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全文: "hippocampal formation"
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  • Mi-Ae JUNG, Sang-Soep NAHM, Min-Su LEE, In-Hye LEE, Ah-Ra LEE, Dong-Pyo JANG, Young-Bo KIM, Zang-Hee CHO, Ki-Dong EOM
    Journal of Veterinary Medical Science
    2010年 72 巻 7 号 853-860
    発行日: 2010年
    公開日: 2010/08/04
    [早期公開] 公開日: 2010/02/24
    ジャーナル フリー
    This study was performed to anatomically illustrate the living canine hippocampal formation in three-dimensions (3D), and to evaluate its relationship to surrounding brain structures. Three normal beagle dogs were scanned on a MR scanner with inversion recovery segmented 3D gradient echo sequence (known as MP-RAGE: Magnetization Prepared Rapid Gradient Echo). The MRI data was manually segmented and reconstructed into a 3D model using the 3D slicer software tool. From the 3D model, the spatial relationships between hippocampal formation and surrounding structures were evaluated. With the increased spatial resolution and contrast of the MPRAGE, the canine hippocampal formation was easily depicted. The reconstructed 3D image allows easy understanding of the hippocampal contour and demonstrates the structural relationship of the hippocampal formation to surrounding structures in vivo.
  • NAGAYASU OTSUKA, TOSHIHIKO KISHIMOTO, TAKASHI NAGITA
    ACTA HISTOCHEMICA ET CYTOCHEMICA
    1976年 9 巻 2 号 107-110
    発行日: 1976年
    公開日: 2009/10/28
    ジャーナル フリー
    The hippocampal formation of monkey was studied by sulfide silver technique. Intense positive reaction to this method was found in the stratum radiatum of h3, h4 and h5 of the hippocampus, as well as the stratum multiforme of the fascia dentata. All these areas correspond to the endings of mossy fibers at the apical dendrite of pyramidal cells in the hippocampal formation.
  • NAGAYASU OTSUKA, KEIKI YOSHITAKE, HIDEO KUROKAWA, TETSUHIRO TAKAGI, RYOUICHI TOBITA, TADASHI YAMASAKI
    Okajimas Folia Anatomica Japonica
    1982年 58 巻 4-6 号 933-943
    発行日: 1982年
    公開日: 2012/09/24
    ジャーナル フリー
    Zinc in the hippocampal formation was studied by the sulfide silver method at 5,10,15, and 30 min after administration of 200 mg/kg oxine in rats. Specimens obtained at the same stages were also investigated electron microscopically.
    In rats at 5 min after the oxine administration, areas with a normal positive reaction for zinc, h3-h5 the of the hippocampal formation adjacent to the stratum pyramidale of the stratum radiatum and stratum multifome of the dentate gyrus, gave a negative reaction. At 15 min after the administration, a slightly positive reaction was noted, and an intense positve reaction was observed at 30 min after the administration.
    Electron microscopy revealed a marked decrease of synaptic vesicles in the mossy fiber endings of the rats at 5 min after the oxine administration. At 15 min after the administration, the synaptic vesicles in the mossy fiber endings were considerably increased. At 30 min after the administration, synaptic vesicles were densely accumulated within the endings as in normal animals.
  • NAGAYASU OTSUKA, HARUMITSU OKANO, KOBUN YOKOYAMA
    ACTA HISTOCHEMICA ET CYTOCHEMICA
    1975年 8 巻 3 号 175-176
    発行日: 1975年
    公開日: 2009/10/28
    ジャーナル フリー
  • FUMIO NASU
    ACTA HISTOCHEMICA ET CYTOCHEMICA
    1983年 16 巻 4 号 368-373
    発行日: 1983年
    公開日: 2010/02/26
    ジャーナル フリー
    The localization of ouabain-sensitive, K+-dependent p-nitrophenylphosphatase (K+-NPPase) activity, a part of the reaction of the Na+-K+-ATPase complex, was ultracytochemically investigated in the rat hippocampal formation called substantia gelatinosa cerebri. Microslicer sections of the hippocampal formation fixed with a mixture of 0.25% glutaraldehyde and 1% paraformaldehyde for 30 min were incubated in the medium for K+-NPPase.
    In the light microscopic observations, the most abundant reaction products were present in the stratum moleculare of the hippocampal formation. Electron microscopically, K+-NPPase activity was demonstrated on the axolemma, neurofilamentous structures in the axoplasm and synaptic plasma membrane. These activities were distinctly decreased with addition of 10 mM ouabain or substitution of Na+ for K+. Additionally, ouabain-insensitive, K+-independent p-NPPase activity was observed on the mitochondria, nuclear envelope and endoplasmic reticulum. Neurotubules did not show any K+-NPPase activity.
  • Yasukazu NAGATO, Masaki SEKIGUCHI, Hiroshi KUSHIDA, Kazuyo SHIMAI
    Okajimas Folia Anatomica Japonica
    1991年 68 巻 5 号 299-304
    発行日: 1991年
    公開日: 2012/09/24
    ジャーナル フリー
    To facilitate improvement of investigations on the distribution of mossy fibers in the hippocampal formation, a method is described using Timm's stained preparations after methacrylate embedding with the hydrophilic resin, Quetol 523M. Fixation with a mixture of formaldehyde and glutaraldehyde yielded satisfactory staining results and good structural preservation. During the course of histochemical experiments employing Timm's staining, examinations revealed that sulfide silver reaction products were consistently present in both the mossy fibers themselves and their terminals associated with the dendrites of pyramidal cells in tissue sections of 1-2μm in thickness. The results obtained also revealed that variations of the mossy fiber system occurred in the neurological mutant mouse dreher (dr). The bundles of mossy fibers forming the intrapyramidal synaptic field may be considered to reflect genotype-dependent differences in the mutation. The present method is adequate for allowing the histochemical demonstration of mossy fibers and their giant boutons by light microscopy.
  • Tangeng MA, Hwei-Hsien CHEN, Dong K. LIM, Arthur S. HUME, Ing K. HO
    The Journal of Toxicological Sciences
    1998年 23 巻 SupplementII 号 181-183
    発行日: 1998/07/24
    公開日: 2008/02/21
    ジャーナル フリー
    The NMDA receptor non-competitive antagonist, [3H] MK-801, was used as a ligand for an autoradiographic study to determine the effects of lead on NMDA receptor in rat brain. Adult male rats were given lead acetate, 100 mg/kg, or sodium acetate, 36 mg/kg (control), by i. p. for 7 days. Lead levels were detected in blood (41.1μg/dl) and brain (16.7-29.4μg/g). Concentrations of lead in various brain regions did not differ. [3H] MK-801 binding was heterogeneous throughout the brain with the following order of binding densities : hippocampal formation>cortex>caudate-putamen>thalamus>brainstem. Lead exposure caused a decrease in [3H] MK-801 binding to NMDA receptors in the hippocampal formation including CA2 stratum radiatum, CA3 stratum radiatum and presubiculum, and in the agranular insular, cingulate, entorhinal, orbital, parietal and perihinal areas of cerebral cortex. In another experiment, female rates were exposed pre-and post-natally from the 4th±1 post cconception day with 1, 000 ppm lead in their drinking water. This treatment continued after weaning. No effects of lead on [3H] MK-801 binding were found at postnatal day (PM) 28. However, lead caused a significant increase in [3H] MK-801 binding in the hippocampus including CA1 and CA2, and in the occipital and temporal cortical areas at PN 56 and at PN 112. Increases in [3H] MK-801 binding were also found in entorhinal cortex and dentate gyrus at PN 112. The hippocampal formation is a critical neural structure for learning and memory processes, whereas cortical and subcortical regions are involved in the modulation of complex behavioral processes. NMDA receptors have been shown to play a key role in synaptic plasticity underlying learning and memory. Therefore, lead-induced alterations of ligand binding to NMDA receptors in the hippocampal formation and cortical areas may play a role in lead-induced neurotoxicity.
  • Shigeo OKINAKA, Hiroshi IBAYASHI, Kenji MOTOHASHI, Takuo FUJITA, Nakaaki OHSAWA, Shoichiro MURAKAWA
    Neurologia medico-chirurgica
    1960年 2 巻 1-2 号 110-115
    発行日: 1960年
    公開日: 2007/05/25
    ジャーナル フリー
  • YASUHIKO IBATA, TADAO MATSUURA, HIROKO L. OBATA, HARUO KINOSHITA, KIMINAO MIZUKAWA
    Okajimas Folia Anatomica Japonica
    1982年 58 巻 4-6 号 891-921
    発行日: 1982年
    公開日: 2012/09/24
    ジャーナル フリー
    The hippocampal formation of the monkey (Macaca fuscata) was investigated by electron microscopy. Our attention was directed to the fine structure of the pyramidal cells in CA 3, CA 4 and of the mossy fiber endings. In addition to ordinary cell organelles, coated vesicles and subsurface cisterns were frequently observed in the pyramidal cells. We could find the initial segment of the axon of the pyremidal cells in CA 3 and moreover on the surface of it we could detect mossy fiber endings as well as Gray's type II synapses. The structure of the mossy fiber endings was fundamentaly similar to that of other mammalia. Pyramidal cells were frequently covered with mossy fiber endings, some of which terminated on neuronal somata as axo-somatic synapses. We observed dark mossy fiber endings which contained many dark synaptic vesicles and mitochondria. We also demonstrated a feature of protrusion of dendritic spines into the mossy fiber endings by serial sections. Small axo-somatic, axo-dendritic and axo-spinodendritic synapses were observed in the hilus fascia dentatae, CA 4, and in the strata radiata and pyramidale of CA 3. We classified these into two types, S and F, according to the shape of the synaptic vesicles they contained. By using Timm's sulfide-silver method under electron microscopic level dark precipitations due to the presence of zinc were found in preterminal regions of both ordinary and dark mossy fiber endings. Their distribution seemed to be restricted to synaptic vesicles as they were not seen in mitochondria. We also found dark precipitations in the small preterminal boutons distinct from mossy fiber endings.
  • 福山 右門, 松本 健五郎
    The Tohoku Journal of Experimental Medicine
    1950年 52 巻 1-2 号 69-75
    発行日: 1950/05/31
    公開日: 2008/11/28
    ジャーナル フリー
  • Toshiaki Omori, Tsuyoshi Horiguchi
    Journal of the Physical Society of Japan
    2002年 71 巻 6 号 1598-1604
    発行日: 2002年
    公開日: 2003/04/25
    ジャーナル 認証あり
    We investigate some noise effect on a neural network model proposed by Araki and Aihara for the memory recall of dynamical patterns in the hippocampus and the entorhinal cortex; the noise effect is important since the release of transmitters at synaptic clefts, the operation of gate of ion channels and so on are known as stochastic phenomena. We consider two kinds of noise effect due to a deterministic noise and a stochastic noise. By numerical simulations, we find that reasonable values of noise give better performance on the memory recall of dynamical patterns. Furthermore we investigate the effect of the strength of external inputs on the memory recall.
  • S. WATANABE
    Neurologia medico-chirurgica
    1961年 3 巻 1-2 号 161
    発行日: 1961年
    公開日: 2007/05/30
    ジャーナル フリー
  • NAGAYASU OTSUKA, HARUMITSU OKANO, HISAYUKI SHOBATAKE, YASUHIKO IBATA
    ACTA HISTOCHEMICA ET CYTOCHEMICA
    1975年 8 巻 2 号 91-98
    発行日: 1975年
    公開日: 2009/10/28
    ジャーナル フリー
    Electron microscopic observations were made of the mossy fiber endings distributed in the hippocampal formation of rats receiving dithizone and of normal controls.
    The mossy fiber endings were noted to be enlarged to form terminal synaptic knobs complex in shape, each surrouding a dendritic spine. The synaptic knob contained synaptic vesicles. The portion of the presynaptic membrane of the knob facing a dendritic spine appeared to be markedly thick whereas that of the presynaptic membrane in contact with the smooth surface of a dendrite was not notably thick.
    Sections taken at 15 and 30minutes after administration of dithizone frequently showed remarkably dense accumulations of synaptic vesicles in parts of the terminal knobs of mossy fibers.
    At 1 and 1.5hours after dithizone, there was evidence of drastic diminution of the synaptic vesicles in the mossy fiber endings and, concomitantly with it, the dendritic spines were seen to have decreased.
    The morphologic features of the mossy fiber ending, however, returned almost completely to the normal state by 3 to 5hours after dithizone.
    An attempt was made to investigate the interrelation of these ultra-structural alterations with zinc and the mechanism of action of dithizone on the mossy fiber ending has been discussed.
  • Ilgaz Akdogan, Esat Adiguzel, Gunfer Turgut, Osman Genc, A. Cevik Tufan
    The Tohoku Journal of Experimental Medicine
    2005年 205 巻 2 号 171-178
    発行日: 2005年
    公開日: 2005/01/27
    ジャーナル フリー
    Copper (Cu) is an essential element for life, however, is toxic at excessive doses, whereas exposure to ethanol (EtOH) has been known to cause morphological changes, degeneration and neuronal loss in central nervous system (CNS). In this study, the effect of overdose co-exposure to Cu and EtOH on dentate gyrus was investigated in rats. Analysis of apoptotic cell death on the basis of TdT-mediated dUTP nick end labeling (TUNEL) assay revealed that the rate of apoptosis was increased by 1.84 folds in treated group in comparison to that in controls (p < 0.0001). Analysis of cell proliferation on the basis of 5-bromo-2'-deoxy-uridine labeling assay, on the other hand, revealed a 1.49 fold increase in treated group when compared to controls (p < 0.006). Total number of granule cells in dentate gyrus of each group was estimated using the optical fractionator method. The results showed that mean granule cell number in dentate gyrus was 4.64% lower in treated group than that in control group, but this difference was not statistically significant (p > 0.05). These results suggest that the apoptotic effect of overdose Cu and EtOH on granule cells of dentate gyrus may be counterbalanced by the co-induced cellular proliferation, thereby maintaining the total granule cell number unaltered.
  • 小幡 裕子, 久保 清一, 木下 晴生, 村部 義則, 井端 泰彦
    Archivum histologicum japonicum
    1981年 44 巻 2 号 135-149
    発行日: 1981年
    公開日: 2009/02/20
    ジャーナル フリー
    少量のカイニン酸をラットの側脳室に投与し, 海馬CA3野に対する影響について、投与1時間後より3週後まで, 経時的に電顕により観察を行なった. 投与後, 3時間くらいより, 激しい変性が錐体細胞の細胞体や樹状突起に認められた. 錐体細胞の変性は, 大きく4種類に分けられ, おそらくカイニン酸に対する感受性を反映していると考えられる. また, 今回の実験で, 錐体細胞の変性に加えて, 軸索の終末や終末前軸索に変性が認められた. 歯状回からの突起である苔状線維の終末には, 初期において形態上変化をみとめ, また, 苔状線維終末どうしのシナプスと考えられる構造も認められた. CA3野の変性に応じて, グリアの反応も激しく, 初期においては星状膠細胞や大食細胞が増加し, 変性後の組織には小膠細胞や星状膠細胞が動員されていた.
  • ATSUSHI TAKEDA, JINKO SAWASHITA, SHOJI OKADA
    衛生化学
    1995年 41 巻 1 号 P49
    発行日: 1995/02/28
    公開日: 2008/05/30
    ジャーナル フリー
  • KEIJI SANO, TAKAAKI KIRINO
    The Tohoku Journal of Experimental Medicine
    1990年 161 巻 Supplement 号 273-295
    発行日: 1990年
    公開日: 2011/03/14
    ジャーナル フリー
    Sclerosis of the cornu Ammonis or Ammon's horn sclerosis (AHS) is an “often-described, yet hitherto enigmatic phenomen” as Spielmyer put it in 1927. It has been found in cases with ischemia, anoxia or hypoglycemia and in more than half of the epileptic brains examined at autopsy. Various theories about its pathogenesis have been propunded. Among them, the “Pathoklise” theory of the Vogts and the vascular theory of Spielmeyer and his associates were prevailing until recently. In 1953, two articles were published to contribute to the pathogenesis of ictal automatism (a type of complex partial or temporal lobe seizures). One is the incisural sclerosis theory by Penfield and his associates and the other is the Ammon's horn sclerosis theory by Sano and Malamud. The former authors described a diffuse sclerosis of the infero-mesial temporal structures without, however, specifically relating it to AHS. They considered it was the result of localized anoxia of that portion of the brain caused by incisural herniation occurring during parturition. Sano and Malamud maintained that AHS is a result of convulsions, a distinct scar adjacent to which epileptogenic foci may develop in the course of time to cause ictal antomatism. The latter theory was corroborated by Sano, Falconer and others. Falconer expanded the theory to the assertion that not only ictal automatism but other types of intractable epilepsy may be due to “mesial temporal (Ammon's horn) sclerosis”. The most recent development in the pathogenesis of AHS is the excitotoxicity theory. Namely, AHS is caused by excessive excitation of neurons, probably by putative excitatory neurotransmitters, especially, glutamate. For this theory, there is a significant body of evidence. The problem of AHS, an old research subject and a matter of long-lasting controversy, has now been updated and become one of the newest topics in the field of experimental neurobiology.
  • MINORU OKITA, AKIO INUI, TORU INOUE, SHIGEAKI BABA
    Biomedical Research
    1990年 11 巻 1 号 67-71
    発行日: 1990/02/01
    公開日: 2015/08/01
    ジャーナル フリー
  • MITSUE TAKEYA, HIROSHI HASUO, NORIHIRO MURAOKA, TAKASHI AKASU
    The Kurume Medical Journal
    2001年 48 巻 3 号 205-210
    発行日: 2001/09/14
    公開日: 2009/08/11
    ジャーナル フリー
    Changes in the membrane potential of neurons in the hippocampal CA2 and CA1 regions were recorded by optical recording techniques. After stimulation of the Schaffer collaterals at the hippocampal CA2 region, excitatory optical signals first occurred adjacent stimulus electrode and then flamed-up signals spread toward the hippocampal CA1 region. The optical signal was blocked by tetrodotoxin (TTX) (1 μM). Propagation of the optical signal was blocked in an artificial cerebrospinal fluid (ACSF) containing 0 mM Ca2+ and 6 mM Mg2+. 6, 7-Dinitroquinoxaline-2, 3 (1 H, 4H)-dione (DNQX) (20 μM) also blocked the optical signals that spread to the hippocampal CA1 region. The time course of the optical signal recorded at a unit area (49 pixels) on the propagation pathway was characterized by fast and slow components. TTX (1 μM) blocked both fast and slow components of the optical signal. The slow component of the optical signal was preferentially depressed by either removal of external Ca2+ or by bath-application of DNQX (20 μM). When bicuculline (15 μM) was applied to the bath-solution, the intensity and propagation area of the optical signal were increased. The results indicate that stimulation of the Schaffer collaterals in the hippocampal CA2 region produces the propagation of the optical signal to the hippocampal CA1 region, and that the optical signal involves the action potential and excitatory and inhibitory postsynaptic potentials.
  • Mehmet Asim OZER, Gulgun KAYALIOGLU, Mete ERTURK
    Neurologia medico-chirurgica
    2005年 45 巻 12 号 607-613
    発行日: 2005年
    公開日: 2005/12/26
    ジャーナル オープンアクセス
    The topographic anatomy and morphometry of the fornix is important for standardizing the transcallosal-interforniceal approach and avoiding memory disturbances. The detailed morphometry of the fornix was investigated with a special emphasis on sex differences using midsagittal magnetic resonance imaging of 80 males and 102 females. Various parameters of the fornix, including the length of the upper and lower fornices, the curvature of the upper and lower fornices, and the insertion point of the fornix to corpus callosum, were investigated. The thickness of the fornix at the attachment point to the anterior commissure, the maximum distance to the upper and lower surfaces of the fornix, and the curvature of the upper and lower fornices showed sex differences (p < 0.5). The upper insertion point of the fornix to the corpus callosum was more frontal in females, but the functional relevance of these differences need further investigation.
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