Neurochemical assays revealed that the H1R-KO mice had significantly lower levels of AChE activity in the dentate gyrus (DG) and CA1 subregions of the hippocampus as compared with the WT mice. 
In one case with UDG, TDP-43-ir NCIs were also detected in the substantia nigra, and some regions of the cerebrum, including the hippocampal dentate gyrus (granule cells). The number of neurons displaying NCIs in each region was very small (1-3 per region, except the dentate gyrus).
These changes in mitochondrial metabolism coincided with an increase in mitochondrial number and dendritic spine synapses in granule cells of the dentate gyrus and the stratum radiatum of the CA1 region and were dependent on UCP2 expression, because in UCP2 knock-out mice such changes were not observed.
To address these issues, we recorded dual component (AMPA and NMDA) miniature excitatory postsynaptic currents (mEPSCs) from cortical and hippocampal pyramidal neurons and dentate gyrus granule cells from acute brain slices.
Recently we reported that astroglial loss and subsequent gliogenesis in the dentate gyrus play a role in epileptogenesis following pilocarpine-induced status epilepticus (SE). Unlike the dentate gyrus and the entorhinal cortex, CA1 astroglial damage was protected by conventional anti-epileptic drugs. Astroglial regeneration in the dentate gyrus and the stratum oriens of the CA1 region was found to originate from gliogenesis, while that in the entorhinal cortex and stratum radiatum of the CA1 region originated from in situ proliferation.
We found profound pathological changes in the hippocampus and large numbers of HSV-1 antigen-positive cells in the dentate gyrus (DG) subfield of HSV-1-infected rats.
We examined whether folate deficiency affects platelet endothelial cell adhesion molecule-1 (PECAM-1), which is an immunoglobulin-associated cell adhesion molecule and mediates the final common pathway of neutrophil transendothelial migration, in blood vessels in the gerbil dentate gyrus after transient forebrain ischemia. In the control diet (CD)- and FAD-treated sham-operated groups, weak PECAM-1 immunoreactivity was detected in the blood vessels located in the dentate gyrus. Western blot analyses showed that the change patterns in PECAM-1 protein levels in the dentate gyrus in both groups after ischemic insult were similar to changes in PECAM-1 immunohistochemistry in the ischemic dentate gyrus. Our results suggest that folate deficiency enhances PECAM-1 in the dentate gyrus induced by transient ischemia..
Research over the last few decades has firmly established that new neurons are generated in selected areas of the adult mammalian brain, particularly the dentate gyrus of the hippocampal formation and the subventricular zone of the lateral ventricles.
Here we report findings on the topographical organization of the major connections of the dentate gyrus. Localized anterograde tracer injections were made at various rostrocaudal levels of the dentate gyrus, and we investigated the three-dimensional organization of the mossy fibers, the associational projection, and the local projections. The associational projection, though modest at the level of origin, travels both rostrally and caudally from the injection site for as much as 80% of the rostrocaudal extent of the dentate gyrus. Overall, the topographic organization of the intrinsic connections of the monkey dentate gyrus is largely similar to that of the rat. Such extensive longitudinal connections have the potential for integrating information across much of the rostrocaudal extent of the dentate gyrus.
Newborn cells of the adult dentate gyrus in the hippocampus are characterized by their abundant expression of polysialic acid (PSA), a carbohydrate attached to the neural cell adhesion molecule (NCAM). PSA+ newborn cells of the dentate gyrus form clusters with proliferating neural progenitor cells, migrate away from these clusters, and terminally differentiate. To identify the roles of PSA in the development of adult progenitors of the dentate gyrus, we injected endoneuraminidase N (endoN) into the hippocampus of adult rats to specifically cleave PSA from NCAM.
In the dentate gyrus (DG), however, neuronal loss and mossy fiber sprouting are associated with enhanced inhibition rather than progressive hyperexcitability.
Adult neurogenesis in the dentate gyrus plays a critical role in hippocampus-dependent spatial learning. To investigate these issues, we used a mouse model in which the differentiation of adult-generated dentate gyrus neurons can be anticipated by conditionally expressing the pro-differentiative gene PC3 (Tis21/BTG2) in nestin-positive progenitor cells. New, adult-generated dentate gyrus progenitors, in which the PC3 transgene was expressed, showed accelerated differentiation and significantly reduced dendritic arborization and spine density. Functionally, this genetic manipulation specifically affected different hippocampus-dependent learning and memory tasks, including contextual fear conditioning, and selectively reduced synaptic plasticity in the dentate gyrus.
In this study, we observed glial fibrillary acidic protein (GFAP), a marker for astrocytes, immunoreactivity in the dentate gyrus and hippocampus proper (CA1-3 region) of adult (2-3 years of age) and aged (10-12 years of age) dogs. In the adult group, GFAP immunoreactive astrocytes were distributed in all layers of the dentate gyrus and CA1-3 region, except in the stratum pyramidale of the CA1-3 region. In the aged group, GFAP immunoreactivity decreased markedly in the molecular layer of the dentate gyrus. GFAP protein levels in the aged dentate gyrus decreased; however, GFAP levels in the CA1-3 region increased. These results suggest that the morphology of astrocytes and GFAP protein levels in the hippocampal dentate gyrus and CA1 region are changed, respectively, with age..
The main subfields of the hippocampus (cornu ammonis fields CA1, CA2/3; the dentate gyrus; and the vestigial hippocampal sulcus) are labeled in the images manually using a combination of distinguishable image features and geometrical features.
After the confirmation of the anti-epileptic effect, MFS in dentate gyrus (DG) supragranular layer was investigated by timm's staining.
For histological assessment, the ratio of the surviving neurons (ipsilateral/contralateral) was calculated in the cornu ammonis fields, CA1 and CA3, and the dentate gyrus (DG).
The age at IPI was found to be related to MTS variants (p<0.01) and significantly correlated to cell loss in the CA1 sector and the dentate gyrus (p < 0.05).
Application of both, abn-CBD or 2-AG to lesioned OHSC significantly decreased the number of IB(4) (+) microglial cells and PI(+) neurons in the dentate gyrus.
We have previously found that synaptic pathway from the basolateral amygdala (BLA) to the dentate gyrus (DG) displays N-methyl-d-aspartate (NMDA) receptor-independent form of long-term potentiation (LTP), which should be a valuable model for elucidating neural mechanisms linking emotion and memory.
Aluminum exposure impaired learning and memory in wild mice and increased the total number of proliferating cells in the dentate gyrus of hippocampus.
Interestingly, GPR54 is also highly expressed in granule cells of the hippocampal dentate gyrus, and in a previous study we showed that kisspeptin enhances excitatory synaptic transmission in these cells.
To address the functional role of synaptotagmin 1 at identified inhibitory terminals, we made paired recordings from synaptically connected basket cells (BCs) and granule cells (GCs) in the dentate gyrus in organotypic slice cultures from wild-type and synaptotagmin 1-deficient mice.
New neurons in the adult dentate gyrus are widely held to incorporate into hippocampal circuitry via a stereotypical sequence of morphological and physiological transitions, yet the molecular control over this process remains unclear.
Hybridization and immunohistochemistry indicated that Brn-4 signals in hippocampus and dentate gyrus (DG) of the deafferented side were significantly stronger than the normal side.
Using unanesthetized 1- to 12-d-old rats, we report here that the majority of neurons in CA1 and the dentate gyrus (DG) are significantly more active during AS than during either quiet sleep or wakefulness.
To study the benefits of the nettle in diabetic encephalopathy, the granule cell density of the dentate gyrus of diabetic rats was studied following administration of Urtica dioica extract. dioica extract can help compensate for granule cell loss in the diabetic rat dentate gyrus, which can ameliorate cognitive impairment in diabetes.
In the hippocampal formation, IGFBP4 immunoreactivity was also decreased in the pyramidal cells of CA1-3 areas and the granule cells of dentate gyrus.
Compared with the control animals, intranasal administration of bFGF improved behavioral recovery without affecting infarct size, and enhanced proliferation of progenitor cells in the subventricular zone and the subgranular zone of the dentate gyrus (DG).
We studied auditory gating and the effects of the cannabinoid agonist WIN55,212-22 on gating in CA3 and dentate gyrus (DG) of the hippocampus and medial prefrontal cortex (mPFC) in male Lister hooded rats using in vivo electrophysiology.
Moreover, depending of the area analysed, the basal binding of [ (35)S]GTPgammaS was differentially affected by this treatment: increased in DRN and decreased in hippocampal dentate gyrus.
Immunohistochemistry demonstrated that the decrease in overall SC1 protein levels was reflected by a reduction of SC1 signal in granule cells of the dentate gyrus.
Rats receiving VNS at the output current of 0.75 mA VNS for 2 days showed a significant 50% increase in dentate gyrus BrdU-incorporation consistent with an increase in progenitor proliferation. Specific analysis for progenitor survival revealed no effects by VNS on dentate gyrus BrdU-labeling. These results suggest that VNS induced an increase in the number of available progenitor cells in the adult rat dentate gyrus by a mechanism presumably involving increased progenitor proliferation..
Here we report that mice heterozygous for a null mutation of the alpha-isoform of calcium/calmodulin-dependent protein kinase II (alpha-CaMKII+/-) have profoundly dysregulated behaviours and impaired neuronal development in the dentate gyrus (DG).
These diseases have been associated with an increased neurogenesis in the adult rodent dentate gyrus. At different time points thereafter dentate gyrus neurogenesis was investigated by means of intraperitoneal bromodeoxyuridine injections and immunocytochemistry. We detected about 280% more newborn cells in the dentate gyrus of rats that received bromodeoxyuridine during the first week after SD and were allowed to recover for 6 weeks. CONCLUSIONS: From our data we postulate that the increased dentate gyrus neurogenesis observed after brain injury may at least partly be mediated by SD-like epiphenomena. Furthermore they indicate that even a strongly enhanced dentate gyrus neurogenesis may occur without significant improvements in hippocampus-dependent spatial learning and memory..
While the C18-species was widely distributed throughout the frontal brain, the C20-species selectively localized along the entorhinal-hippocampus projections, especially in the molecular layer (ML) of the dentate gyrus (DG).
The SC pathway transmits information to area CA1 that originates in entorhinal cortex and is processed by the dentate gyrus and area CA3.
One month after cranial irradiation (6 Gy, X-ray), changes in the population of immature and proliferating neurons in dentate gyrus were localized through the expression of the microtubule binding protein doublecortin (Dcx) and proliferation marker Ki-67.
Acute seizures are classically associated with augmentation of neurogenesis and migration of newly born neurons into ectopic regions such as the hilus and the molecular layer of the dentate gyrus.
Neurogenesis in the adult dentate gyrus but not the subependymal zone is abolished.
The tailless (Tlx) gene encodes an orphan nuclear receptor that is expressed by neural stem/progenitor cells in the adult brain of the subventricular zone (SVZ) and the dentate gyrus (DG).
Immunohistochemical studies found that CD226 is primarily located in the hilus of the dentate gyrus and stratum lucidum aligned along the pyramidal cells in the hippocampal CA3 area, the interspaces of granular cells and the somata of the Purkinje cells in the cerebellar cortex during adulthood.
Adult offspring of time-pregnant dams that were given a deficient level of choline (DEF=0.0 g/kg), sufficient choline (CON=1.1 g/kg) or supplemental choline (SUP=3.5 g/kg) in their chow during embryonic days (ED) 12-17 were implanted with an electroencephalograph (EEG) electrode in the hippocampal dentate gyrus in combination with an electromyograph (EMG) electrode patch implanted in the nuchal muscle.
Most GAD67/alpha2 co-expression was located in CA1/CA3 stratum oriens, and GAD67/alpha5 co-expression was predominantly detected in CA1/CA3 stratum radiatum/lacunosum moleculare and the dentate gyrus.
This study investigated pubertal changes in dendritic complexity of dentate gyrus neurons. We found that the structure of neurons in the lower, but not upper, blade of the dentate gyrus changed during adolescence. These data demonstrate that dentate gyrus neurons undergo substantial structural remodeling during adolescence and that patterns of maturation are region specific.
Importantly, chronic treatment with escitalopram reversed the decrease in cytogenesis in the rat dentate gyrus, induced by chronic mild stress. However, in naïve rats, while chronic treatment with R-citalopram did not modify the basal proliferation rate in the dentate gyrus, it blocked the increase induced by escitalopram when coadministered.
At the postnatal 44-60 days, all the pup rats were given an extracellular recording measured in dentate gyrus (DG) area of hippocampus.
Neurogenesis persists throughout life in the adult mammalian dentate gyrus and is regulated by several environmental, physiological, and molecular factors.
One such region that provides the proper milieu to sustain progenitor cells and is permissive to neuronal fate determination is located in the dentate gyrus of the hippocampus.
Aged SUP males and females had more newly proliferated cells in the hippocampal dentate gyrus and protein levels of vascular endothelial growth factor (VEGF) and neurotrophin-3 (NT-3) were significantly elevated in female SUP rats in comparison to all other groups.
In vivo, Noggin is expressed in the adult dentate gyrus and limits BMP signaling in proliferative cells of the SGZ.
Our previous studies show that application of high-frequency stimulation (HFS) sufficient to elicit LTP at the dentate gyrus (DG)-CA3 pathway produces mossy fiber structural modifications 7 days after tetanic stimulation.
Adult male rats fed a zinc-restricted diet had approximately 50% fewer Ki67-positive stem cells in the subgranular zone (SGZ) and granular cell layer of the dentate gyrus compared to both zinc-adequate and pair-fed controls (p<0.05).
Our recent studies using morphometric techniques have further shown that ethanol neurotoxicity appears to affect the development of the dentate gyrus in a region-specific manner; it was found that early postnatal ethanol exposure causes a transitory deficit in the hilus volume of the dentate gyrus. Based on reports on possible factors deciding ethanol neurotoxicity to the brain, we review developmental neurotoxicity to the dentate gyrus of the hippocampal formation..
Our results show that the human CMV-IE promoter resulted in efficient transgene expression in the entire hippocampus whereas transgene expression mediated by the hybrid hEF1alpha/HTLV promoter was limited mainly in the dentate gyrus and the CA2/3 region. Finally, the neuron-specific human synapsin I promoter was particularly effective in the dentate gyrus.
On the dentate gyrus granule cells (DG), on the other hand, the significant neuronal survival was observed even as low as 1mM.
OBJECTIVE: To investigate the relationship among mossy fiber axon sprouting(MFS), synaptic reorganization, and the alteration of expression of Eph A5 and ephrin A3 in the dentate gyrus in rats with pilocarpine-induced chronic temporal lobe epilepsy. CONCLUSION: The down-regulation of Eph A5 mRNA and protein in entorhinal cortex and dentate gyrus, and ephrin A3 mRNA in dentate gyrus after status epilepticus may be part of the endogenous molecular mechanism of mossy fiber sprouting to the inner molecular layer of dentate gyrus..
In an immunohistochemical study, we found that increased pCaMKIIalpha and pERK expressions were mainly located at CA3 or the dentate gyrus of the hippocampus.
While changes in infants' encoding may be attributed to rapid myelination during the first year of life, improvements in long-term retention and flexible retrieval are likely due to the prolonged development of the dentate gyrus.
Here, we used synaptopodin -/- mice to explore the role of the spine apparatus and the cisternal organelle in synaptic plasticity and local circuit excitability in response to activation of the perforant path input to the dentate gyrus in vivo.
The granule cells of the dentate gyrus form the input stage of the hippocampal trisynaptic circuit and their function is strongly influenced by peptidergic systems. RT-PCR experiments showed that KiSS-1 is expressed in the dentate gyrus.
In both of HD- and LD-fed C57BL/6N and C3H/HeN mice for 4 weeks, some Ki67 and many DCX immunoreactive cells were detected in the subgranular zone of the dentate gyrus.
In this study, the effects of prenatal exposure to EMF on the number of granule cells in the dentate gyrus of 4-week-old rats were investigated. The numbers of granule cells in the dentate gyrus were analyzed using the optical fractionator technique. The results showed that prenatal EMF exposure caused a decrease in the number of granule cells in the dentate gyrus of the rats (P<0.01). This suggests that prenatal exposure to a 900 MHz EMF affects the development of the dentate gyrus granule cells in the rat hippocampus. Cell loss might be caused by an inhibition of granule cell neurogenesis in the dentate gyrus..
RESULTS: Traumatic brain injury caused tissue loss in the cortex and cell loss in the dentate gyrus (DG) as well as impairment of sensorimotor function (footfault testing) and spatial learning (Morris water maze).
Here, using a genetic labeling method in adult mice, we found that continuous neurogenesis results in the replacement of the majority of granule neurons in the olfactory bulb and a substantial addition of granule neurons to the hippocampal dentate gyrus. Genetic ablation of newly formed neurons in adult mice led to a gradual decrease in the number of granule cells in the olfactory bulb, inhibition of increases in the granule cell number in the dentate gyrus and impairment of behaviors in contextual and spatial memory, which are known to depend on hippocampus. These results suggest that continuous neurogenesis is required for the maintenance and reorganization of the whole interneuron system in the olfactory bulb, the modulation and refinement of the existing neuronal circuits in the dentate gyrus and the normal behaviors involved in hippocampal-dependent memory..
Intraperitoneal administration induced Fos-IR in some additional regions including the nucleus accumbens and dentate gyrus.
These slices permitted recordings from the dentate gyrus, the CA3 and CA1 regions and the subiculum of both the injected and the contralateral non-injected hippocampus.
Here, we have investigated the overall expression of AMPA- and NMDA-type glutamate receptors (AMPARs and NMDARs, respectively), as well as their levels at the synaptic surface membrane and in the postsynaptic density (PSD), in the dentate gyrus at 48h following the induction of LTP at perforant path synapses in awake rats. We found a high-frequency stimulation-dependent increase in the overall levels of AMPAR subunits GluA1 and GluA2, but not GluA3 in the dentate gyrus.
The immunostaining in MP4 showed a decrease in the granulare layer from dentate gyrus (20%), in hillus (71%) and subicullum (63%) as compared with control and these decreases were similar at MP7 values.
Preexposure to LPS immediately before OGD increased propidium iodide-determined cell death in regions CA1, CA3, and dentate gyrus from 4 up to 48 h after OGD (P<0.001).
We found that Kv4.2, Kv4.3 and KChIP2 staining in the molecular layer of the dentate gyrus changes from being uniformly distributed across the molecular layer to concentrated in just the outer two-thirds.
increased amplitude of population spike (PS) recorded in the dentate gyrus and reduced paired-pulse inhibition in the CA1 area.
The role of these receptors in spatial learning, and in synaptic plasticity in the dentate gyrus in vivo has not yet been the subject of close scrutiny. We investigated the effects of group II mGluR antagonism on LTP and LTD in the adult rat, at medial perforant path-dentate gyrus synapses, and on spatial learning in the eight-arm radial maze. Acute injection of EGLU did not affect either LTD or LTP in the dentate gyrus in vivo.
Furthermore, familiarity with the environmental cues/context was found to significantly enhance Fos expressions in dorsal striatum and dentate gyrus.
Both forms of exercise increased the number of surviving bromodeoxyuridine (BrdU)+ cells in the dentate gyrus after 8 weeks of exercise, although forced exercisers had significantly more than voluntary exercisers.
Ultrastructural analysis revealed that PR labeling is present in extranuclear profiles throughout the CA1 and CA3 regions and dentate gyrus, and, in contrast to light microscopic findings, in nuclei of a few pyramidal and subgranular zone cells.
However, new mutant neurons failed to fully mature as indicated by their lack of calbindin, reduced dendritic differentiation and an accumulation of calretinin(+) immature neurons in the BDNF mutant dentate gyrus.
Here we show that mice lacking the p75 neurotrophin receptor (p75(NTR-/-)) have 25% fewer neuroblasts and 50% fewer newborn neurons in the dentate gyrus, coincident with increased rates of cell death of newly born cells and a significantly smaller granular cell layer and dentate gyrus, than those of p75(NTR+/+) mice.
Two regions of the mammalian brain maintain the capability to generate new neurons throughout lifetime: Neuronal stem- and precursor cells proliferate in the subgranulare zone (SGZ) of the dentate gyrus in the hippocampus and in the subventricular zone (SVZ) of the lateral ventricles to give rise to new neurons that are functionally integrated into the neural network.
Neurogenesis in the dentate gyrus (DG) contributes to forming spatial memory in the ischemic brain.
However, TASK-1 immunoreactivity in GFAP(+) astrocytes is markedly decreased in the dentate gyrus.
Neurogenesis persists in certain regions of the adult brain including the subgranular zone of the hippocampal dentate gyrus wherein its regulation is essential, particularly in relation to learning, stress and modulation of mood.
Six weeks post-phencyclidine, analysis of brains showed a reduction in expression of parvalbumin immunoreactive neurons in the hippocampus with significant reductions localised to the CA1 and dentate gyrus regions.
In the dentate gyrus, however, VEGFR-3 expression was transiently increased in the innermost layer of granule cells on days 7-10 after reperfusion, coinciding with an increase in polysialylated neural cell adhesion molecule staining--a marker for immature neurons.
This inhibition occurs in the caudal areas of the dentate gyrus (DG) of the hippocampus, a neurogenic area mainly involved in learning and memory performance, and in the SVZ, recently implicated in olfactory learning performance.
Pneumococcal meningitis is associated with caspase 3-dependent apoptosis of recently post-mitotic immature neurons in the dentate gyrus of the hippocampus. At the cellular level, JNK3 activation was accompanied in the dentate gyrus by markedly increased phosphorylation of its major downstream target c-Jun in early immature (Hu-positive) neurons, but not in migrating (doublecortin-positive) neurons, the cells that do undergo apoptosis.
Correlational analyses revealed that in male rats, fearful behavior was positively correlated with synapsin I immunoreactivity in hippocampal brain regions located ipsilateral to the site of stimulation (i.e., the CA1 and CA3 subfields of the hippocampus, the dentate gyrus and the hilus) and negatively correlated with synapsin I immunoreactivity bilaterally in the basolateral and central amygdala.
Proliferating cells within the adult dentate gyrus of the hippocampus give rise to new neurons involved in memory and learning and require neurotrophic factors such as brain-derived neurotrophic factor (BDNF) to nurture this process of adult neurogenesis. We propose that systemically administered 5-Fu chemotherapy will cause deficits in hippocampal memory that are associated with altered BDNF levels and proliferating cells (particularly vascular-associated cells) in the dentate gyrus. Numbers of vascular-associated (VA) and non-vascular-associated (NVA) proliferating cells in the dentate gyrus were measured using double-labelling immunohistochemistry with markers of proliferation (Ki67) and endothelial cells (RECA-1). 5-Fu chemotherapy caused a marginal disruption in spatial working memory and did not alter the total proliferating cell counts or the percentage of VA and NVA proliferating cells in the dentate gyrus.
In vivo, induction of a status epilepticus by systemic administration of the chemoconvulsant kainic acid resulted in markedly reduced neurodegeneration in the pyramidal layer of the hippocampus, dentate gyrus and hilus of MK2-deficient mice compared with wild-type mice.
However, TASK-1 immunoreactivity in GFAP(+) astrocytes is markedly decreased in the dentate gyrus.
During the early developmental stage, a neural circuit is established between the entorhinal cortex (EC) and the hippocampal dentate gyrus (DG) via the perforant pathway.
Neural progenitor cells (NPCs) in the dentate gyrus (DG) that are capable of continuous proliferation and neuronal differentiation are the source of such structural plasticity.
It has become generally accepted that new neurones are added and integrated mainly in two areas of the mammalian CNS, the subventricular zone and the subgranular zone (SGZ) of the dentate gyrus (DG) of the hippocampus, which is of central importance in learning and memory.
By using comparative real-time PCR, Taqman gene expression assays, and the delta-delta comparative threshold method we detected a significant reduction in Kcnma1 expression in microdissected dentate gyrus at different intervals after status epilepticus (24 h, 10 days, 1 month, and more than 2 months).
Finally, direct injection of rSV40 vectors into rat femoral bone marrow (BM) led to transgene expression in CNS neurons and microglia, mostly in the dentate gyrus and in the periventricular subependymal zone, suggesting that BM-derived cells may be progenitors of some CNS cells in adult animals, and that gene delivery to BM may allow transgene expression in newly formed neurons..
Within the HF, leu-enkephalin (LENK) is most prominent in the mossy fiber (MF) pathway formed by the axons of dentate gyrus (DG) granule cells.
in the perforant path to dentate gyrus, from the dentate gyrus to CA3 area, from CA3 to CA1 area and from CA1 to the subiculum) but potentiation of the efficacy of the perforant input to pyramids of CA1 and CA3 areas and increase in efficacy of associative connections between CA3 neurones.
The opposite relation was observed for the Cu level in the dentate gyrus and for Zn in the CA3 region of the hippocampus and in the dentate gyrus..
To address this question, we investigated the effect of ECS on proliferation of neural stem-like and/or progenitor cells in the subgranular zone of rat dentate gyrus.
In this study, we investigated whether the expression of pyridoxal kinase (PLK) and pyridoxine-5'-phosphate oxidase (PNPO) are altered following long-term potentiation (LTP) induction, and whether Tat-PLK and Tat-PNPO transductions affect LTP induction and paired-pulse responses in the rat dentate gyrus (DG).
Compared with the swimming only group and holding-box group, agmatine levels were significantly increased in the CA1 and dentate gyrus subregions of the hippocampus, the entorhinal cortex and the vestibular nucleus in the water-maze training group.
In contrast, it was found mainly in the hippocampal dentate gyrus and pyramidal cell layer that contains mainly glutamatergic neurons. In the dentate gyrus, NELL2 was not detected in the GFAP-positive neural precursor cells, but was generally present in mature neurons of the subgranular zone, suggesting a role in this region restricted to mature neurons..
These markers were detected in the subgranular zone of the dentate gyrus in vehicle- and EPG-treated groups.
Anatomical assessment at approximately 7 1/2 months of age was conducted by using design-based stereology to quantify the total cell number in five hippocampal subregions [ granule layer (GL), hilus of the dentate gyrus (DGH), cornu ammonis fields (CA)2/3, CA1, and subiculum (SUB)] [ Fitting, S., Booze, R.M., Hasselrot, U., Mactutus, C.F., 2007a.
One day after SE, TASK-1 immunoreactivity in astrocytes was markedly reduced only in the molecular layer of the dentate gyrus. One week after SE, loss of astrocytes was observed in the molecular layer of the dentate gyrus. Four weeks after SE (when spontaneous seizure developed), typical reactive astrogliosis was observed in the dentate gyrus and the CA1 region.
dentate gyrus neurogenesis was also affected by the disease: proliferation and differentiation measured by bromodeoxyuridine immunodetection were significantly reduced in both experimental models used.
Moderate levels were observed in some amygdaloid nuclei, CA2 area and dentate gyrus of hippocampus, endopiriform nuclei, globus pallidus, striatum, molecular layer of cerebellum, and locus coeruleus, whereas no expression was detected in hypothalamic nuclei, CA1 and CA3 areas of hippocampus, zona incerta.
In the adult mammalian brain, neurogenesis from neural stem/progenitor cells continues in two regions: the subgranular zone in the dentate gyrus and the subventricular zone lining the lateral ventricles.
As compared to the wild-type injured mice, EPOR-null mice did not exhibit higher susceptibility to TBI as exemplified by tissue loss in the cortex, cell loss in the dentate gyrus, impaired spatial learning, angiogenesis and cell proliferation.
In d12 pigs, 5-HT(1A) receptor mRNA expression per unit area was 29%, 63%, 52% and 64% lower than in d42 pigs in the parvocellular PVN, amygdala and hippocampal dentate gyrus and pyramidal cell layer, respectively.
This approach allowed us to investigate the effects of spatially restricted overexpression of MR and a negative transdominant GR (TD) in the dentate gyrus (DG) subfield of the hippocampus, on short term and long term spatial memory in animals overexpressing one copy of MR or TD, two copies of MR ("MR/MR"), or one copy of each ("MR/TD").
It has been suggested that the dentate gyrus (DG) and CA3 cooperate to efficiently process spatial information.
By analyzing the spatial distribution of NG2(+) cells in the hilus of the mouse dentate gyrus, we demonstrate that NG2(+) cells are indeed closely associated to interneurons.
We examined the differences in Ki-67 (a proliferating cell marker) and doublecortin (DCX; an immature progenitor cell marker) immunolabelling in the dentate gyrus (DG) of the adult hippocampus in three strains of mice (ICR, C57BL/6, and BALB/c) to evaluate the effect of genetic background on adult hippocampal neurogenesis.
The hippocampus receives information from the cortex; relays it through the dentate gyrus (DG), Cornu Ammonis (CA) 3, and then CA1; and sends it back to the cortex.
Moreover, we have noted the existence of longitudinal fiber systems in the dentate gyrus. In the dentate gyrus, we found 2 types of longitudinal fiber systems originating from the hilar cells in the dentate gyrus-Type I and Type II fiber systems-by using the anterograde labeling technique with Phaseolus vulgaris-leucoagglutinin (PHA-L) and the retrograde labeling method with fluorescent dyes or the cholera toxin-B subunit. The Type I fiber system extended over almost the entire longitudinal (septotemporal) extent of the dentate gyrus, but in case of injection of the labeling molecule at the extreme temporal level, it extended within the temporal half of the dentate gyrus. In contrast, the cells of origin of the Type II fiber system seemed to extend their dendrites over the outer molecular layer of the dentate gyrus. It appears likely that these longitudinal fiber systems of the dentate gyrus and the field CA3 function as an important system for analyzing information under physiological conditions, but under pathological conditions such as epileptic seizure abnormal neuronal bursting might expand to the entire extent of the hippocampus via these longitudinal systems..
The hippocampus is believed to play a role in processing information relative to the context in which emotionally salient experiences occur but evidence on the specific contribution of the hippocampal dentate gyrus (DG) to these processes is limited.
More specifically, PCP-treated animals displayed decreased AMPA receptor density in hippocampus CA1 (-16%), hippocampus CA2 (-25%), dentate gyrus (-27%), parietal cortex layers III-VI (-19%), central nucleus of the amygdala (-40%), and basolateral amygdala (-19%).
In addition, immunohistochemistry was used to investigate cell proliferation and differentiation in the dentate gyrus of the hippocampus. nucifera rhizome (MNR) resulted in significant improvements of memory functions and neurogenesis in the dentate gyrus. Immunohistochemical analyses using BrdU, Ki-67, and DCX showed significantly increased cell proliferation and cell differentiation in the dentate gyrus.
RABV infection of mice caused a strong induction of calcitonin gene-related peptide (CGRP) in neurons and fibres in the neocortex as well as in the dentate gyrus and CA1 region of the hippocampus although RABV did not infect neurons in which CGRP expression was upregulated.
Three-dimensional analysis of 21 507 dendritic spines in the dentate gyrus, a region crucial for learning and memory, revealed a substantial decrease in the frequency of large spines in plaque-free regions of APP/PS1 mice.
Activation of dentate gyrus granule neurons increased Arc expression 3.5-fold in wildtype mice but only 2.3-fold in Arg-61 mice.
Radiation-induced changes in the population of immature and proliferating neurons in the dentate gyrus were localized using anti-doublecortin (Dcx) and anti-Ki-67 expression.
In this study we investigated the influence of ketogenic diet on adult neurogenesis in the dentate gyrus. In both female and male rats, the amounts of bromodeoxyuridine immunoreactive cells in the dentate gyrus were the same in the different groups. Our results suggest that the ketogenic diet does not disturb the neurogenesis in the rat dentate gyrus..
Ample evidence points to the dentate gyrus as anatomical region for persistent neurogenesis in the adult mammalian brain.
Children have more ongoing cell birth in the dentate gyrus than adults, and markers of cell division are further increased in children with refractory temporal lobe epilepsy. There are clear age-dependent differences in how seizures alter cell birth in the dentate gyrus both acutely and chronically. Future studies need to focus on how these changes in neurogenesis influence dentate gyrus function and what they imply for epileptogenesis and learning and memory impairments, so commonly found in children with temporal lobe epilepsy..
Over the last decade, abnormal neurogenesis in the dentate gyrus (DG) has emerged as another hallmark of TLE.
Endogenous neural progenitor cells (NPCs) located in the adult rodent dentate gyrus and striatal subventricular zone are stimulated by experimental status epilepticus (SE) to generate increased numbers of dentate granule cells (DGCs) and olfactory interneurons, respectively (Bengzon et al., 1997; Parent et al., 1997, 2002; Scott et al., 1998).
Status epilepticus (SE) not only results in an increased number of newly generated neurons in the dentate gyrus but also leads to structural alterations of many of these newborn granule cells. This article will describe these structural alterations of granule cells found in the dentate gyrus after SE and will also discuss the time course of these events and possible underlying causes..
Adult generated neurons in the dentate gyrus become functionally integrated into the existing hippocampal circuit by forming synapses with mature neurons.
Freely-moving Tc1 mice exhibit reduced LTP 1 h after induction but normal maintenance over days in the dentate gyrus of the hippocampal formation.
By combining retroviral expression of green fluorescent protein in adult-born neurons of the mouse dentate gyrus with immuno-electron microscopy, we found output synapses that were formed by labeled terminals on appropriate target cells in the CA3 area and the hilus.
In the hippocampus, the putrescine levels were significantly decreased in the CA1 and dentate gyrus, and increased in the CA2/3 with age.
We report that Disc1 is expressed throughout the hippocampus during embryonic development, with expression becoming increasingly specialized in Ammon's horn and dentate gyrus granule cells within the first postnatal week.
This study was, therefore, designed to examine the effects of lipopolysaccharide (LPS), a bacterial endotoxin known to cause the neuroinflammation, on the neurogenesis in the dentate gyrus of adult mice using the bromodeoxyuridine (BrdU) -pulse chase method. LPS failed to affect the number of BrdU-labeled cells in the dentate gyrus 2 h after BrdU injection, indicating no effects of LPS on the proliferation of the neural stem cells (NSCs). We also observed that LPS increased cell death in the dentate gyrus using terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) staining, suggesting that LPS impaired the survival of newborn cells derived from the NSCs. Furthermore, the central injection of NS398 also ameliorated LPS-induced suppression of the newborn cell survival in the dentate gyrus. The treatment with LPS increased the expression of COX-2 protein 7 h and 7 days after the injection in the dentate gyrus. These results suggest that LPS impairs the survival of newly generated cells derived from the NSCs in the dentate gyrus without affecting the differentiation fate, and these effects of LPS were mediated presumably by COX-2 expression in the dentate gyrus..
Proliferation in the dentate gyrus was measured by assaying expression of the endogenous proliferative marker, Ki67.
Then, osmotic pumps and cannulae were implanted to infuse calcineurin inhibitors (FK506 or cyclosporin A) or an L-type calcium channel blocker (nicardipine) into the dorsal dentate gyrus.
Unlike CXCR4, CXCR7 was abundant in neurons forming the cortical plate and sparse in the developing dentate gyrus and cerebellar external germinal layer. In the adult brain, CXCR7 was expressed by blood vessels, pyramidal cells in CA3, and mature dentate gyrus granule cells, which is reminiscent of the SDF-1 pattern.
Although each of these three Hsps had a distinct regional distribution within the hippocampus, a low level of all of them was observed in the granule cell layer of the dentate gyrus in naïve animals.
A different pattern of behavioral and biochemical changes was present after pre-test administration of alpha-helical CRF((9-41)) (10mug/rat): a decrease in rat fear response and serum corticosterone concentration; an attenuation of fear-induced c-Fos expression in the dentate gyrus, CA1, Cg1, Cg2, and M1 areas of the frontal cortex; a complete reversal of the rise in the number of CRF immunoreactive complexes in the M2 cortical area, induced by conditioned fear.
High-frequency stimulation (HFS) of the medial perforant path to induce LTP was studied in the dentate gyrus with or without the selective CB(1) receptor antagonist, SR141716A in isoflurane-anaesthetised rats. These results indicate that LTP in the dentate gyrus reduces local circuit inhibition, consistent with a reduction of GABA release and/or duration of the post-synaptic GABA-receptor mediated response.
This shift in E(GABA) altered synaptic integration, increased granule cell excitability, and resulted in compromised "gate" function of the dentate gyrus. Furthermore, post-STEP and furosemide effects interacted occlusively, both on E(GABA) in granule cells, and on gatekeeper function of the dentate gyrus.
After a longer period of SE, the lesion invariably involves the upper blade of the dentate gyrus. Adult rats treated with subcutaneous diazepam (20 mg kg for 3 days) did not develop the dentate gyrus lesion and had less frequent spontaneous recurrent seizures (p < 0.01).
In the present study, late-adult (19-month-old) rats were fed for 8 weeks with two medium chain triglycerides (MCT)-KDs, and the following morphologic parameters reflecting synaptic plasticity were evaluated in stratum moleculare of hippocampal CA1 region (SM CA1) and outer molecular layer of hippocampal dentate gyrus (OML DG): average area (S), numeric density (Nv(s)), and surface density (Sv) of synapses, and average volume (V), numeric density (Nv(m)), and volume density (Vv) of synaptic mitochondria.
To elucidate the mode of action of RA-induced antidepressant-like activity, proliferative effect of RA on newborn cells in the dentate gyrus of mouse hippocampus was investigated using immunohistochemical analysis with bromodeoxyuridine (BrdU), a marker of proliferating cells. These results suggest that RA produces an antidepressant-like effect at least in part via the proliferation of newborn cells in the dentate gyrus of the hippocampus..
Training on some associative learning tasks increases the likelihood that new cells in the subgranular zone of the dentate gyrus will survive.
To identify new phosphoproteins associated with LTP, we have undertaken a proteomic study of phosphoproteins at different time points following the induction of LTP in the dentate gyrus in vivo (0, 15 and 90 min). For each time point, proteins from the dentate gyrus were separated by two-dimensional gel electrophoresis and stained with Pro-Q Diamond, a fluorescent stain specific for phosphoproteins.
The present study investigated a potential role for glucocorticoid (GR) and mineralocorticoid (MR) receptors in the detrimental effects of single cocaine (COC) administration on both the number of polysialylated neural cell adhesion molecule (PSA-NCAM)-positive neurons and the induction of long-term potentiation (LTP) in the rat dentate gyrus (DG).
Histopathological damage of the hippocampus and the volume of the dentate gyrus were assessed by HE-staining. With immunohistochemistry BrdU-positve cells were detected in the dentate gyrus.
We found expression of GPR30 in pyramidal cells of CA1-3 and granule cells of the dentate gyrus at both mRNA and protein levels.
Specifically, there was an increase in FGFR1 mRNA in the dentate gyrus 24 h post-FGF2, suggesting the potential for self-amplification of the initial signal.
In the present study, we quantified the number of neurons in the dentate gyrus granule layer (GCL) in 2- and 12-month-old APP/PS1KI mice, a mouse model that has been previously shown to have significant loss of neurons in the CA1 layer of the hippocampus.
Total RNA was isolated from microdissected dentate gyrus and processed for RT-PCR and qrtPCR using glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as an endogenous control gene.
Here, we show that intrahippocampal infusion of antibodies targeted to endogenous sAPP alpha reduced long-term potentiation (LTP) in the dentate gyrus of adult rats by approximately 50%.
The aim of the present study was to investigate the expression of the calcium binding proteins, calbindin-D28K, calretinin and parvalbumin in the dentate gyrus (DG) of amyloid precursor protein (APP)/presenilin 1 (PS1) transgenic (Tg) mice and their non-Tg littermates, as well as the relation with the deposition of human amyloid beta (Abeta).
The number of newborn neuronal precursors and endothelial cells was quantified in the subgranular zone (SGZ) and the molecular layer (ML) of the dentate gyrus.
An antisense probe to the B and C variants strongly labeled granule neurons in the dentate gyrus of the hippocampus, and cells in the granule layer and Purkinje layer (e.g. Based on co-localization studies with antibodies to neuronal or astrocytic markers, alphaA/B labeled neurons in the pyramidal layer and dentate gyrus of the hippocampus, as well as cortex. alphaC labeled glia surrounding neurons (and possibly neurons) in the neuropil of the Purkinje cell layer of the cerebellum, the pyramidal cell layer and dentate gyrus of the hippocampus, and the cortex.
Stromal cell-derived factor-1 (SDF-1) and its receptor CXC chemokine receptor 4 (CXCR4) are important regulators of the development of the dentate gyrus (DG).
The number of TUNEL-positive apoptotic nuclei in the dentate gyrus (DG) was increased 6-12 h after acute gamma-irradiation (a single dose of 0.5 to 4 Gy).
Analysing the morphology and cell phenotype by confocal microscopy, we confirmed the colocalization of the neurogenic markers (bromodeoxyuridine-neuronal nuclei-TOPRO-3) in newborn cells associated to vascular walls in CA1 and dentate gyrus of hippocampus 32 days after ischemia.
Here, we have conducted an electron microscopic examination of the subcellular distribution of the 5-HT1BR, NMDA receptor subunit NR1 and neurotransmitter gamma-aminobutyric acid (GABA), within the hippocampal dentate gyrus. These findings indicate that within the dentate gyrus, pre-synaptic 5-HT1BRs may modulate non-GABAergic neurotransmitter release whilst post-synaptic 5-HT1BRs are expressed on segments of mainly NR1 negative granule cell processes.
Trimethyltin chloride (TMT) is known to produce neuronal damage in the dentate gyrus at least in part via oxidative stress. Temporary depletion of endogenous glutathione by the prior subcutaneous injection of 2-cyclohexen-1-one was effective in facilitating neuronal damage and DJ-1 up-regulation in the dentate gyrus induced by an intraperitoneal injection of TMT at the dose of 2.0 mg/kg.
Here, we studied differential expression of MMP9/2 in the neurogenic niche of the hippocampal dentate gyrus (DG) after transient global brain ischemia in young adult macaque monkeys.
nNOS immunoreactive (nNOS-IR) positive neurons were observed in hippocampus CA1, CA2-3 regions and the dentate gyrus.
The dentate gyrus of the hippocampus generates neurons throughout life, but adult neurogenesis exhibits a marked age-dependent decline. We have used retroviral labelling of neural progenitor cells of the adult mouse dentate gyrus to study morphological properties of neurons born at different ages.
EE increased the immunoreactivity for doublecortin (DCX), a marker for immature neuron-positive cells, in the dentate gyrus (DG).
The significant increase in depression-like behavior during abstinence was associated with a reduction in proliferating cell nuclear antigen (PCNA) and doublecortin (DCX) immunoreactivity in the dentate gyrus of the hippocampus indicating that both the number of proliferating neural progenitor cells (NPC) and immature neurons were reduced, respectively.
Neural proliferation in the dentate gyrus of the hippocampus was suppressed by restraint stress, as observed by 5-bromo-2'-deoxyuridine incorporation and Ki-67 immunostaining, proliferation markers.
In nonresponders, decreased subunit staining was observed in CA1, CA2, CA3, and dentate gyrus, whereas much less widespread alterations were determined in responders.
In this study, the effects of amphetamine exposure during a portion of the brain growth spurt on the total number of hippocampal pyramidal cells (CA1/CA3 subregions) and the granule cells (dentate gyrus) were examined in both neonatal and adult rats. However, amphetamine significantly altered the rate of neuronal incorporation in both the hippocampal CA3 subregion and the dentate gyrus, and this effect appeared to be dose-related with the most robust effect observed in the highest amphetamine dose.
In the mammalian hippocampus, the dentate gyrus (DG) is characterized by sparse and powerful unidirectional projections to CA3 pyramidal cells, the so-called mossy fibers (MF).
RESULTS: Compared to the control, the accumulated optical density (AOD) of GABAAR alpha1 subunit immunoreactivity (IR) in the parietal cortex, the CA3-CA4 regions and the dentate gyrus in seizure rats increased significantly 1 day after recurrent seizures (P<0.05). The AOD of GABAAR alpha1 subunit IR in the parietal cortex, the CA1-CA4 regions and the dentate gyrus in seizure rats increased significantly 7 days after recurrent seizures compared with the control (P<0.05).
Although the cellular mechanisms underlying amelioration of particular symptoms are mostly unknown, recent studies have shown critical importance of the dentate gyrus of the hippocampus in behavioral effects of SSRIs in rodents.
In this study, we investigated the involvement of each individual subtypes of mAChR in LTP induction by intrahippocampal administration of cholinergic ligands at the dentate gyrus (DG) of anesthetized rats.
Flattening the diurnal corticosterone rhythm prevented the stimulating action of L-NAME (a nitric oxide synthase, NOS, inhibitor) on progenitor cell proliferation in the dentate gyrus in Lister-Hooded adult male rats. The increased expression of brain-derived neurotrophic factor (BDNF) and trkB mRNA in the dentate gyrus which otherwise occurred after L-NAME was also prevented by clamping the corticoid rhythm in adrenalectomized rats, but was restored by daily additional injections of corticosterone (which replicates the diurnal rhythm). Unilateral infusions of BDNF into the lateral ventricle increased proliferation in the dentate gyrus on the side of the infusion, but this was not observed following implantation of subcutaneous corticosterone, which flattened the diurnal corticosterone rhythm. 5HT1A mRNA in the dentate gyrus was increased on both sides of the brain by unilateral BDNF infusions, but this was also prevented by subcutaneous corticosterone pellets. These results show that the diurnal rhythm of corticosterone regulates the stimulating action of NOS inhibitors on BDNF as well as on neurogenesis in the dentate gyrus, and that BDNF becomes ineffective on both proliferation rates and 5HT1A expression in the absence of a rhythm in corticosterone.
We found that beta1AR-expressing interneurons were more prevalent in the CA3 and CA1 regions of the hippocampus than in the dentate gyrus, where they were relatively sparse. A high proportion of neuropeptide Y-containing interneurons in the dentate gyrus co-expressed beta2AR.
In this model of temporal lobe epilepsy, both protein kinase inhibitors diminished the acute epileptic activity triggered by KA and the ensuing morphological alterations in the dentate gyrus without diminishing cell loss.
Previously, we showed that daytime restricted access to a highly palatable complete meal replacement, Ensure Plus (Ensure), shifts the rhythm of expression of the clock protein PER2 in limbic forebrain areas including the oval nucleus of the bed nucleus of the stria terminalis (BNSTov), central nucleus of the amygdala (CEA), basolateral amygdala (BLA) and dentate gyrus (DG), and induces a rhythm in the dorsomedial hypothalamic nucleus (DMH) in food deprived (restricted feeding), but not free-fed rats (restricted treat).
We observed strikingly different levels of global methylation in the adult rat dentate gyrus (DG) and CA1 region in comparison with the CA2 and CA3 regions.
Changes in gene expression differed among cingulate cortex (CC), amygdala (AMY) and dentate gyrus (DG) and were extensively reversed by both drugs in CC and AMY, and to a lesser extent in DG.
Entorhinal cortex, subiculum, CA1, CA1-CA2 transition zone, CA3-4 and dentate gyrus (CA3&DG) and total hippocampal volume were determined using a manual marking strategy.
In the hippocampus, secretin was expressed in the dentate gyrus, the hilus, and the molecular layer.
Levels of alpha1d ADR mRNA were profoundly decreased in hippocampal subfields CA1, CA2 and CA3 and the medial and lateral blades of the dentate gyrus, as early as 1day after ADX, as determined by in situ hybridization.
The dentate gyrus is one of the few brain regions that show proliferation of neuronal precursors postnatally and in adult life. Proliferation in the dentate gyrus has been shown to be influenced by exercise, stress and drugs such as antidepressants. Here we adapted the Metamorph software to automatically count cells labeled in the S phase in the developing dentate gyrus of mice.
Recently, it has been reported that layer II entorhinal cortical cells, which mediate the majority of the cortical inputs to the dentate gyrus (DG), located at the gate of the hippocampus, fire with theta phase precession according to a grid-like pattern.
Supporting antidepressant properties, chronic (2-5 weeks) administration of S32006 suppressed "anhedonia" in a chronic mild stress procedure and increased both expression of BDNF and cell proliferation in rat dentate gyrus.
Neurogenesis in the dentate gyrus was severely reduced both in the premigratory and migratory progenitor pool. The lower number of progenitors in the dentate gyrus was not rescued after migration to the subgranular zone and thus the dentate gyrus lacked the entire internal blade and a part of the external blade from postnatal to adult stages..
It was restricted to the dentate gyrus and entorhinal cortex in approximately 75% of cases; approximately 25% showed more widespread TDP-43 pathology in frontal and temporal cortices, resembling the FTLD-U subtype associated with progranulin mutations.
In the mammalian brain, this process occurs in two discrete regions, the subventricular zone of the lateral ventricule (SVZ) and the subgranular zone of dentate gyrus (SGZ) in the hippocampus.
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