChEMBL: Compound was tested for the selective increase in K+ stimulated AcCh release in brain region of hippocampus at 10 uM concentration.
RESULTS: Both hippocampal volumes were small in patients with MDD compared with healthy controls, and the right hippocampal volume was negatively correlated with the number of episodes at marginal significance. Regional shape contractions were found in the ambient gyrus, basal hippocampal head, posterior subiculum, and dorsal hippocampus of the left hemisphere. The right hippocampus showed a similar pattern but was less atrophic compared with the left hippocampus. A negative correlation was found between the HDRS and shape deformation in the CA3, ambient gyrus, posterior subiculum, and gyrus fasciolaris of the left hippocampus. ...
Dietary effects of arachidonate-rich fungal oil and fish oil on murine hepatic and hippocampal gene expression Roberts, Matthew A; Berger, Alvin; Bruce German, J; Mutch, David M ...
To date, researchers have developed various animal models of Alzheimers disease (AD) to investigate its mechanisms and to identify potential therapeutic treatments. A widely recognized model that mimics the pathology of human sporadic AD involves intracerebroventricular (ICV) injection with streptozotocin (STZ). However, ICV injections are an invasive approach, which creates limitations in generalizing the results. In this study, we produced a rodent model of AD using STZ (3 mg/kg) injection via the cisterna magna (CM) once every week for 4 weeks, and analyzed at 4 weeks and 16 weeks after final injection. In the CM-STZ rodent model of AD, we observed increase in extracellular amyloid-beta (Aβ) deposition and decrease and abnormal morphology of post-synaptic protein, PSD95 in 16 weeks STZ-injected group. The model developed using our less-invasive method induced features of AD-like pathology, including significantly increased extracellular amyloid-beta deposition, and decreased synaptic protein in the
Binding. I think its important to distinguish between the type of binding that may occur in the hippocampus and the binding involved in, say, recognizing a novel configural stimulus (e.g., a word or face) in order to take an action. Although these two types of binding may use similar computation or at least yield similar results, it may be misleading to use one term for both processes. I think that when most people say binding, they are referring to the latter process.. Certainly, it seems as though the hippocampus is *able* to bind features, but cant people with hippocampal damage still bind, perceive, and make decisions on complex configural stimuli?. What about Hippocampal Consolidation?. In the studies you cited above, the increased activation of the hippocampus for novel objects during the working memory delays could simply reflect the fact that novel objects are ones that have yet to be learned, i.e., have not yet been consolidated. As per hippocampal consolidation theory, a ...
Although originally cloned from rat brain, the P2X7 receptor has only recently been localized in neurones, and functional responses mediated by these neuronal P2X7 receptors (P2X7 R) are largely unknown. Here we studied the effect of P2X7 R activation on the release of neurotransmitters from superfused rat hippocampal slices. ATP (1-30 mm) and other ATP analogues elicited concentration-dependent [3 H]GABA outflow, with the following rank order of potency: benzoylbenzoylATP (BzATP) | ATP | ADP. PPADS, the non-selective P2-receptor antagonist (3-30 microm), Brilliant blue G (1-100 nm) the P2X7 -selective antagonist and Zn2+ (0.1-30 microm) inhibited, whereas lack of Mg2+ potentiated the response by ATP. In situ hybridization revealed that P2X7 R mRNA is expressed in the neurones of the cell body layers in the hippocampus. P2X7 R immunoreactivity was found in excitatory synaptic terminals in CA1 and CA3 region targeting the dendrites of pyramidal cells and parvalbumin labelled structures. ATP (3-30 microm)
Disinhibition is a widespread circuit mechanism for information selection and transfer. In the hippocampus, disinhibition of principal cells is provided by the interneuron-specific interneurons that express the vasoactive intestinal polypeptide (VIP-IS) and innervate selectively inhibitory interneurons. By combining optophysiological experiments with computational models, we determined the impact of synaptic inputs onto the network state-dependent recruitment of VIP-IS cells. We found that VIP-IS cells fire spikes in response to both the Schaffer collateral and the temporoammonic pathway activation. Moreover, by integrating their intrinsic and synaptic properties into computational models, we predicted recruitment of these cells between the rising phase and peak of theta oscillation and during ripples. Two-photon Ca2+-imaging in awake mice supported in part the theoretical predictions, revealing a significant speed modulation of VIP-IS cells and their preferential albeit delayed recruitment ...
Disinhibition is a widespread circuit mechanism for information selection and transfer. In the hippocampus, disinhibition of principal cells is provided by the interneuron-specific interneurons that express the vasoactive intestinal polypeptide (VIP-IS) and innervate selectively inhibitory interneurons. By combining optophysiological experiments with computational models, we determined the impact of synaptic inputs onto the network state-dependent recruitment of VIP-IS cells. We found that VIP-IS cells fire spikes in response to both the Schaffer collateral and the temporoammonic pathway activation. Moreover, by integrating their intrinsic and synaptic properties into computational models, we predicted recruitment of these cells between the rising phase and peak of theta oscillation and during ripples. Two-photon Ca2+-imaging in awake mice supported in part the theoretical predictions, revealing a significant speed modulation of VIP-IS cells and their preferential albeit delayed recruitment ...
Gender differences in spatial memory favoring men are frequently reported, and the involvement of the hippocampus in these functions is well-established. However, little is known of whether this behavioral gender difference is mirrored in a gender difference in hippocampal function. Here we assessed hippocampal activity, using functional MRI, while 24 men and women moved through three-dimensional virtual mazes (navigation phase) of varying length, and at the end-point estimated the direction of the starting-point (pointing phase). Men were indeed more accurate than women at estimating direction, and this was especially true in longer mazes. Both genders activated the posterior hippocampus throughout the whole task. During the navigation phase, men showed a larger activation in the right hippocampus than women, while in the pointing phase, women showed a larger activation in the left hippocampus than men. Right-lateralized activation during the navigation phase was associated with greater task ...
During development, activity-dependent processes increase the specificity of neural responses to stimuli, but the role that this type of process plays in adult plasticity is unclear. We examined the dynamics of hippocampal activity as animals learned about new environments to understand how neural selectivity changes with experience. Hippocampal principal neurons fire when the animal is located in a particular subregion of its environment, and in any given environment the hippocampal representation is sparse: less than half of the neurons in areas CA1 and CA3 are active whereas the rest are essentially silent. Here we show that different dynamics govern the evolution of this sparsity in CA1 and upstream area CA3. CA1, but not CA3, produces twice as many spikes in novel compared with familiar environments. This high rate firing continues during sharp wave ripple events in a subsequent rest period. The overall CA1 population rate declines and the number of active cells decreases as the environment ...
In the hippocampus, a structure extremely well-known for its role in learning and memory, the answer for why there would be a need for newborn neurons in the adult might seem a little more straightforward. And, as it turns out, it appears that newborn neurons in the adult hippocampus are required for the formation of new memories. But, interestingly, the production of too many newborn neurons in the hippocampus may paradoxically induce forgetting. In a paper recently published in Science, Aker and colleagues suggest an explanation for the phenomenon of infantile amnesia. Dont vividly remember the first few years of your life? Based on the interesting evidence presented in the paper, the authors suggest that the production of new cells within the hippocampus actually regulates forgetting. When we are newborns, the process of neurogenesis is occurring at an alarming rate and because of this, we are not able to retain any of our first memories during early life. I found this particular study to be ...
Brain and hippocampus. Coloured magnetic resonance imaging (MRI) scan of a coronal section through the head of a healthy 30-year-old, showing the location of the hippocampus (highlighted). The hippocampus is part of the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory, as well as spatial navigation. - Stock Image C023/9772
Hi all there. I am new in cell culture and dont know anything about cell shape. My cells are spherical after isolation and their shape dont change even after 3-4 days. I like to know the normal pattern of hippocampal cell growth in cell culture. Meaning that how much time last to cells getting their projections ...
For other uses, see Hippocampus (disambiguation). Brain: Hippocampus The hippocampus is located in the medial temporal lobe of the brain. In this lateral view of the human brain, the frontal lobe is at le
Hippocampus can be related to limbic system of the brain and it has a significant role in not only maintaining long term memory but also in spatial navigation ...
Looking for online definition of pyramidal layer in the Medical Dictionary? pyramidal layer explanation free. What is pyramidal layer? Meaning of pyramidal layer medical term. What does pyramidal layer mean?
Fig. 6 HSP105-siRNA in HT22 cells or stressed mouse brain decreased BDNF levels and abolished antidepressant effects.. (A) Level of HSP105 mRNA in HT22 cells (ANOVA, F2,13 = 544.1, n = 5 to 6). (B) Level of BDNF mRNA in HT22 cells (ANOVA, F2,13 = 10.74, n = 5 to 6). (C) The level of HSP105 protein in the hippocampus was detected by Western blotting (n = 3). (D) Immobility times in the forced swim test (ANOVA, F2,11 = 6.03). (E) Immobility times in the tail suspension test (ANOVA, F2,11 = 15.02). (F) Social interaction rate in the interaction test (ANOVA, F2,11 = 5.00). (G) Sucrose preference and total fluid intake in the sucrose preference test. (H) Level of BDNF mRNA and protein in the mouse hippocampus (ANOVA, F2,11 = 4.54 and F2,12 = 5.41, respectively) (n = 4 to 5 animals per group). Each bar indicates the mean ± SEM. GGA + NTC, GGA with nontargeting control; GGA + HSP105-siRNA, GGA with HSP105-siRNA treatment. Statistically different groups are indicated by letters. ...
TY - GEN. T1 - Long-range temporal correlations in the spontaneous in vivo activity of interneuron in the mouse hippocampus. AU - Guo, Sheng Bo. AU - Wang, Ying. AU - Yan, Xing. AU - Lin, Longnian. AU - Tsien, Joseph Zhuo. AU - Huang, De Shuang. PY - 2007. Y1 - 2007. N2 - The spontaneous in vivo firings of neuron in mouse hippocampus are generally considered as neuronal noise, where there is no any correlation in the inter-spike interval (ISI) sequences. In the present study, we investigate the nature of the ISI sequences of neuron in CAl area of mouse hippocampus. By using the detrended fluctuation analysis (DFA), we calculated the fluctuation or scaling exponent of the ISI sequences. The results indicated that there exists the long-range power-law correlation over large time scale in the ISI sequences. To further investigate the long-range correlation of ISI, we studied the long-range correlation of ISI sequences from different types of neurons in mouse hippocampus, which are four types of ...
COMT polymorphism regulates the hippocampal subfield volumes in first-episode, drug-naive patients with major depressive disorder
Hippocampal neurons are vulnerable to injury, as indicated by the prevalence of learning and memory deficits following traumatic brain injury. Research indicates that proliferation of neural precursor cells increases following brain injury, which implies that there is an endogenous response in the hippocampus to replenish neurons and restore cognitive function. Studies show that mitogenic growth factors may drive this proliferative response; one of which is epidermal growth factor. Because adults and the elderly manifest the most enduring deficits following TBI, it is critical to investigate how EGF expression following injury may relate to injury-induced cell proliferation and the degree of cognitive recovery observed with aging. In the current study, we assessed the temporal and spatial expression of EGF in the injured hippocampus with age. Our results suggest that EGF expression increases following TBI, and this increase is more significant in the younger brain. Additionally, we investigated the
Memory formation and recall depend on a complex circuit that includes the hippocampus and associated cortical regions. The goal of this thesis was to understand how two of the cortical connections, the medial entorhinal cortex (MEC) and medial prefrontal cortex (mPFC), influence spatial and nonspatial activity in the hippocampus. Cells in the MEC exhibit prominent spatially selective activity and have been hypothesized to drive place representation in the hippocampus. In Experiment 1 the MEC was transiently inactivated using the inhibitory opsin ArchaerhodopsinT (ArchT), and simultaneous recordings from CA1 were made as rats ran on an elliptical track. In response to MEC disruption some cells in the hippocampus shifted the preferred location of activity, some changed firing rate and others were unaffected. The new representation that developed following MEC disruption remained stable despite the fact that inhibition was transient. If the MEC is the source of spatial activity in the hippocampus ...
In hippocampal neurons, AMPA receptors (AMPARs) mediate fast excitatory postsynaptic responses at glutamatergic synapses, and are involved in various forms of synaptic plasticity. Dendritic local protein synthesis of selected AMPAR subunit mRNAs is considered an additional mechanism to independently and rapidly control the strength of individual synapses.. We have used fluorescent in situ hybridization and immunocytochemistry to analyze the localization of AMPAR subunit (GluA1-4) mRNAs and their relationship with the translation machinery in principal cells and interneurons of the adult rat hippocampus. The mRNAs encoding all four AMPAR subunits were detected in the somata and dendrites of CA3 and CA1 pyramidal cells and those of six classes of CA1 γ-aminobutyric acid (GABA)ergic interneurons. GluA1-4 subunit mRNAs were highly localized to the apical dendrites of pyramidal cells, whereas in interneurons they were present in multiple dendrites. In contrast, in the dentate gyrus, GluA1-4 subunit ...
TY - JOUR. T1 - Appearance of amyloid β-like substances and delayed-typed apoptosis in rat hippocampus CA1 region through aging and oxidative stress. AU - Fukui, Koji. AU - Takatsu, Hirokatsu. AU - Shinkai, Tadashi. AU - Suzuki, Shozo. AU - Abe, Kouichi. AU - Urano, Shiro. PY - 2005/1/1. Y1 - 2005/1/1. N2 - To elucidate whether oxidative stress induces cognitive deficit, and whether nerve cells in the hippocampus, which modulates learning and memory functions in the brain, are damaged by oxidative stress and during aging, the influence of hyperoxia as oxidative stress on either the cognitive function of rats or the oxidative damage of nerve cells was investigated. Young rats showed better learning ability than both old rats and vitamin E-deficient young rats. Vitamin E- supplemented young rats showed similar ability to young control rats. After they learned the location of the platform in the Morris water maze test, the young rats and vitamin E-supplemented young rats were subjected to ...
TY - JOUR. T1 - Analysis of current fluctuations during after-hyperpolarization current in dentate granule neurones of the rat hippocampus. AU - Valiante, Taufik A.. AU - Abdul-Ghani, Muhammad A.. AU - Carlen, Peter L.. AU - Pennefather, Peter. PY - 1997/2/15. Y1 - 1997/2/15. N2 - We have studied macroscopic current fluctuations associated with the after-hyperpolarization current (I(AHP)) that follows a 200 ms voltage-clamp step to 0 mV in dentate granule (DG) neurones of the rat hippocampus. This maximally effective stimulus produced a peak I(AHP) of 205 ± 20 pA. Background noise was minimized by using the whole-cell single-electrode voltage-clamp configuration. 2. Conventional current-variance analysis was performed on I(AHP) to obtain estimates of the unitary AHP channel current (i) and the maximal attainable AHP current (I(max)). A second approach, utilizing changes in the power spectrum of I(AHP) noise during the decay of I(AHP), was employed to yield an independent estimate of I(max) as ...
The effect of quinine on pyramidal cell intrinsic properties, extracellular potassium transients, and epileptiform activity was studied in vitro using the rat hippocampal slice preparation. Quinine enhanced excitatory post-synaptic potentials and decreased fast- and slow-inhibitory post-synaptic potentials. Quinine reduced the peak potassium rise following tetanic stimulation but did not affect the potassium clearance rate. Epileptiform activity induced by either low-Ca(2+) or high-K(+) artificial cerebrospinal fluid (ACSF) was suppressed by quinine. The frequency of spontaneous inter-ictal bursting induced by picrotoxin, high-K(+), or 4-aminopyridine was significantly increased. In normal ACSF, quinine did not affect CA1 pyramidal cell resting membrane potential, input resistance, threshold for action potentials triggered by intracellular or extracellular stimulation, or the orthodromic and antidromic evoked population spike amplitude. The main effects of quinine on intrinsic cell properties were to
In this study, the impact of membrane-associated factors on axonal outgrowth during development and following lesion was examined. We studied the maturation-dependent features of membrane-associated molecules in the hippocampus with the stripe assay for guidance activity and with the outgrowth assay for outgrowth-supporting activity. We could show that entorhinal axons discriminate between their proper target area, the hippocampus, and control regions which do not receive synaptic connections from the entorhinal cortex, and preferred to grow on hippocampal membranes. Further, we examined guidance preferences of entorhinal neurites on hippocampal membranes in different developmental stages. The choice behavior of entorhinal neurites for hippocampal membranes temporally correlates with the ingrowth of the perforant path into the hippocampus and with the stabilization of this brain area in vivo, and further indicate the transient presence of membrane-associated guidance cues in the hippocampus. One ...
Theta activity is one of the most prominent rhythms in the brain and appears to be conserved among mammals. These 4-12 Hz oscillations have been predominantly studied in the dorsal hippocampus where they are correlated with a broad range of voluntary and exploratory behaviors. Theta activity has been also implicated in a number of mnemonic processes, long-term potentiation (LTP) induction and even acting as a global synchronizing mechanism. Moving along the dorso-ventral axis theta activity is reduced in power and desynchronized from the dorsal part. However, theta activity can also be generated in the ventral hippocampus itself during anxiety- and fear-related behaviors. Until now it was unknown which hippocampal cell population was capable to generate theta activity and it was controversial if its origin was local, in the hippocampus, or driven by other brain regions. In this thesis I present compelling in vitro and in vivo evidence that a subpopulation of OLM interneurons (defined by the ...
Hippocampus Anatomy Mri - See more about Hippocampus Anatomy Mri, hippocampus anatomy mri, hippocampus anatomy mri axial, hippocampus anatomy mri radiographics, hippocampus anatomy mri radiology
Hippocampus Anatomy Mri - See more about Hippocampus Anatomy Mri, hippocampus anatomy mri, hippocampus anatomy mri axial, hippocampus anatomy mri radiographics, hippocampus anatomy mri radiology
Vasopressin (VP) is axonally distributed in many brain structures, including the ventral hippocampus. Picogram quantities of VP injected into the hippocampus improve the passive avoidance response of rats, presumably by enhancing memory processes. Vasopressin is metabolized by the brain tissue into shorter peptides, such as [pGlu4r,Cyt6]VP(4 9[ and [pGIu4,Cyt6,]VP(4 8), which preserve ... read more the behavioral activity but lose the peripheral activities of the parent hormone. Using brain slices, we investigated whether VP or VP(4 8) affects excitatory postsynaptic potentials (EPSPs) and/or membrane responses to depolarization in neurons of the CA 1 /subiculum of the ventral hippocampus. The EPSPs were evoked by stimulating the stratum radiatum of the CAI field; the membrane responses were elicited by current injections. Exposure of slices for 15 min to 0.1 nM solution of these peptides resulted in an increase in the amplitude and slope of the EPSPs in 21 neurons (67%) tested. No consistent ...
The mRNAs encoding kainic acid (KA) preferring glutamate receptor subunits (GluR5-7, KA1 and KA2) are differentially expressed in rat brain. We have used regional and cellular in situ hybridization histochemistry with subunit-specific 35S-labelled oligodeoxyribonucleotides to examine these mRNAs in adult human hippocampus, neocortex and cerebellum. GluR5 mRNA was detected only in Purkinje cells and a few scattered hippocampal neurons. GluR6 mRNA was relatively abundant in all areas, notably in dentate gyrus, pyramidal neurons of CA3, and cerebellar granule cells, as well as being present in superficial and deep laminae of the neocortex. Moderate signal for GluR7 mRNA was seen in deep laminae of the neocortex with a weak signal in the dentate gyrus; in dipped sections GluR7 mRNA was also apparent over some pyramidal and non-pyramidal cells in hippocampus and over putative cerebellar stellate/basket cells. KA1 mRNA was detected in the dentate gyrus but not reliably elsewhere. The expression profile and
Theta activity is one of the most prominent rhythms in the brain and appears to be conserved among mammals. These 4-12 Hz oscillations have been predominantly studied in the dorsal hippocampus where they are correlated with a broad range of voluntary and exploratory behaviors. Theta activity has been also implicated in a number of mnemonic processes, long-term potentiation (LTP) induction and even acting as a global synchronizing mechanism. Moving along the dorso-ventral axis theta activity is reduced in power and desynchronized from the dorsal part. However, theta activity can also be generated in the ventral hippocampus itself during anxiety- and fear-related behaviors. Until now it was unknown which hippocampal cell population was capable to generate theta activity and it was controversial if its origin was local, in the hippocampus, or driven by other brain regions. In this thesis I present compelling in vitro and in vivo evidence that a subpopulation of OLM interneurons (defined by the ...
Gliosis is one of the main morphological correlates of epilepsy. It is presented predominantly by proliferation and hypertrophy of astrocytes and activated microglia (macrophages) and is most characteristic to those areas of the epileptogenic zones, where the loss of neurons is significant. One of such structures is the hippocampus, the sclerosis of which develops already at the early stages of epileptogenesis. Using the slides stained with cresylviolet, the quantitative analysis of gliocytes and of macrogliocyte-neuronal ratio was performed in all the areas of the hippocampus 14 and 30 days after electrical kindling. After both time intervals, the decrease of the number of neurons and the increase of the number of gliocytes were found in all the regions of the hippocampus. After 14 days the changes of gliocytes were particularly significant in the radial and oriental layers of the Ammons horn, after 30 days they were also pronounced in CA3 pyramidal cell layer of and in hilus. Thus, ...
The effects of adenosine on inhibitory synaptic transmission in area CA1 were examined using the rat hippocampal slice preparation and intracellular recording. Adenosine did not change fast inhibitory synaptic potentials (IPSPs) but depressed late IPSPs evoked by direct activation of interneurons in the presence of 6,7-dinitroquinoxaline-2,3-dione (DNQX) and D,L-2-amino-5-phosphonovalerate (APV). Directly activated IPSPs were unchanged by the selective adenosine A1 receptor antagonist 8-cyclopentyltheophylline (CPT), but CPT reversed hyperpolarization and depression of late IPSPs produced by adenosine. These results indicate that adenosine depresses disynaptic IPSPs in area CA1 by decreasing synaptic activation of inhibitory neurons ...
TY - JOUR. T1 - Arcadlin is a neural activity-regulated cadherin involved in long term potentiation. AU - Yamagata, Kanato. AU - Andreasson, Katrin I.. AU - Sugiura, Hiroko. AU - Maru, Eiichi. AU - Dominique, Muller. AU - Irie, Yasuyuki. AU - Miki, Naomasa. AU - Hayashi, Yokichi. AU - Yoshioka, Masatomo. AU - Kaneko, Kenya. AU - Kato, Hiroshi. AU - Worley, Paul F.. PY - 1999/7/2. Y1 - 1999/7/2. N2 - Neural activity results in long term changes that underlie synaptic plasticity. To examine the molecular basis of activity-dependent plasticity, we have used differential cloning techniques to identify genes that are rapidly induced in brain neurons by synaptic activity. Here, we identify a novel cadherin molecule Arcadlin (activity-regulated cadherin-like protein), arcadlin mRNA is rapidly and transiently induced in hippocampal granule cells by seizures and by N-methyl-D-aspartate-dependent synaptic activity in long term potentiation. The extracellular domain of Arcadlin is most homologous to ...
Adult hippocampal neurogenesis is a process involving the continuous generation of newborn neurons in the hippocampus of adult animals. Mounting evidence has suggested that hippocampal neurogenesis contributes to some forms of hippocampus-dependent learning and memory; however, the detailed mechanism concerning how this small number of newborn neurons could affect learning and memory remains unclear. In this review, we discuss the relationship between adult-born neurons and learning and memory, with a highlight on recently discovered potential roles of neurogenesis in pattern separation and forgetting ...
Traumatic brain injury (TBI) is a major cause of death and disability. However, the molecular events contributing to the pathogenesis are not well understood. Mitochondria serve as the powerhouse of cells, respond to cellular demands and stressors, and play an essential role in cell signaling, differentiation, and survival. There is clear evidence of compromised mitochondrial function following TBI; however, the underlying mechanisms and consequences are not clear. MicroRNAs (miRNAs) are small non-coding RNA molecules that regulate gene expression post-transcriptionally, and function as important mediators of neuronal development, synaptic plasticity, and neurodegeneration. Several miRNAs show altered expression following TBI; however, the relevance of mitochondria in these pathways is unknown. Here, we present evidence supporting the association of miRNA with hippocampal mitochondria, as well as changes in mitochondria-associated miRNA expression following a controlled cortical impact (CCI) injury in
for Doublecortin and Neuronal Nuclei (DCX/ NeuN),Glial fibrillary acid protein and Neuronal Nuclei (GFAP/ NeuN). Our data indicate that the yaks hippcampus mainly contains dentate gyrus and hippocampus proper,and both of them stratify clearly. Granular cells,mossy cells and pyramidal cells are the three major cell types of the hippocampus formation. The soma of pyramidal cells in the CA3 region is much bigger than in the CA1 region,while the latter has an average length of apical dendrites longer than the former. The pyramidal cells contain distinctive sublayers in the CA1 regions,but form a close uniform layer in the CA3 region. The somas of most DCX-positive cells,which distribute individually or in clusters,mainly locate in the deepest part of the granule cell layer closing to the hilus. A layer of GFAP-expressing radial glia-like cells is observed in the subgranular zone of the dentate gyrus,and its cytoplasms and single polarity processes,but not nucleus,are GFAP-positive. A large number ...
TY - JOUR. T1 - Distinct epigenetic and gene expression changes in rat hippocampal neurons after Morris water maze training. AU - Carter, Sylvia D. AU - Mifsud, Karen R. AU - Reul, Johannes M H M. PY - 2015/6/16. Y1 - 2015/6/16. N2 - Gene transcription and translation in the hippocampus is of critical importance in hippocampus-dependent memory formation, including during Morris water maze (MWM) learning. Previous work using gene deletion models has shown that the immediate-early genes (IEGs) c-Fos, Egr-1, and Arc are crucial for such learning. Recently, we reported that induction of IEGs in sparse dentate gyrus neurons requires ERK MAPK signaling and downstream formation of a distinct epigenetic histone mark (i.e., phospho-acetylated histone H3). Until now, this signaling, epigenetic and gene transcriptional pathway has not been comprehensively studied in the MWM model. Therefore, we conducted a detailed study of the phosphorylation of ERK1/2 and serine10 in histone H3 (H3S10p) and induction of ...
TY - JOUR. T1 - Endogenous serotonin inhibits epileptiform activity in rat hippocampal CA1 neurons via 5-hydroxytryptamine(1A) receptor activation. AU - Lu, Kwok-Tung. AU - Gean, P. W.. PY - 1998/6/8. Y1 - 1998/6/8. N2 - The modulatory effects of endogenous serotonin on the synaptic transmission and epileptiform activity were studied in the rat hippocampus with the use of extracellular and intracellular recording techniques. Field excitatory postsynaptic potential was reversibly depressed by serotonin in a concentration-dependent manner. Intracellular recordings revealed that serotonin-mediated synaptic depression was unaffected by extracellular Ba2+ or intracellular application of Cs+ while the postsynaptic hyperpolarizing effect was completely blocked. Epileptiform activity induced by picrotoxin (50 μM), a GABA(A) receptor antagonist, was also dose-dependently suppressed by serotonin. The antiepileptic effect was mimicked by 5- hydroxytryptamine(1A) agonist and was blocked by ...
The formation and deposition of tau protein aggregates is proposed to contribute to cognitive impairments in dementia by disrupting neuronal function in brain regions, including the hippocampus. We used a battery of in vivo and in vitro electrophysiological recordings in the rTg4510 transgenic mouse model, which overexpresses a mutant form of human tau protein, to investigate the effects of tau pathology on hippocampal neuronal function in area CA1 of 7- to 8-month-old mice, an age point at which rTg4510 animals exhibit advanced tau pathology and progressive neurodegeneration. In vitro recordings revealed shifted theta-frequency resonance properties of CA1 pyramidal neurons, deficits in synaptic transmission at Schaffer collateral synapses, and blunted plasticity and imbalanced inhibition at temporoammonic synapses. These changes were associated with aberrant CA1 network oscillations, pyramidal neuron bursting, and spatial information coding in vivo. Our findings relate tauopathy-associated ...
The use of computational models has been invaluable for exploring the link between neurons and behavior, enabling hypothetical mechanisms to be defined precisely and examined quantitatively. This chapter reviews many of these models, including models of spatial functions, models of more general associative mnemonic functions, models that stress feedforward processing through the hippocampal system, and those stressing recurrent processing within it. Spatial models are reviewed first, as they are most firmly rooted in the known electrophysiology of the region. These models cover both the representation of the animals spatial location and orientation and the use of this information in spatial navigation. The models of mnemonic function, specifically associative or episodic memory, follow from Marrs seminal 1971 model. This model is used as a generic framework in which to consider the various subsequent developments to it. Finally, the chapter reviews those models attempting to bring together the ...
OKeefe and Recce [1993] Hippocampus 3:317-330 described an interaction between the hippocampal theta rhythm and the spatial firing of pyramidal cells in the CA1 region of the rat hippocampus: they found that a cells spike activity advances to earlier phases of the theta cycle as the rat passes through the cells place field. The present study makes use of large-scale parallel recordings to clarify and extend this finding in several ways: 1) Most CA1 pyramidal cells show maximal activity at the same phase of the theta cycle. Although individual units exhibit deeper modulation, the depth of modulation of CA1 population activity is about 50%. The peak firing of inhibitory interneurons in CA1 occurs about 60 degrees in advance of the peak firing of pyramidal cells, but different interneurons vary widely in their peak phases. 2) The first spikes, as the rat enters a pyramidal cells place field, come 90 degrees-120 degrees after the phase of maximal pyramidal cell population activity, near the phase where
The Hippocampus Book. Andersen, Per. 1stPublisher: Oxford University Press, USAFormat: Hardcover. The hippocampus is one of a group of remarkable structures embedded within the medial temporal lobe of the brain. Long known to be important for memory, it has been a prime focus of neuroscience research for many years. The Hippocampus Book promises to facilitate developments in the field in a major way by bringing together, for the first time, contributions by leading international scientists working on hippocampal anatomy, physiology, and function. This authoritative volume offers the most comprehensive, up-to-date account of what the hippocampus does, how it does it and what happens when things go wrong. At the same time, it illustrates how research focusing on this single brain structure has revealed principles of wider generality for the whole brain in relation to anatomical connectivity, synaptic plasticity, cognition and behaviour, and computational algorithms. Well-organised in its ...
The hippocampal dentate gyrus in the adult mammalian brain contains neural stem/progenitor cells (NS/PCs) capable of generating new neurons, i.e., neurogenesis. Most drugs of abuse examined to date decrease adult hippocampal neurogenesis, but the effects of cannabis (marijuana or cannabinoids) on hippocampal neurogenesis remain unknown. This study aimed at investigating the potential regulatory capacity of the potent synthetic cannabinoid HU210 on hippocampal neurogenesis and its possible correlation with behavioral change. We show that both embryonic and adult rat hippocampal NS/PCs are immunoreactive for CB1 cannabinoid receptors, indicating that cannabinoids could act on CB1 receptors to regulate neurogenesis. This hypothesis is supported by further findings that HU210 promotes proliferation, but not differentiation, of cultured embryonic hippocampal NS/PCs likely via a sequential activation of CB1 receptors, Gi/o proteins, and ERK signaling. Chronic, but not acute, HU210 treatment promoted ...
Damage to this area of the brain can limit the formation of new memories while leaving distant memories intact. The hippocampus is sensitive to oxygen deprivation and may become damaged in situations like near drowning, heart attack, respiratory failure, sleep apnea and carbon monoxide poisoning. Frequent seizures could also impact the function of the hippocampus and generally is the first part of the brain impacted by Alzheimers disease. Marijuana abuse can also damage the hippocampus and alcohol use shuts down the hippocampus. ...
Rationale - Cannabis use is associated with neuroanatomical alterations in the hippocampus. While the hippocampus is composed of multiple subregions, their differential vulnerability to cannabis dependence remains unknown. Objectives - The objective of the study is to investigate gray matter alteration in each of the hippocampal subregions (presubiculum, subiculum, cornu ammonis (CA) subfields CA1-4, and dentate gyrus (DG)) as associated with cannabis use and dependence. Methods - A total of 35 healthy controls (HC), 22 non-dependent (CB-nondep), and 39 dependent (CB-dep) cannabis users were recruited. We investigated group differences in hippocampal subregion volumes between HC, CB-nondep, and CB-dep users. We further explored the association between CB use variables (age of onset of regular use, monthly use, lifetime use) and hippocampal subregions in CB-nondep and CB-dep users separately. Results - The CA1, CA2/3, CA4/DG, as well as total hippocampal gray matter were reduced in volume in CB-dep but
The effects of the co-agonist of the N-methyl-d-aspartate receptor (NMDAr) d-serine on glutamatergic neurotransmission and synaptic potentiation were studied in the CA1 hippocampal field of young (3-5 months old) and aged (25-27 months old) Sprague-Dawley rats using ex vivo extracellular electrophysiological recording techniques. Exogenous d-serine depressed fast neurotransmission mediated by the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid/kainate subtype of glutamate receptors in young but not in aged rats by acting on inhibitory glycinergic interneurons. In contrast, d-serine dose-dependently enhanced NMDAr-mediated synaptic responses in both groups of animals, but with a larger magnitude in aged rats, thus preventing the age-related decrease in NMDAr activation. d-serine also increased the magnitude of long-term potentiation in aged but not in young rats. Finally, d-serine levels were dramatically reduced in hippocampal tissues of aged rats. Taken together, these results indicate a ...
Prenatal stress (PS) has been shown to influence the development of the fetal brain and to increase the risk for the development of psychiatric disorders in later life. Furthermore, the variation of human serotonin transporter (5-HTT, SLC6A4) gene was suggested to exert a modulating effect on the association between early life stress and the risk for depression. In the present study, we used a 5-Htt6PS paradigm to investigate whether the effects of PS are dependent on the 5-Htt genotype. For this purpose, the effects of PS on cognition, anxiety- and depression-related behavior were examined using a maternal restraint stress paradigm of PS in C57BL6 wild-type (WT) and heterozygous 5-Htt deficient (5-Htt +/2) mice. Additionally, in female offspring, a genome-wide hippocampal gene expression profiling was performed using the Affymetrix GeneChipH Mouse Genome 430 2.0 Array. 5-Htt +/2 offspring showed enhanced memory performance and signs of reduced anxiety as compared to WT offspring. In contrast, ...
Abstract:Adult stem cells are present in many tissues including, skin, muscle, adipose, bone marrow, and in the brain. Neuroinflammation has been shown to be a potent negative regulator of stem cell and progenitor cell proliferation in the neurogenic regions of the brain. Recently we demonstrated that decreasing a key neuroinflammatory cytokine IL-1β in the hippocampus of aged rats reversed the age-related cognitive decline and increased neurogenesis in the age rats. We also have found that nutraceuticals have the potential to reduce neuroinflammation, and decrease oxidative stress. The objectives of this study were to determine if spirulina could protect the proliferative potential of hippocampal neural progenitor cells from an acute systemic inflammatory insult of lipopolysaccharide (LPS). To this end, young rats were fed for 30 days a control diet or a diet supplemented with 0.1% spirulina. On day 28 the rats were given a single i.p. injection of LPS (1 mg/kg). The following day the rats ...
The hippocampus has been the focus of more imaging research than any other subcortical structure in the human brain. However a feature that has been almost universally overlooked are the bumpy ridges on the inferior aspect of the hippocampus, which we refer to as hippocampal dentation. These bumps arise from folds in the CA1 layer of Ammons horn. Similar to the folding of the cerebral cortex, hippocampal dentation allows for greater surface area in a confined space. However, while quantitative studies of radiologic brain images have been advancing for decades, examining numerous approaches to hippocampal segmentation and morphology analysis, virtually all published 3D renderings of the hippocampus show the under surface to be quite smooth or mildly irregular; we have rarely seen the characteristic bumpy structure in the reconstructed 3D scene, one exception being the 9.4T postmortem study. This is presumably due to the fact that, based on our experience with high resolution images, there is a ...
Supplementary MaterialsSupplementary Desk 1: Hypo- and hypermethylated promoter DMRs from adult hippocampus subsequent prenatal ethanol publicity compared to neglected handles filtered by significance ( 0. maternal parting to demonstrate the fact that combination of both remedies results in a lot more than additive deficits. Furthermore, the behavioral deficits are connected with adjustments in hippocampal gene appearance that persist into adulthood. What initiates and keeps these adjustments continues Cidofovir biological activity to be to become set up and forms the concentrate of the record. Specifically, Cidofovir biological activity MeDIP-Seq was used to assess if changes in promoter DNA methylation are affected by exposure to prenatal ethanol and maternal separation including its relationship to gene expression. The novel results show that different sets of genes implicated by promoter DNA methylation are influenced by both remedies independently, and a comparatively unique group of genes ...
Synopsis: Except in trauma, where neural stem cells migrate to replace damaged tissue, neurogenesis in adult humans only occurs in the hippocampus, and possibly the SVN. In rodent models of anxiety/depression (e.g. anxious strains exposed to prolonged periods of stress, including social subordination) hippocampal neurogenesis is inhibited and hippocampal size is reduced, probably through direct action of glucocorticoids on hippocampal neurons and reduced transcription of BDNF and related genes. This may leave the hippocampus less able to excert its normally inhibitory effect on the HPA axis, glucocorticoid levels rise further, and depression ensues. Inhibitors of the serotonin transporter (SSRIs) help the brain break out of this cycle by stimulating hippocampal neurogenesis and BDNF transcription, probably via the 5HT1A receptor (5HT1A knockouts have normal baseline neurogenesis but do not respond to SSRIs). Noradrenaline has comparable effects to serotonin on neurogenesis ...
The activation of the N-methyl-D-aspartate receptor (NMDAR) is critical for the induction of synaptic plasticity in the hippocampus. Aging can alter glutamatergic synaptic transmission in the hippocampus, and cognitive impairments in aged animals are accompanied by reduced NMDARmediated plasticity at Schaffer collateral-CA1 synapses. However, the specific contribution of NMDAR subunits to NMDAR-mediated synaptic responses in aged tissue has not yet been fully understood. The main purpose of present study was to examine whether there is an impact of aging on NMDAR subunit expression and whether synaptic plasticity may depend on NMDAR subunit composition in the aged hippocampus ...
The evidence that adult brains could grow new neurons was a game-changer, and has spawned all manner of products to try and stimulate such neurogenesis, to help fight back against age-related cognitive decline and even dementia. An important study in the evidence for the role of experience and training in growing new neurons was Maguires celebrated study of London taxi drivers, back in 2000.. The small study, involving 16 male, right-handed taxi drivers with an average experience of 14.3 years (range 1.5 to 42 years), found that the taxi drivers had significantly more grey matter (neurons) in the posterior hippocampus than matched controls, while the controls showed relatively more grey matter in the anterior hippocampus. Overall, these balanced out, so that the volume of the hippocampus as a whole wasnt different for the two groups. The volume in the right posterior hippocampus correlated with the amount of experience the driver had (the correlation remained after age was accounted ...
TY - JOUR. T1 - The influence of age on the treadmill exercise-induced c-Fos expression in the hippocampus of rats. AU - Kim, Sang Ho. AU - Kim, Hong. AU - Kim, Sung Soo. AU - Shin, Mal Soon. AU - Chang, Hyun Kyung. AU - Lee, Taeck Hyun. AU - Jang, Mi Hyeon. AU - Shin, Min Chul. AU - Lee, Hee Hyuk. AU - Kim, Young Pyo. AU - Kim, Chang Ju. PY - 2004/7/1. Y1 - 2004/7/1. N2 - c-Fos has been used as a neuronal activity marker. Here, we examined the influence of age on the treadmill running-induced c-Fos expression in rat hippocampus. Rats of exercise groups were forced to run on treadmill for 30 min once a day for 5 consecutive days. Without exercise, c-Fos expression was highest in 8-week old rats. Treadmill exercise significantly enhanced the c-Fos expression in the hippocampus of rats in all ages. In the CA region, the increase of the c-Fos expression by treadmill exercise was highest in 4-week old rats. In the dentate gyrus, the increase of the c-Fos expression by treadmill exercise was highest ...
The hippocampus is one of a group of remarkable structures embedded within the brains medial temporal lobe. Long known to be important for memory, it has been a prime focus of neuroscience research for many years. The Hippocampus Book promises to facilitate developments in the field in a major way by bringing together, for the first time, contributions by leading international scientists knowledgeable about hippocampal anatomy, physiology, and function. This authoritative volume offers the most comprehensive, up-to-date account of what the hippocampus does, how it does it, and what happens when things go wrong. At the same time, it illustrates how research focusing on this single brain structure has revealed principles of wider generality for the whole brain in relation to anatomical connectivity, synaptic plasticity, cognition and behavior, and computational algorithms. Well-organized in its presentation of both theory and experimental data, this peerless work vividly illustrates the ...
Images: Effect of α2δ ligands on neuronal differentiation and proliferation of hippocampus-derived neural progenitor cells. (A) Representative fluorescence microscopy image of a hippocampal neurosphere immunolabelled for nestin (green) and SRY-related HMG-box gene 2 (Sox-2) (red), markers of undifferentiated NPC. Magnification = X600. Scale bar = 56 μm. (B) After 24 h in absence of growth factors, hippocampal Neural Progenitor Cells (NPC) differentiated giving rise to four different cell populations identified by double Microtubule Associated Protein-2 (MAP-2) and nestin immunolabelling: MAP-2+/nestin- mature neurons, MAP-2+/nestin+, MAP-2-/nestin+ and MAP-2-/nestin- cells. Data are expressed as mean ± S.D. of n=9 experiments, run in triplicates. Gabapentin (GBP) and pregabalin (PGB) promote neuronal differentiation of adult hippocampal NPC. GBP (C-F) and PGB (G-J) significantly increased, in a concentrationdependent manner, the percentage of MAP-2+/nestin- (C, G) and MAP-2+/nestin+ (D, H) ...
Poster (2017, November 24). Introduction. Decreased hippocampal volume in older adults is associated with episodic memory decline and subsequent neurodegenerative diseases. According to the dynamic polygon hypothesis, strategies ... [more ▼]. Introduction. Decreased hippocampal volume in older adults is associated with episodic memory decline and subsequent neurodegenerative diseases. According to the dynamic polygon hypothesis, strategies that increase neurogenesis of the hippocampus are likely to be successsful in delaying the onset of cognitive impairment in ageing. Several modifiable factors can have a positive effect on the size of the hippocampus, one of them being cognitive reserve. However, to date, very few studies reported an impact of cognitive reserve on hippocampal volume in healthy older adults. Therefore, the main objective of our study was to explore whether cognitive reserve is linked to hippocampal volume in healthy aging. We focussed particularly on intellectual and social ...
The oscillatory activity of hippocampal neuronal networks is believed to play a role in memory acquisition and consolidation. Particular focus has been given to characterising theta (4-12 Hz), gamma (40-100 Hz) and ripple (150-250 Hz) oscillations. Beyond these well-described network states, few studies have investigated hippocampal beta2 (23-30 Hz) activity in vivo and its link to behaviour. A previous sudy showed that the exploration of novel environments may lead to the appearance of beta2 oscillations in the mouse hippocampus. In the present study we characterised hippocampal beta2 oscillations in mice during an object recognition task. We found prominent bursts of beta2 oscillations in the beginning of novel exploration sessions (four new objects), which could be readily observed by spectral analysis and visual inspection of local field potentials. Beta2 modulated hippocampal but not neocortical neurons and its power decreased along the session. We also found increased beta2 power in the ...