Hippocampus最新文献

{"title":"Adult Neurogenesis in the Human Dentate Gyrus","authors":"Fred H. Gage","doi":"10.1002/hipo.23655","DOIUrl":"10.1002/hipo.23655","url":null,"abstract":"<div>\u0000 \u0000 <p>In the adult dentate gyrus of the hippocampus there are neuronal stem cells that give rise to immature neurons and subsequently to mature functional granule neurons. The rate of proliferation, differentiation, and survival is regulated intrinsically and extrinsically. For example, Wnt, BMP, TLX, and BDNF all regulate adult neurogenesis intrinsically, while exercise, environmental enrichment, stress, and epilepsy are some of the extrinsic factors that regulate adult neurogenesis. A clearer picture is emerging for the functional role of these newly born neurons in behavior, demonstrating that adult neurogenesis plays a role in recognizing events, places, objects, or people as unique when comparing options that are very similar, but that these newly born cells play little role in recognition when differences are greater. Most of the research on adult neurogenesis is conducted in experimental mammals, including mice and rats. The first evidence for adult neurogenesis in humans was reported in 1998, when postmortem brains from cancer patients injected with bromodeoxyuridine (BrdU) were examined and cells were found that had divided and differentiated into mature neurons. Subsequently, additional evidence using other techniques has confirmed human adult neurogenesis. Additional in vivo live reports will be needed to monitor the effects of changes in human adult neurogenesis with age and disease.</p>\u0000 </div>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"35 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142794486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Behavioral Consequences of Hippocampal 5-HT7 Receptors Blockade in Stressed Rats","authors":"Adriana Colsera Pereira,&nbsp;Júlia Lopes Gonçalez,&nbsp;Thalita Aparecida Riul Prado,&nbsp;Rodrigo Campos-Cardoso,&nbsp;Giovana Vieira Viais Zagatto,&nbsp;Pedro Guilherme Pauletti Lorenzo,&nbsp;Cláudia Maria Padovan","doi":"10.1002/hipo.23663","DOIUrl":"10.1002/hipo.23663","url":null,"abstract":"<div>\u0000 \u0000 <p>Serotonin (5-HT) has long been involved in response to stress and its effect may be, in part, mediated by 5-HT1a and 5-HT7 receptor subtypes in different brain structures. Both pre- and post-synaptic activation of 5-HT1a receptor, respectively, in the rat median raphe nucleus (MnRN) and hippocampus, lead to adaptation to acute inescapable stressors such as restraint and forced swim. 5-HT7 receptor (5HT7r), a stimulatory G-protein coupled receptor, has also been investigated as a possible candidate for mediating stress response. In the MnRN, activation of 5-HT7r has antidepressant effects, while in the hippocampus, 5HT7r mRNA expression is increased after exposure to restraint stress, but the functional significance of these receptors remains to be determined. Therefore, the aim of this study was to investigate whether blockade of hippocampal 5HT7r would prevent and/or attenuate the behavioral effects of stress. Male adult Wistar rats with bilateral cannulas aimed at the dorsal hippocampus were restrained for 2 h and tested in the elevated plus maze (EPM) 24 h later. SB 258741 (3 nmoles/0.5 μL/side; selective 5HT7r antagonist) was administered bilateraly into the hippocampus according to the experimental protocol: immediately before or after stress, or 24 h after it (immediately before the test). In a second experiment, rats were exposed to 15 min. of forced swim, and tested 24 h later. Intra-hippocampal treatment was performed as described for the restraint stress protocol. We found that blockade of hippocampal 5-HT7r immediately after, but not before, the exposure to restraint or forced swim attenuated stress-induced behavioral changes. Similar results were obtained when SB was administered before the test in previously stressed rats. Our data suggest that activation of hippocampal 5-HT7r is crucial for the consolidation and retrieval of aversive stimulus-related memories, such as those caused by a stressful experience, probably through mechanisms involving stress-induced changes in 5-HT7r expression.</p>\u0000 </div>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"35 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142791603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Explicit Memory, Implicit Memory, and the Hippocampus: Insights From Early Neuroimaging Studies","authors":"Daniel L. Schacter","doi":"10.1002/hipo.23657","DOIUrl":"10.1002/hipo.23657","url":null,"abstract":"<div>\u0000 \u0000 <p>During the 1980s and 1990s, much memory research focused on the differential role of the hippocampus in various forms of memory. My work on the distinction between explicit and implicit memory led me to become involved in several early neuroimaging studies that made use of cognitive paradigms to investigate the conditions in which hippocampal activity does and does not occur, and to address the theoretical implications of these findings. Here, I summarize two such projects and some of the personal backstory associated with them.</p>\u0000 </div>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"35 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142791605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Some Memories of Stalking the Seahorse","authors":"Lynn Nadel","doi":"10.1002/hipo.23656","DOIUrl":"10.1002/hipo.23656","url":null,"abstract":"<div>\u0000 \u0000 <p>Early influences that led to the development of the cognitive map theory of hippocampal function, and the multiple trace theory, are discussed. Some details are provided, many are left out.</p>\u0000 </div>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"35 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142791606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sparsity of Population Activity in the Hippocampus Is Task-Invariant Across the Trisynaptic Circuit and Dorsoventral Axis","authors":"J. Quinn Lee,&nbsp;Matt Nielsen,&nbsp;Rebecca McHugh,&nbsp;Erik Morgan,&nbsp;Nancy S. Hong,&nbsp;Robert J. Sutherland,&nbsp;Robert J. McDonald","doi":"10.1002/hipo.23651","DOIUrl":"https://doi.org/10.1002/hipo.23651","url":null,"abstract":"<p>Evidence from neurophysiological and genetic studies demonstrates that <i>activity sparsity</i>—the proportion of neurons that are active at a given time in a population—systematically varies across the canonical trisynaptic circuit of the hippocampus. Recent work has also shown that sparsity varies across the hippocampal dorsoventral (long) axis, wherein activity is sparser in ventral than dorsal regions. While the hippocampus has a critical role in long-term memory (LTM), whether sparsity across the trisynaptic circuit and hippocampal long axis is task-dependent or invariant remains unknown. Importantly, representational sparsity has significant implications for neural computation and theoretical models of learning and memory within and beyond the hippocampus. Here we used functional molecular imaging to quantify sparsity in the rat hippocampus during performance of the Morris water task (MWT) and contextual fear discrimination (CFD) – two popular and distinct assays of LTM. We found that activity sparsity is highly reliable across memory tasks, wherein activity increases sequentially across the trisynaptic circuit (DG &lt; CA3 &lt; CA1) and decreases across the long axis (ventral&lt;dorsal). These results have important implications for models of hippocampal function and suggest that activity sparsity is a preserved property in the hippocampal system across cognitive settings.</p>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"35 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hipo.23651","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Issue Information - Editorial Board","authors":"","doi":"10.1002/hipo.23613","DOIUrl":"https://doi.org/10.1002/hipo.23613","url":null,"abstract":"","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"35 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hipo.23613","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142748885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Decreases in K63 Polyubiquitination in the Hippocampus Promote the Formation of Contextual Fear Memories in Both Males and Females","authors":"Natalie J. Preveza,&nbsp;Gueladouan Setenet,&nbsp;Phillip Gwin,&nbsp;Yeeun Bae,&nbsp;Morgan B. Patrick,&nbsp;Adam Cummings,&nbsp;Jennifer R. Abraham,&nbsp;W. Keith Ray,&nbsp;Richard F. Helm,&nbsp;Timothy J. Jarome","doi":"10.1002/hipo.23650","DOIUrl":"https://doi.org/10.1002/hipo.23650","url":null,"abstract":"<div>\u0000 \u0000 <p>Over 90% of protein degradation in eukaryotic cells occurs through the ubiquitin-proteasome system (UPS). In this system, the ubiquitin protein can bind to a substrate on its own or it can form a chain with multiple ubiquitin molecules in a process called polyubiquitination. There are 8 different sites on ubiquitin at which polyubiquitin chains can be formed, the second most abundant of which, lysine-63 (K63), is independent of the degradation process, though this mark has rarely been studied in the brain or during learning-dependent synaptic plasticity. Recently, we found that knockdown of K63 polyubiquitination in the amygdala selectively impaired contextual fear memory formation in female, but not male, rats. It is unknown, however, whether the sex-specific requirement of K63 polyubiquitination occurs in other brain regions that are required for contextual fear memory formation, including the hippocampus. Here, we found that CRISPR-dCas13-mediated knockdown of K63 polyubiquitination in the hippocampus significantly enhanced contextual fear memory in both male and female rats, a result that is in striking contrast to what we observed in the amygdala for both sex-specificity and directionality. Using unbiased proteomics, we found that following fear conditioning K63 polyubiquitination was primarily decreased at target proteins in the hippocampus of both males and females. Importantly, the target proteins and downstream functional pathways influenced by K63 polyubiquitination changes diverged significantly by sex. Together, these data suggest that unlike what we previously reported in the amygdala, decreases in K63 polyubiquitination in the hippocampus are a critical regulator of memory formation in the hippocampus of both males and females.</p>\u0000 </div>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"35 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142748886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CORRECTION to “RETRACTION: Hippocampus of Ames Dwarf Mice is Resistant to β-Amyloid-Induced Tau Hyperphosphorylation and Changes in Apoptosis-Regulatory Protein Levels”","authors":"","doi":"10.1002/hipo.23649","DOIUrl":"10.1002/hipo.23649","url":null,"abstract":"<p>M. Schrag, S. Sharma, H. Brown-Borg, and O. Ghribi, “RETRACTION: Hippocampus of Ames Dwarf Mice is Resistant to β-Amyloid-Induced Tau Hyperphosphorylation and Changes in Apoptosis-Regulatory Protein Levels,” <i>Hippocampus</i> 18, no. 3 (2007): 239–244, https://doi.org/10.1002/hipo.23626.</p><p>In the above retraction notice, it was erroneously stated that Holly Brown-Borg did not respond. Brown-Borg did respond, and was unaware of Ghribi's actions and not in any way involved. Brown-Borg agrees with this decision.</p><p>The corrected retraction notice is:</p><p>The above article, published online on November 13, 2007 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor-in-Chief, Michael E. Hasselmo, and Wiley Periodicals LLC. The retraction has been agreed upon following an investigation by the authors' institution, the University of North Dakota, which determined that this article contains data that the corresponding author, Othman Ghribi, had fabricated. Matthew Schrag and Holly Brown-Borg were unaware of Ghribi's actions and not in any way involved, and they agree with this decision. Sunita Sharma and Othman Ghribi did not respond.</p><p>The online version of this retraction has been corrected accordingly.</p>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"35 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hipo.23649","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142716174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Issue Information - Editorial Board","authors":"","doi":"10.1002/hipo.23565","DOIUrl":"https://doi.org/10.1002/hipo.23565","url":null,"abstract":"","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"34 12","pages":"673"},"PeriodicalIF":2.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hipo.23565","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Supramammillary Theta Oscillations in Water Maze Learning","authors":"Calvin K. Young,&nbsp;Ming Ruan,&nbsp;Neil McNaughton","doi":"10.1002/hipo.23646","DOIUrl":"10.1002/hipo.23646","url":null,"abstract":"<div>\u0000 \u0000 <p>The supramammillary nucleus (SuM) in the hypothalamus, in conjunction with the hippocampus (HPC), has been implicated through theta oscillations in various brain functions ranging from locomotion to learning and memory. While the indispensable role of the SuM in HPC theta generation in anesthetized animals is well-characterized, the SuM is not always necessary for HPC theta in awake animals. This raises questions on the precise behavioral relevance of SuM theta activity and its interaction with HPC theta activity. We used simultaneously recorded SuM and HPC local field potentials (LFPs) in a one-day water maze (WM) learning paradigm in rats (<i>n</i> = 8), to show that theta activities recorded from the SuM itself were not positively correlated with locomotor (swimming) speed nor acceleration, but the individual relationship between acceleration and SuM theta frequency is correlated with WM learning rates. In contrast, we found that SuM-HPC theta phase coherence is strongly correlated with swimming speed and acceleration, but these do not relate to WM learning. SuM-HPC-directed coherence analysis demonstrated no swimming kinetics nor learning rate associations, but revealed that periods of high SuM-HPC theta phase coherence are driven by the SuM at relatively low (~6.2 Hz) frequencies. Additionally, we demonstrate that the SuM and the HPC also engage in non-random, non-coherent phase coupling modes where either structure preferentially displays a ± 2 Hz difference with the other. Our data indicate SuM theta LFPs do not appear to be related to either speed coding or spatial learning in swimming rats and display non-random out-of-phase theta frequency coupling with the HPC.</p>\u0000 </div>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"34 12","pages":"767-776"},"PeriodicalIF":2.4,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142582766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}