1
|
Shi W, Li M, Zhang T, Yang C, Zhao D, Bai J. GABA system in the prefrontal cortex involved in psychostimulant addiction. Cereb Cortex 2024; 34:bhae319. [PMID: 39098820 DOI: 10.1093/cercor/bhae319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 07/08/2024] [Accepted: 07/17/2024] [Indexed: 08/06/2024] Open
Abstract
Drug addiction is a chronic and relapse brain disorder. Psychostimulants such as cocaine and amphetamine are highly addictive drugs. Abuse drugs target various brain areas in the nervous system. Recent studies have shown that the prefrontal cortex (PFC) plays a key role in regulating addictive behaviors. The PFC is made up of excitatory glutamatergic cells and gamma-aminobutyric acid (GABAergic) interneurons. Recently, studies showed that GABA level was related with psychostimulant addiction. In this review, we will introduce the role and mechanism of GABA and γ-aminobutyric acid receptors (GABARs) of the PFC in regulating drug addiction, especially in psychostimulant addiction.
Collapse
Affiliation(s)
- Wenjing Shi
- Faculty of Life Science and Technology, Kunming University of Science and Technology, No. 727 Jingming South Road, Kunming 650500, Yunnan, China
- Medical School, Kunming University of Science and Technology, No. 727 Jingming South Road, Kunming 650500, Yunnan, China
| | - Minyu Li
- Medical School, Kunming University of Science and Technology, No. 727 Jingming South Road, Kunming 650500, Yunnan, China
| | - Ting Zhang
- Medical School, Kunming University of Science and Technology, No. 727 Jingming South Road, Kunming 650500, Yunnan, China
| | - Chunlong Yang
- Medical School, Kunming University of Science and Technology, No. 727 Jingming South Road, Kunming 650500, Yunnan, China
| | - Dongdong Zhao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, No. 727 Jingming South Road, Kunming 650500, Yunnan, China
- Medical School, Kunming University of Science and Technology, No. 727 Jingming South Road, Kunming 650500, Yunnan, China
| | - Jie Bai
- Medical School, Kunming University of Science and Technology, No. 727 Jingming South Road, Kunming 650500, Yunnan, China
| |
Collapse
|
2
|
Ingram R, Volianskis R, Georgiou J, Jane DE, Michael-Titus AT, Collingridge GL, Volianskis A. Incremental induction of NMDAR-STP and NMDAR-LTP in the CA1 area of ventral hippocampal slices relies on graded activation of discrete NMDA receptors. Philos Trans R Soc Lond B Biol Sci 2024; 379:20230239. [PMID: 38853568 PMCID: PMC11343233 DOI: 10.1098/rstb.2023.0239] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Revised: 04/12/2024] [Accepted: 04/12/2024] [Indexed: 06/11/2024] Open
Abstract
N-methyl-d-aspartate receptor (NMDAR)-dependent short- and long-term types of potentiation (STP and LTP, respectively) are frequently studied in the CA1 area of dorsal hippocampal slices (DHS). Far less is known about the NMDAR dependence of STP and LTP in ventral hippocampal slices (VHS), where both types of potentiation are smaller in magnitude than in the DHS. Here, we first briefly review our knowledge about the NMDAR dependence of STP and LTP and some other forms of synaptic plasticity. We then show in new experiments that the decay of NMDAR-STP in VHS, similar to dorsal hippocampal NMDAR-STP, is not time- but activity-dependent. We also demonstrate that the induction of submaximal levels of NMDAR-STP and NMDAR-LTP in VHS differs from the induction of saturated levels of plasticity in terms of their sensitivity to subunit-preferring NMDAR antagonists. These data suggest that activation of distinct NMDAR subtypes in a population of neurons results in an incremental increase in the induction of different phases of potentiation with changing sensitivity to pharmacological agents. Differences in pharmacological sensitivity, which arise due to differences in the levels of agonist-evoked biological response, might explain the disparity of the results concerning NMDAR subunit involvement in the induction of NMDAR-dependent plasticity.This article is part of a discussion meeting issue 'Long-term potentiation: 50 years on'.
Collapse
Affiliation(s)
- Rachael Ingram
- Centre for Neuroscience, Surgery and Trauma, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Rasa Volianskis
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - John Georgiou
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, Ontario, Canada
- TANZ Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
| | - David E. Jane
- Hello Bio Limited, Cabot Park, Avonmouth, Bristol, UK
| | - Adina T. Michael-Titus
- Centre for Neuroscience, Surgery and Trauma, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Graham L. Collingridge
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
- TANZ Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
| | - Arturas Volianskis
- Centre for Neuroscience, Surgery and Trauma, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff, UK
| |
Collapse
|
3
|
Tsotsokou G, Miliou A, Trompoukis G, Leontiadis LJ, Papatheodoropoulos C. Region-Related Differences in Short-Term Synaptic Plasticity and Synaptotagmin-7 in the Male and Female Hippocampus of a Rat Model of Fragile X Syndrome. Int J Mol Sci 2024; 25:6975. [PMID: 39000085 PMCID: PMC11240911 DOI: 10.3390/ijms25136975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Revised: 06/22/2024] [Accepted: 06/24/2024] [Indexed: 07/16/2024] Open
Abstract
Fragile X syndrome (FXS) is an intellectual developmental disorder characterized, inter alia, by deficits in the short-term processing of neural information, such as sensory processing and working memory. The primary cause of FXS is the loss of fragile X messenger ribonucleoprotein (FMRP), which is profoundly involved in synaptic function and plasticity. Short-term synaptic plasticity (STSP) may play important roles in functions that are affected by FXS. Recent evidence points to the crucial involvement of the presynaptic calcium sensor synaptotagmin-7 (Syt-7) in STSP. However, how the loss of FMRP affects STSP and Syt-7 have been insufficiently studied. Furthermore, males and females are affected differently by FXS, but the underlying mechanisms remain elusive. The aim of the present study was to investigate possible changes in STSP and the expression of Syt-7 in the dorsal (DH) and ventral (VH) hippocampus of adult males and females in a Fmr1-knockout (KO) rat model of FXS. We found that the paired-pulse ratio (PPR) and frequency facilitation/depression (FF/D), two forms of STSP, as well as the expression of Syt-7, are normal in adult KO males, but the PPR is increased in the ventral hippocampus of KO females (6.4 ± 3.7 vs. 18.3 ± 4.2 at 25 ms in wild type (WT) and KO, respectively). Furthermore, we found no gender-related differences, but did find robust region-dependent difference in the STSP (e.g., the PPR at 50 ms: 50.0 ± 5.5 vs. 17.6 ± 2.9 in DH and VH of WT male rats; 53.1 ± 3.6 vs. 19.3 ± 4.6 in DH and VH of WT female rats; 48.1 ± 2.3 vs. 19.1 ± 3.3 in DH and VH of KO male rats; and 51.2 ± 3.3 vs. 24.7 ± 4.3 in DH and VH of KO female rats). AMPA receptors are similarly expressed in the two hippocampal segments of the two genotypes and in both genders. Also, basal excitatory synaptic transmission is higher in males compared to females. Interestingly, we found more than a twofold higher level of Syt-7, not synaptotagmin-1, in the dorsal compared to the ventral hippocampus in the males of both genotypes (0.43 ± 0.1 vs. 0.16 ± 0.02 in DH and VH of WT male rats, and 0.6 ± 0.13 vs. 0.23 ± 0.04 in DH and VH of KO male rats) and in the WT females (0.97 ± 0.23 vs. 0.31 ± 0.09 in DH and VH). These results point to the susceptibility of the female ventral hippocampus to FMRP loss. Importantly, the different levels of Syt-7, which parallel the higher score of the dorsal vs. ventral hippocampus on synaptic facilitation, suggest that Syt-7 may play a pivotal role in defining the striking differences in STSP along the long axis of the hippocampus.
Collapse
Affiliation(s)
| | | | | | | | - Costas Papatheodoropoulos
- Lab of Physiology-Neurophysiology, Department of Medicine, University of Patras, 265 04 Patras, Greece; (G.T.); (A.M.); (G.T.); (L.J.L.)
| |
Collapse
|
4
|
Tsotsokou G, Trompoukis G, Papatheodoropoulos C. Muscarinic Modulation of Synaptic Transmission and Short-Term Plasticity in the Dorsal and Ventral Hippocampus. Mol Cell Neurosci 2024; 129:103935. [PMID: 38703973 DOI: 10.1016/j.mcn.2024.103935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 04/29/2024] [Accepted: 04/30/2024] [Indexed: 05/06/2024] Open
Abstract
Muscarinic neurotransmission is fundamentally involved in supporting several brain functions by modulating flow of information in brain neural circuits including the hippocampus which displays a remarkable functional segregation along its longitudinal axis. However, how muscarinic neuromodulation contributes to the functional segregation along the hippocampus remains unclear. In this study we show that the nonselective muscarinic receptor agonist carbachol similarly suppresses basal synaptic transmission in the dorsal and ventral CA1 hippocampal field, in a concentration-depended manner. Furthermore, using a ten-pulse stimulation train of varying frequency we found that carbachol changes the frequency filtering properties more in ventral than dorsal hippocampus by facilitating synaptic inputs at a wide range of input frequencies in the ventral compared with dorsal hippocampus. Using the M2 receptor antagonist gallamine and the M4 receptor antagonist tropicamide, we found that M2 receptors are involved in controlling basal synaptic transmission and short-term synaptic plasticity (STSP) in the ventral but not the dorsal hippocampus, while M4 receptors participate in modulating basal synaptic transmission and STSP in both segments of the hippocampus. These results were corroborated by the higher protein expression levels of M2 receptors in the ventral compared with dorsal hippocampus. We conclude that muscarinic transmission modulates excitatory synaptic transmission and short-term synaptic plasticity along the entire rat hippocampus by acting through M4 receptors and recruiting M2 receptors only in the ventral hippocampus. Furthermore, M4 receptors appear to exert a permissive role on the actions of M2 receptors on STSP in the ventral hippocampus. This dorsoventral differentiation of muscarinic modulation is expected to have important implications in information processing along the endogenous hippocampal circuitry.
Collapse
Affiliation(s)
- Giota Tsotsokou
- Laboratory of Physiology, University of Patras, Department of Medicine, Rion, Greece
| | - George Trompoukis
- Laboratory of Physiology, University of Patras, Department of Medicine, Rion, Greece
| | | |
Collapse
|
5
|
Tsotsokou G, Kouri V, Papatheodoropoulos C. α7 nicotinic acetylcholine receptors induce long-term synaptic enhancement in the dorsal but not ventral hippocampus. Synapse 2024; 78:e22285. [PMID: 38287475 DOI: 10.1002/syn.22285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 11/08/2023] [Accepted: 12/04/2023] [Indexed: 01/31/2024]
Abstract
Agents that positively modulate the activity of α7nAChRs are used as cognitive enhancers and for the treatment of hippocampus-dependent functional decline. However, it is not known whether the expression and the effects of α7nAChRs apply to the entire longitudinal axis of the hippocampus equally. Given that cholinergic system-involving hippocampal functions are not equally distributed along the hippocampus, we comparatively examined the expression and the effects of α7nAChRs on excitatory synaptic transmission between the dorsal and the ventral hippocampal slices from adult rats. We found that α7nAChRs are equally expressed in the CA1 field of the two segments of the hippocampus. However, activation of α7nAChRs by their highly selective agonist PNU 282987 induced a gradually developing increase in field excitatory postsynaptic potential only in the dorsal hippocampus. This long-term potentiation was not reversed upon application of nonselective nicotinic receptor antagonist mecamylamine, but the induction of potentiation was prevented by prior blockade of α7nAChRs by their antagonist MG 624. In contrast to the long-term synaptic plasticity, we found that α7nAChRs did not modulate short-term synaptic plasticity in either the dorsal or the ventral hippocampus. These results may have implications for the role that α7nAChRs play in specifically modulating functions that depend on the normal function of the dorsal hippocampus. We propose that hippocampal functions that rely on a direct α7 nAChR-mediated persistent enhancement of glutamatergic synaptic transmission are preferably supported by dorsal but not ventral hippocampal synapses.
Collapse
Affiliation(s)
- Giota Tsotsokou
- Department of Medicine, Laboratory of Physiology, University of Patras, Rion, Greece
| | - Vasiliki Kouri
- Department of Medicine, Laboratory of Physiology, University of Patras, Rion, Greece
| | | |
Collapse
|
6
|
Nguyen TXD, Kuo CW, Peng CW, Liu HL, Chang MY, Hsieh TH. Transcranial burst electrical stimulation contributes to neuromodulatory effects in the rat motor cortex. Front Neurosci 2023; 17:1303014. [PMID: 38146544 PMCID: PMC10749301 DOI: 10.3389/fnins.2023.1303014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 11/24/2023] [Indexed: 12/27/2023] Open
Abstract
Background and objective Transcranial Burst Electrical Stimulation (tBES) is an innovative non-invasive brain stimulation technique that combines direct current (DC) and theta burst stimulation (TBS) for brain neuromodulation. It has been suggested that the tBES protocol may efficiently induce neuroplasticity. However, few studies have systematically tested neuromodulatory effects and underlying neurophysiological mechanisms by manipulating the polarity of DC and TBS patterns. This study aimed to develop the platform and assess neuromodulatory effects and neuronal activity changes following tBES. Methods Five groups of rats were exposed to anodal DC combined with intermittent TBS (tBES+), cathodal DC combined with continuous TBS (tBES-), anodal and cathodal transcranial direct current stimulation (tDCS+ and tDCS-), and sham groups. The neuromodulatory effects of each stimulation on motor cortical excitability were analyzed by motor-evoked potentials (MEPs) changes. We also investigated the effects of tBES on both excitatory and inhibitory neural biomarkers. We specifically examined c-Fos and glutamic acid decarboxylase (GAD-65) using immunohistochemistry staining techniques. Additionally, we evaluated the safety of tBES by analyzing glial fibrillary acidic protein (GFAP) expression. Results Our findings demonstrated significant impacts of tBES on motor cortical excitability up to 30 min post-stimulation. Specifically, MEPs significantly increased after tBES (+) compared to pre-stimulation (p = 0.026) and sham condition (p = 0.025). Conversely, tBES (-) led to a notable decrease in MEPs relative to baseline (p = 0.04) and sham condition (p = 0.048). Although tBES showed a more favorable neuromodulatory effect than tDCS, statistical analysis revealed no significant differences between these two groups (p > 0.05). Additionally, tBES (+) exhibited a significant activation of excitatory neurons, indicated by increased c-Fos expression (p < 0.05), and a reduction in GAD-65 density (p < 0.05). tBES (-) promoted GAD-65 expression (p < 0.05) while inhibiting c-Fos activation (p < 0.05), suggesting the involvement of cortical inhibition with tBES (-). The expression of GFAP showed no significant difference between tBES and sham conditions (p > 0.05), indicating that tBES did not induce neural injury in the stimulated regions. Conclusion Our study indicates that tBES effectively modulates motor cortical excitability. This research significantly contributes to a better understanding of the neuromodulatory effects of tBES, and could provide valuable evidence for its potential clinical applications in treating neurological disorders.
Collapse
Affiliation(s)
- Thi Xuan Dieu Nguyen
- School of Physical Therapy and Graduate Institute of Rehabilitation Science, Chang Gung University, Taoyuan, Taiwan
| | - Chi-Wei Kuo
- School of Physical Therapy and Graduate Institute of Rehabilitation Science, Chang Gung University, Taoyuan, Taiwan
| | - Chih-Wei Peng
- School of Biomedical Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei, Taiwan
| | - Hao-Li Liu
- Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan
| | - Ming-Yuan Chang
- Division of Neurosurgery, Department of Surgery, Min-Sheng General Hospital, Taoyuan, Taiwan
| | - Tsung-Hsun Hsieh
- School of Physical Therapy and Graduate Institute of Rehabilitation Science, Chang Gung University, Taoyuan, Taiwan
- Healthy Aging Research Center, Chang Gung University, Taoyuan, Taiwan
- Neuroscience Research Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| |
Collapse
|
7
|
Sharifi M, Oryan S, Komaki A, Barkley V, Sarihi A, Mirnajafi-Zadeh J. Comparing the synaptic potentiation in schaffer collateral-CA1 synapses in dorsal and intermediate regions of the hippocampus in normal and kindled rats. IBRO Neurosci Rep 2023; 15:252-261. [PMID: 37841086 PMCID: PMC10570600 DOI: 10.1016/j.ibneur.2023.09.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 09/26/2023] [Accepted: 09/30/2023] [Indexed: 10/17/2023] Open
Abstract
There is growing evidence that the hippocampus comprises diverse neural circuits that exhibit longitudinal variation in their properties, however, the intermediate region of the hippocampus has received comparatively little attention. Therefore, this study was designed to compared short- and long-term synaptic plasticity between the dorsal and intermediate regions of the hippocampus in normal and PTZ-kindled rats. Short-term plasticity was assessed by measuring the ratio of field excitatory postsynaptic potentials' (fEPSPs) slope in response to paired-pulse stimulation at three different inter-pulse intervals (20, 80, and 160 ms), while long-term plasticity was assessed using primed burst stimulation (PBS). The results showed that the basal synaptic strength differed between the dorsal and intermediate regions of the hippocampus in both control and kindled rats. In the control group, paired-pulse stimulation of Schaffer collaterals resulted in a significantly lower fEPSP slope in the intermediate part of the hippocampus compared to the dorsal region. Additionally, the magnitude of long-term potentiation (LTP) was significantly lower in the intermediate part of the hippocampus compared to the dorsal region. In PTZ-kindled rats, both short-term facilitation and long-term potentiation were impaired in both regions of the hippocampus. Interestingly, there was no significant difference in synaptic plasticity between the dorsal and intermediate regions in PTZ-kindled rats, despite impairments in both regions. This suggests that seizures eliminate the regional difference between the dorsal and intermediate parts of the hippocampus, resulting in similar electrophysiological activity in both regions in kindled animals. Future studies should consider this when investigating the responses of the dorsal and intermediate regions of the hippocampus following PTZ kindling.
Collapse
Affiliation(s)
- Maryam Sharifi
- Department of Animal Biology, Faculty of Biological Science, Kharazmi University, Tehran, Iran
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Shahrbanoo Oryan
- Department of Animal Biology, Faculty of Biological Science, Kharazmi University, Tehran, Iran
| | - Alireza Komaki
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
- Department of Neuroscience, School of Sciences and Advanced Technology in Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Victoria Barkley
- Krembil Research Institute, University Health Network, Toronto, Canada
| | - Abdolrahman Sarihi
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
- Department of Neuroscience, School of Sciences and Advanced Technology in Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Javad Mirnajafi-Zadeh
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| |
Collapse
|
8
|
Leontiadis LJ, Trompoukis G, Felemegkas P, Tsotsokou G, Miliou A, Papatheodoropoulos C. Increased Inhibition May Contribute to Maintaining Normal Network Function in the Ventral Hippocampus of a Fmr1-Targeted Transgenic Rat Model of Fragile X Syndrome. Brain Sci 2023; 13:1598. [PMID: 38002556 PMCID: PMC10669536 DOI: 10.3390/brainsci13111598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 11/10/2023] [Accepted: 11/13/2023] [Indexed: 11/26/2023] Open
Abstract
A common neurobiological mechanism in several neurodevelopmental disorders, including fragile X syndrome (FXS), is alterations in the balance between excitation and inhibition in the brain. It is thought that in the hippocampus, as in other brain regions, FXS is associated with increased excitability and reduced inhibition. However, it is still not known whether these changes apply to both the dorsal and ventral hippocampus, which appear to be differently involved in neurodegenerative disorders. Using a Fmr1 knock-out (KO) rat model of FXS, we found increased neuronal excitability in both the dorsal and ventral KO hippocampus and increased excitatory synaptic transmission in the dorsal hippocampus. Interestingly, synaptic inhibition is significantly increased in the ventral but not the dorsal KO hippocampus. Furthermore, the ventral KO hippocampus displays increased expression of the α1GABAA receptor subtype and a remarkably reduced rate of epileptiform discharges induced by magnesium-free medium. In contrast, the dorsal KO hippocampus displays an increased rate of epileptiform discharges and similar expression of α1GABAA receptors compared with the dorsal WT hippocampus. Blockade of α5GABAA receptors by L-655,708 did not affect epileptiform discharges in any genotype or hippocampal segment, and the expression of α5GABAA receptors did not differ between WT and KO hippocampus. These results suggest that the increased excitability of the dorsal KO hippocampus contributes to its heightened tendency to epileptiform discharges, while the increased phasic inhibition in the Fmr1-KO ventral hippocampus may represent a homeostatic mechanism that compensates for the increased excitability reducing its vulnerability to epileptic activity.
Collapse
Affiliation(s)
| | | | | | | | | | - Costas Papatheodoropoulos
- Laboratory of Neurophysiology, Department of Medicine, University of Patras, 26504 Rion, Greece; (L.J.L.); (G.T. (George Trompoukis)); (P.F.); (G.T. (Giota Tsotsokou)); (A.M.)
| |
Collapse
|
9
|
Dahlmanns M, Valero-Aracama MJ, Dahlmanns JK, Zheng F, Alzheimer C. Tonic activin signaling shapes cellular and synaptic properties of CA1 neurons mainly in dorsal hippocampus. iScience 2023; 26:108001. [PMID: 37829200 PMCID: PMC10565779 DOI: 10.1016/j.isci.2023.108001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 08/07/2023] [Accepted: 09/18/2023] [Indexed: 10/14/2023] Open
Abstract
Dorsal and ventral hippocampus serve different functions in cognition and affective behavior, but the underpinnings of this diversity at the cellular and synaptic level are not well understood. We found that the basal level of activin A, a member of the TGF-β family, which regulates hippocampal circuits in a behaviorally relevant fashion, is much higher in dorsal than in ventral hippocampus. Using transgenic mice with a forebrain-specific disruption of activin receptor signaling, we identified the pronounced dorsal-ventral gradient of activin A as a major factor determining the distinct neurophysiologic signatures of dorsal and ventral hippocampus, ranging from pyramidal cell firing, tuning of frequency-dependent synaptic facilitation, to long-term potentiation (LTP), long-term depression (LTD), and de-potentiation. Thus, the strong activin A tone in dorsal hippocampus appears crucial to establish cellular and synaptic phenotypes that are tailored specifically to the respective network operations in dorsal and ventral hippocampus.
Collapse
Affiliation(s)
- Marc Dahlmanns
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Maria Jesus Valero-Aracama
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Jana Katharina Dahlmanns
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Fang Zheng
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Christian Alzheimer
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| |
Collapse
|
10
|
Chen S, He X, Wei X, Huang J, Zhang J. After-effects of repetitive transcranial magnetic stimulation with parameter dependence on long-term potentiation-like plasticity and object recognition memory in rats. Front Neurosci 2023; 17:1144480. [PMID: 37795181 PMCID: PMC10546014 DOI: 10.3389/fnins.2023.1144480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Accepted: 07/07/2023] [Indexed: 10/06/2023] Open
Abstract
Objective To investigate the after-effects of 25-Hz repetitive transcranial magnetic stimulation (rTMS) at 60, 100, and 120% resting motor threshold (rMT) on long-term potentiation (LTP) in the rat hippocampus, to clarify the intensity dependence of rTMS, and to determine whether it simultaneously affects learning and memory ability. Methods Five rats were randomly selected from 70 male Wistar rats, and evoked rMT potentials were recorded in response to magnetic stimulation. The remaining 65 rats were randomly assigned to five groups (n = 13), including sham rTMS, 1 Hz 100% rMT, and 25 Hz rTMS groups with 3 subgroups of 60% rMT, 100% rMT, and 120% rMT. Five rats in each group were anesthetized and induced by a priming TMS-test design for population spike (PS) response of the perforant path-dentate gyrus in the hippocampus; the remaining eight rats in each group were evaluated for object recognition memory in the novel object recognition (NOR) task after the different rTMS protocols. Results Forty-five percent (approximately 1.03 T) of the magnetic stimulator output was confirmed as rMT in the biceps femoris muscle. The PS ratio was ranked as follows: 25 Hz 100% rMT (267.78 ± 25.71%) > sham rTMS (182 ± 9.4%) >1 Hz 100% rMT (102.69 ± 6.64%) > 25 Hz 120% rMT (98 ± 11.3%) > 25 Hz 60% rMT (36 ± 8.5%). Significant differences were observed between the groups, except for the difference between the 25 Hz 120% rMT and the 1 Hz 100% rMT groups (p = 0.446). LTP was successfully induced over the 60-min recording period only in the sham rTMS and 25 Hz 100% rMT groups. Moreover, these two groups spent more time exploring a novel object than a familiar object during the NOR task (p < 0.001), suggesting long-term recognition memory retention. In the between-group analysis of the discrimination index, the following ranking was observed: 25 Hz 100% rMT (0.812 ± 0.158) > sham rTMS (0.653 ± 0.111) > 25 Hz 120% rMT (0.583 ± 0.216) >1 Hz 100% rMT (0.581 ± 0.145) > 25 Hz 60% rMT (0.532 ± 0.220). Conclusion The after-effect of 25-Hz rTMS was dependent on stimulus intensity and provided an inverted (V-shaped) bidirectional modulation on hippocampal plasticity that involved two forms of metaplasticity. Furthermore, the effects on the recognition memory ability were positively correlated with those on LTP induction in the hippocampus in vivo.
Collapse
Affiliation(s)
- Shanjia Chen
- The First Affiliated Hospital of Xiamen University, Xiamen, China
- Laboratory Neuropathology, Institute Medicine College, Xiamen University, Xiamen, China
| | - Xiaokuo He
- Fifth Hospital of Xiamen, Xiamen, China
- Xiangyang Central Hospital, Affiliated Hospital of Hubei University of Arts and Science, Xiangyang, Hubei, China
- The Graduate School of Fujian Medical University, Fuzhou, Fujian, China
| | - XinChen Wei
- The Graduate School of Fujian Medical University, Fuzhou, Fujian, China
| | - Jiyi Huang
- The First Affiliated Hospital of Xiamen University, Xiamen, China
- Fifth Hospital of Xiamen, Xiamen, China
| | - Jie Zhang
- Laboratory Neuropathology, Institute Medicine College, Xiamen University, Xiamen, China
| |
Collapse
|
11
|
Cope EC, Wang SH, Waters RC, Gore IR, Vasquez B, Laham BJ, Gould E. Activation of the CA2-ventral CA1 pathway reverses social discrimination dysfunction in Shank3B knockout mice. Nat Commun 2023; 14:1750. [PMID: 36991001 PMCID: PMC10060401 DOI: 10.1038/s41467-023-37248-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 03/07/2023] [Indexed: 03/30/2023] Open
Abstract
Mutation or deletion of the SHANK3 gene, which encodes a synaptic scaffolding protein, is linked to autism spectrum disorder and Phelan-McDermid syndrome, conditions associated with social memory impairments. Shank3B knockout mice also exhibit social memory deficits. The CA2 region of the hippocampus integrates numerous inputs and sends a major output to the ventral CA1 (vCA1). Despite finding few differences in excitatory afferents to the CA2 in Shank3B knockout mice, we found that activation of CA2 neurons as well as the CA2-vCA1 pathway restored social recognition function to wildtype levels. vCA1 neuronal oscillations have been linked to social memory, but we observed no differences in these measures between wildtype and Shank3B knockout mice. However, activation of the CA2 enhanced vCA1 theta power in Shank3B knockout mice, concurrent with behavioral improvements. These findings suggest that stimulating adult circuitry in a mouse model with neurodevelopmental impairments can invoke latent social memory function.
Collapse
Affiliation(s)
- Elise C Cope
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, 08544, USA
- Department of Neuroscience, University of Virginia School of Medicine, Charlottesville, VA, 22908, USA
| | - Samantha H Wang
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, 08544, USA
| | - Renée C Waters
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, 08544, USA
| | - Isha R Gore
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, 08544, USA
| | - Betsy Vasquez
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, 08544, USA
| | - Blake J Laham
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, 08544, USA
| | - Elizabeth Gould
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, 08544, USA.
| |
Collapse
|
12
|
Launay A, Nebie O, Vijaya Shankara J, Lebouvier T, Buée L, Faivre E, Blum D. The role of adenosine A 2A receptors in Alzheimer's disease and tauopathies. Neuropharmacology 2023; 226:109379. [PMID: 36572177 DOI: 10.1016/j.neuropharm.2022.109379] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 12/12/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022]
Abstract
Adenosine signals through four distinct G protein-coupled receptors that are located at various synapses, cell types and brain areas. Through them, adenosine regulates neuromodulation, neuronal signaling, learning and cognition as well as the sleep-wake cycle, all strongly impacted in neurogenerative disorders, among which Alzheimer's Disease (AD). AD is a complex form of cognitive deficits characterized by two pathological hallmarks: extracellular deposits of aggregated β-amyloid peptides and intraneuronal fibrillar aggregates of hyper- and abnormally phosphorylated Tau proteins. Both lesions contribute to the early dysfunction and loss of synapses which are strongly associated to the development of cognitive decline in AD patients. The present review focuses on the pathophysiological impact of the A2ARs dysregulation observed in cognitive area from AD patients. We are reviewing not only evidence of the cellular changes in A2AR levels in pathological conditions but also describe what is currently known about their consequences in term of synaptic plasticity, neuro-glial miscommunication and memory abilities. We finally summarize the proof-of-concept studies that support A2AR as credible targets and the clinical interest to repurpose adenosine drugs for the treatment of AD and related disorders. This article is part of the Special Issue on "Purinergic Signaling: 50 years".
Collapse
Affiliation(s)
- Agathe Launay
- Univ. Lille, Inserm, CHU Lille, UMR-S1172 LilNCog - Lille Neuroscience & Cognition, F-59000, Lille, France; Alzheimer and Tauopathies, LabEx DISTALZ, France
| | - Ouada Nebie
- Univ. Lille, Inserm, CHU Lille, UMR-S1172 LilNCog - Lille Neuroscience & Cognition, F-59000, Lille, France; Alzheimer and Tauopathies, LabEx DISTALZ, France
| | - Jhenkruthi Vijaya Shankara
- Univ. Lille, Inserm, CHU Lille, UMR-S1172 LilNCog - Lille Neuroscience & Cognition, F-59000, Lille, France; Alzheimer and Tauopathies, LabEx DISTALZ, France
| | - Thibaud Lebouvier
- Univ. Lille, Inserm, CHU Lille, UMR-S1172 LilNCog - Lille Neuroscience & Cognition, F-59000, Lille, France; Alzheimer and Tauopathies, LabEx DISTALZ, France; CHU Lille, Memory Clinic, Lille, France
| | - Luc Buée
- Univ. Lille, Inserm, CHU Lille, UMR-S1172 LilNCog - Lille Neuroscience & Cognition, F-59000, Lille, France; Alzheimer and Tauopathies, LabEx DISTALZ, France
| | - Emilie Faivre
- Univ. Lille, Inserm, CHU Lille, UMR-S1172 LilNCog - Lille Neuroscience & Cognition, F-59000, Lille, France; Alzheimer and Tauopathies, LabEx DISTALZ, France
| | - David Blum
- Univ. Lille, Inserm, CHU Lille, UMR-S1172 LilNCog - Lille Neuroscience & Cognition, F-59000, Lille, France; Alzheimer and Tauopathies, LabEx DISTALZ, France.
| |
Collapse
|
13
|
Anvari S, Foolad F, Javan M, Mirnajafi-Zadeh J, Fathollahi Y. A distinct impact of repeated morphine exposure on synaptic plasticity at Schaffer collateral-CA1, temporoammonic-CA1, and perforant pathway-dentate gyrus synapses along the longitudinal axis of the hippocampus. Hippocampus 2023; 33:47-62. [PMID: 36514833 DOI: 10.1002/hipo.23488] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 11/23/2022] [Accepted: 11/28/2022] [Indexed: 12/15/2022]
Abstract
We aimed to study how morphine affects synaptic transmission in the dentate gyrus and CA1 regions along the hippocampal long axis. For this, recording and measuring of field excitatory postsynaptic potentials (fEPSPs) were utilized to test the effects of repeated morphine exposure on paired-pulse evoked responses and long-term potentiation (LTP) at Schaffer collateral-CA1 (Sch-CA1), temporoammonic-CA1 (TA-CA1) and perforant pathway-dentate gyrus (PP-DG) synapses in transverse slices from the dorsal (DH), intermediate (IH), and ventral (VH) hippocampus in adult male rats. After repeated morphine exposure, the expression of opioid receptors and the α1 and α5 GABAA subunits were also examined. We found that repeated morphine exposure blunt the difference between the DH and the VH in their basal levels of synaptic transmission at Sch-CA1 synapses that were seen in the control groups. Significant paired-pulse facilitation of excitatory synaptic transmission was observed at Sch-CA1 synapses in slices taken from all three hippocampal segments as well as at PP-DG synapses in slices taken from the VH segment in the morphine-treated groups as compared to the control groups. Interestingly, significant paired-pulse inhibition of excitatory synaptic transmission was observed at TA-CA1 synapses in the DH slices from the morphine-treated group as compared to the control group. While primed-burst stimulation (a protocol reflecting normal neuronal firing) induced a robust LTP in hippocampal subfields in all control groups, resulting in a decaying LTP at TA-CA1 synapses in the VH slices and at PP-DG synapses in both the IH and VH slices taken from the morphine-treated rats. In the DH of morphine-treated rats, we found increased levels of the mRNAs encoding the α1 and α5 GABAA subunits as compared to the control group. Taken together, these findings suggest the potential mechanisms through which repeated morphine exposure causes differential changes in circuit excitability and synaptic plasticity in the dentate gyrus and CA1 regions along the hippocampal long axis.
Collapse
Affiliation(s)
- Sohrab Anvari
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Forough Foolad
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Mohammad Javan
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Javad Mirnajafi-Zadeh
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Yaghoub Fathollahi
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| |
Collapse
|
14
|
Besing GLK, St. John EK, Potesta CV, Gallagher MJ, Zhou C. Artificial sleep-like up/down-states induce synaptic plasticity in cortical neurons from mouse brain slices. Front Cell Neurosci 2022; 16:948327. [PMID: 36313618 PMCID: PMC9615418 DOI: 10.3389/fncel.2022.948327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 08/09/2022] [Indexed: 02/02/2023] Open
Abstract
During non-rapid eye movement (NREM) sleep, cortical neuron activity alternates between a depolarized (firing, up-state) and a hyperpolarized state (down-state) coinciding with delta electroencephalogram (EEG) slow-wave oscillation (SWO, 0. 5-4 Hz) in vivo. Recently, we have found that artificial sleep-like up/down-states can potentiate synaptic strength in layer V cortical neurons ex vivo. Using mouse coronal brain slices, whole cell voltage-clamp recordings were made from layer V cortical pyramidal neurons to record spontaneous excitatory synaptic currents (sEPSCs) and inhibitory synaptic currents (sIPSCs). Artificial sleep-like up/down-states (as SWOs, 0.5 Hz, 10 min, current clamp mode) were induced by injecting sinusoidal currents into layer V cortical neurons. Baseline pre-SWO recordings were recorded for 5 min and post-SWO recordings for at least 25-30 min. Compared to pre-SWO sEPSCs or sIPSCs, post-SWO sEPSCs or sIPSCs in layer V cortical neurons exhibited significantly larger amplitudes and a higher frequency for 30 min. This finding suggests that both sEPSCs and sIPSCs could be potentiated in layer V cortical neurons by the low-level activity of SWOs, and sEPSCs and sIPSCs maintained a balance in layer V cortical neurons during pre- and post-SWO periods. Overall, this study presents an ex vivo method to show SWO's ability to induce synaptic plasticity in layer V cortical neurons, which may underlie sleep-related synaptic potentiation for sleep-related memory consolidation in vivo.
Collapse
Affiliation(s)
- Gai-Linn Kay Besing
- Departments of Neurology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Emily Kate St. John
- Departments of Neurology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Cobie Victoria Potesta
- Departments of Neurology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Martin J. Gallagher
- Departments of Neurology, Vanderbilt University Medical Center, Nashville, TN, United States,Neuroscience Graduate Program, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Chengwen Zhou
- Departments of Neurology, Vanderbilt University Medical Center, Nashville, TN, United States,Neuroscience Graduate Program, Vanderbilt University Medical Center, Nashville, TN, United States,*Correspondence: Chengwen Zhou
| |
Collapse
|
15
|
Unravelling biological roles and mechanisms of GABA BR on addiction and depression through mood and memory disorders. Biomed Pharmacother 2022; 155:113700. [PMID: 36152411 DOI: 10.1016/j.biopha.2022.113700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/08/2022] [Accepted: 09/13/2022] [Indexed: 11/23/2022] Open
Abstract
The metabotropic γ-aminobutyric acid type B receptor (GABABR) remains a hotspot in the recent research area. Being an idiosyncratic G-protein coupled receptor family member, the GABABR manifests adaptively tailored functionality under multifarious modulations by a constellation of agents, pointing to cross-talk between receptors and effectors that converge on the domains of mood and memory. This review systematically summarizes the latest achievements in signal transduction mechanisms of the GABABR-effector-regulator complex and probes how the up-and down-regulation of membrane-delimited GABABRs are associated with manifold intrinsic and extrinsic agents in synaptic strength and plasticity. Neuropsychiatric conditions depression and addiction share the similar pathophysiology of synapse inadaptability underlying negative mood-related processes, memory formations, and impairments. In the attempt to emphasize all convergent discoveries, we hope the insights gained on the GABABR system mechanisms of action are conducive to designing more therapeutic candidates so as to refine the prognosis rate of diseases and minimize side effects.
Collapse
|
16
|
Recognition Memory Induces Natural LTP-like Hippocampal Synaptic Excitation and Inhibition. Int J Mol Sci 2022; 23:ijms231810806. [PMID: 36142727 PMCID: PMC9501019 DOI: 10.3390/ijms231810806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 09/09/2022] [Accepted: 09/12/2022] [Indexed: 11/29/2022] Open
Abstract
Synaptic plasticity is a cellular process involved in learning and memory by which specific patterns of neural activity adapt the synaptic strength and efficacy of the synaptic transmission. Its induction is governed by fine tuning between excitatory/inhibitory synaptic transmission. In experimental conditions, synaptic plasticity can be artificially evoked at hippocampal CA1 pyramidal neurons by repeated stimulation of Schaffer collaterals. However, long-lasting synaptic modifications studies during memory formation in physiological conditions in freely moving animals are very scarce. Here, to study synaptic plasticity phenomena during recognition memory in the dorsal hippocampus, field postsynaptic potentials (fPSPs) evoked at the CA3–CA1 synapse were recorded in freely moving mice during object-recognition task performance. Paired pulse stimuli were applied to Schaffer collaterals at the moment that the animal explored a new or a familiar object along different phases of the test. Stimulation evoked a complex synaptic response composed of an ionotropic excitatory glutamatergic fEPSP, followed by two inhibitory responses, an ionotropic, GABAA-mediated fIPSP and a metabotropic, G-protein-gated inwardly rectifying potassium (GirK) channel-mediated fIPSP. Our data showed the induction of LTP-like enhancements for both the glutamatergic and GirK-dependent components of the dorsal hippocampal CA3–CA1 synapse during the exploration of novel but not familiar objects. These results support the contention that synaptic plasticity processes that underlie hippocampal-dependent memory are sustained by fine tuning mechanisms that control excitatory and inhibitory neurotransmission balance.
Collapse
|
17
|
A. Samara M, Oikonomou GD, Trompoukis G, Madarou G, Adamopoulou M, Papatheodoropoulos C. Septotemporal variation in modulation of synaptic transmission, paired-pulse ratio and frequency facilitation/depression by adenosine and GABA B receptors in the rat hippocampus. Brain Neurosci Adv 2022; 6:23982128221106315. [PMID: 35782711 PMCID: PMC9240614 DOI: 10.1177/23982128221106315] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Accepted: 05/19/2022] [Indexed: 11/26/2022] Open
Abstract
Short-term synaptic plasticity represents a fundamental mechanism in
neural information processing and is regulated by neuromodulators.
Here, using field recordings from the CA1 region of adult rat
hippocampal slices, we show that excitatory synaptic transmission is
suppressed by strong but not moderate activation of adenosine
A1 receptors by
2-Chloro-N6-cyclopentyladenosine (CCPA) more in the dorsal
than the ventral hippocampus; in contrast, both mild and strong
activation of GABAB receptors by baclofen (1 μM, 10 μM)
suppress synaptic transmission more in the ventral than the dorsal
hippocampus. Using a 10-pulse stimulation train of variable frequency,
we found that CCPA modulates short-term synaptic plasticity
independently of the suppression of synaptic transmission in both
segments of the hippocampus and at stimulation frequencies greater
than 10 Hz. However, specifically regarding the paired-pulse ratio
(PPR) and frequency facilitation/depression (FF/D) we found
significant drug action before but not after adjusting conditioning
responses to control levels. Activation of GABABRs by
baclofen suppressed synaptic transmission more in the ventral than the
dorsal hippocampus. Furthermore, relatively high (10 μM) but not low
(1 μM) baclofen concentration enhanced both PPR and FF in both
hippocampal segments at stimulation frequencies greater than 1 Hz,
independently of the suppression of synaptic transmission by baclofen.
These results show that A1Rs and GABABRs control
synaptic transmission more effectively in the dorsal and the ventral
hippocampus, respectively, and suggest that these receptors modulate
PPR and FF/D at different frequency bands of afferent input, in both
segments of the hippocampus.
Collapse
Affiliation(s)
- Maria A. Samara
- Laboratory of Neurophysiology, Department of Medicine, University of Patras, Rion, Greece
| | - George D. Oikonomou
- Laboratory of Neurophysiology, Department of Medicine, University of Patras, Rion, Greece
| | - George Trompoukis
- Laboratory of Neurophysiology, Department of Medicine, University of Patras, Rion, Greece
| | - Georgia Madarou
- Laboratory of Neurophysiology, Department of Medicine, University of Patras, Rion, Greece
| | - Maria Adamopoulou
- Laboratory of Neurophysiology, Department of Medicine, University of Patras, Rion, Greece
| | | |
Collapse
|
18
|
Zhang HL, Zhao B, Han W, Sun YB, Yang P, Chen Y, Ni D, Zhang J, Yin DM. Acetylation of calmodulin regulates synaptic plasticity and fear learning. J Biol Chem 2021; 297:101034. [PMID: 34339735 PMCID: PMC8383114 DOI: 10.1016/j.jbc.2021.101034] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 07/20/2021] [Accepted: 07/29/2021] [Indexed: 11/26/2022] Open
Abstract
Synaptic plasticity is critical for brain function, including learning and memory. It is regulated by gene transcription and protein synthesis as well as posttranslational modifications at synapses. Although protein acetylation has been shown to be involved in the regulation of synaptic plasticity, this was mainly for histone protein acetylation. To investigate whether acetylation of nonhistone proteins is important for synaptic plasticity, we analyzed mouse brain acetylome and found that calmodulin (CaM), a ubiquitous Ca2+ sensor, was acetylated on three lysine residues, which were conserved across species. NMDA receptor-dependent long-term potentiation (LTP) is considered the most compelling form of synaptic plasticity. During LTP induction, activation of NMDA receptor triggers Ca2+ influx, and the Ca2+ binds with CaM and activates calcium/calmodulin-dependent protein kinase IIα (CaMKIIα), which is essential for LTP induction. By using home-generated and site-specific antibodies against acetylated CaM, we show that CaM acetylation is upregulated by neural activities in an NMDA receptor-dependent manner. Moreover, mutation of acetyllysines in CaM1 proteins disrupts synaptic plasticity and fear learning in a mouse model. We further demonstrate that acetylation of CaM reduces the binding free energy and increases the binding affinity toward CaMKIIα, a protein kinase pivotal to synaptic plasticity and learning. Taken together, our results demonstrate importance of CaM acetylation in regulating synaptic plasticity and learning.
Collapse
Affiliation(s)
- Hai-Long Zhang
- Key Laboratory of Brain Functional Genomics, Ministry of Education and Shanghai, School of Life Science, East China Normal University, Shanghai, China; Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Bing Zhao
- Key Laboratory of Brain Functional Genomics, Ministry of Education and Shanghai, School of Life Science, East China Normal University, Shanghai, China
| | - Wei Han
- Key Laboratory of Brain Functional Genomics, Ministry of Education and Shanghai, School of Life Science, East China Normal University, Shanghai, China
| | - Yi-Bei Sun
- Key Laboratory of Brain Functional Genomics, Ministry of Education and Shanghai, School of Life Science, East China Normal University, Shanghai, China
| | - Pin Yang
- Key Laboratory of Brain Functional Genomics, Ministry of Education and Shanghai, School of Life Science, East China Normal University, Shanghai, China
| | - Yongjun Chen
- Medical College of Acu-Moxi and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Duan Ni
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Department of Pharmacy, Clinical and Fundamental Research Center, Renji Hospital, Shanghai Jiao-Tong University School of Medicine (SJTU-SM), Shanghai, China
| | - Jian Zhang
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Department of Pharmacy, Clinical and Fundamental Research Center, Renji Hospital, Shanghai Jiao-Tong University School of Medicine (SJTU-SM), Shanghai, China
| | - Dong-Min Yin
- Key Laboratory of Brain Functional Genomics, Ministry of Education and Shanghai, School of Life Science, East China Normal University, Shanghai, China.
| |
Collapse
|
19
|
Zhang HL, Zhao B, Yang P, Du YQ, Han W, Xu J, Yin DM. Steroid Receptor Coactivator 3 Regulates Synaptic Plasticity and Hippocampus-dependent Memory. Neurosci Bull 2021; 37:1645-1657. [PMID: 34228315 PMCID: PMC8643392 DOI: 10.1007/s12264-021-00741-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 02/27/2021] [Indexed: 11/28/2022] Open
Abstract
Steroid hormones play important roles in brain development and function. The signaling of steroid hormones depends on the interaction between steroid receptors and their coactivators. Although the function of steroid receptor coactivators has been extensively studied in other tissues, their functions in the central nervous system are less well investigated. In this study, we addressed the function of steroid receptor coactivator 3 (SRC3) - a member of the p160 SRC protein family that is expressed predominantly in the hippocampus. While hippocampal development was not altered in Src3+/- mice, hippocampus-dependent functions such as short-term memory and spatial memory were impaired. We further demonstrated that the deficient learning and memory in Src3+/- mice was strongly associated with the impairment of long-term potentiation (LTP) at Schaffer Collateral-CA1 synapses. Mechanistic studies indicated that Src3+/- mutation altered the composition of N-methyl-D-aspartate receptor subunits in the postsynaptic densities of hippocampal neurons. Finally, we showed that SRC3 regulated synaptic plasticity and learning mainly dependent on its lysine acetyltransferase activity. Taken together, these results reveal previously unknown functions of SRC3 in the hippocampus and thus may provide insight into how steroid hormones regulate brain function.
Collapse
Affiliation(s)
- Hai-Long Zhang
- Key Laboratory of Brain Functional Genomics, Ministry of Education and Shanghai, School of Life Science, East China Normal University, Shanghai, 200062, China
| | - Bing Zhao
- MOE Frontiers Center for Brain Science, Institute for Translational Brain Research, Fudan University, Shanghai, 200032, China
| | - Pin Yang
- Key Laboratory of Brain Functional Genomics, Ministry of Education and Shanghai, School of Life Science, East China Normal University, Shanghai, 200062, China
| | - Yin-Quan Du
- Key Laboratory of Brain Functional Genomics, Ministry of Education and Shanghai, School of Life Science, East China Normal University, Shanghai, 200062, China
| | - Wei Han
- Key Laboratory of Brain Functional Genomics, Ministry of Education and Shanghai, School of Life Science, East China Normal University, Shanghai, 200062, China
| | - Jianming Xu
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Dong-Min Yin
- Key Laboratory of Brain Functional Genomics, Ministry of Education and Shanghai, School of Life Science, East China Normal University, Shanghai, 200062, China.
| |
Collapse
|
20
|
Briggs SB, Hannapel R, Ramesh J, Parent MB. Inhibiting ventral hippocampal NMDA receptors and Arc increases energy intake in male rats. ACTA ACUST UNITED AC 2021; 28:187-194. [PMID: 34011515 PMCID: PMC8139633 DOI: 10.1101/lm.053215.120] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 04/02/2021] [Indexed: 11/24/2022]
Abstract
Research into the neural mechanisms that underlie higher-order cognitive control of eating behavior suggests that ventral hippocampal (vHC) neurons, which are critical for emotional memory, also inhibit energy intake. We showed previously that optogenetically inhibiting vHC glutamatergic neurons during the early postprandial period, when the memory of the meal would be undergoing consolidation, caused rats to eat their next meal sooner and to eat more during that next meal when the neurons were no longer inhibited. The present research determined whether manipulations known to interfere with synaptic plasticity and memory when given pretraining would increase energy intake when given prior to ingestion. Specifically, we tested the effects of blocking vHC glutamatergic N-methyl-D-aspartate receptors (NMDARs) and activity-regulated cytoskeleton-associated protein (Arc) on sucrose ingestion. The results showed that male rats consumed a larger sucrose meal on days when they were given vHC infusions of the NMDAR antagonist APV or Arc antisense oligodeoxynucleotides than on days when they were given control infusions. The rats did not accommodate for that increase by delaying the onset of their next sucrose meal (i.e., decreased satiety ratio) or by eating less during the next meal. These data suggest that vHC NMDARs and Arc limit meal size and inhibit meal initiation.
Collapse
Affiliation(s)
- Sherri B Briggs
- Neuroscience Institute, Georgia State University, Atlanta, Georgia 30303, USA
| | - Reilly Hannapel
- Neuroscience Institute, Georgia State University, Atlanta, Georgia 30303, USA
| | - Janavi Ramesh
- Neuroscience Institute, Georgia State University, Atlanta, Georgia 30303, USA
| | - Marise B Parent
- Neuroscience Institute, Georgia State University, Atlanta, Georgia 30303, USA.,Department of Psychology, Georgia State University, Atlanta, Georgia 30303, USA
| |
Collapse
|
21
|
Albrecht A, Redavide E, Regev-Tsur S, Stork O, Richter-Levin G. Hippocampal GABAergic interneurons and their co-localized neuropeptides in stress vulnerability and resilience. Neurosci Biobehav Rev 2020; 122:229-244. [PMID: 33188820 DOI: 10.1016/j.neubiorev.2020.11.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 10/05/2020] [Accepted: 11/01/2020] [Indexed: 12/13/2022]
Abstract
Studies in humans and rodents suggest a critical role for the hippocampal formation in cognition and emotion, but also in the adaptation to stressful events. Successful stress adaptation promotes resilience, while its failure may lead to stress-induced psychopathologies such as depression and anxiety disorders. Hippocampal architecture and physiology is shaped by its strong control of activity via diverse classes of inhibitory interneurons that express typical calcium binding proteins and neuropeptides. Celltype-specific opto- and chemogenetic intervention strategies that take advantage of these biochemical markers have bolstered our understanding of the distinct role of different interneurons in anxiety, fear and stress adaptation. Moreover, some of the signature proteins of GABAergic interneurons have a potent impact on emotion and cognition on their own, making them attractive targets for interventions. In particular, neuropeptide Y is a promising endogenous agent for mediating resilience against severe stress. In this review, we evaluate the role of the major types of interneurons across hippocampal subregions in the adaptation to chronic and acute stress and to emotional memory formation.
Collapse
Affiliation(s)
- Anne Albrecht
- Institute of Anatomy, Otto-von-Guericke-University Magdeburg, Leipziger Str. 44, 39120 Magdeburg, Germany; Center for Behavioral Brain Science, Universitätsplatz 2, 39106 Magdeburg, Germany.
| | - Elisa Redavide
- Institute of Anatomy, Otto-von-Guericke-University Magdeburg, Leipziger Str. 44, 39120 Magdeburg, Germany; Center for Behavioral Brain Science, Universitätsplatz 2, 39106 Magdeburg, Germany; Department of Genetics & Molecular Neurobiology, Institute of Biology, Otto-von-Guericke-University Magdeburg, Leipziger Str. 44, 39120 Magdeburg, Germany; Institute of Pharmacology and Toxicology, Otto-von-Guericke-University Magdeburg, Leipziger Str. 44, 39120 Magdeburg, Germany.
| | - Stav Regev-Tsur
- Sagol Department of Neurobiology, University of Haifa, 199 Aba-Hushi Avenue, 3498838 Haifa, Israel; The Integrated Brain and Behavior Research Center (IBBR), University of Haifa, 199 Aba-Hushi Avenue, 3498838 Haifa, Israel.
| | - Oliver Stork
- Center for Behavioral Brain Science, Universitätsplatz 2, 39106 Magdeburg, Germany; Department of Genetics & Molecular Neurobiology, Institute of Biology, Otto-von-Guericke-University Magdeburg, Leipziger Str. 44, 39120 Magdeburg, Germany.
| | - Gal Richter-Levin
- Sagol Department of Neurobiology, University of Haifa, 199 Aba-Hushi Avenue, 3498838 Haifa, Israel; The Integrated Brain and Behavior Research Center (IBBR), University of Haifa, 199 Aba-Hushi Avenue, 3498838 Haifa, Israel; Psychology Department, University of Haifa199 Aba-Hushi Avenue, 3498838 Haifa, Israel.
| |
Collapse
|
22
|
Trompoukis G, Rigas P, Leontiadis LJ, Papatheodoropoulos C. I h, GIRK, and KCNQ/Kv7 channels differently modulate sharp wave - ripples in the dorsal and ventral hippocampus. Mol Cell Neurosci 2020; 107:103531. [PMID: 32711112 DOI: 10.1016/j.mcn.2020.103531] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 07/11/2020] [Accepted: 07/16/2020] [Indexed: 12/14/2022] Open
Abstract
Sharp waves and ripples (SPW-Rs) are endogenous transient patterns of hippocampus local network activity implicated in several functions including memory consolidation, and they are diversified between the dorsal and the ventral hippocampus. Ion channels in the neuronal membrane play important roles in cell and local network function. In this study, using transverse slices and field potential recordings from the CA1 field of rat hippocampus we show that GIRK and KCNQ2/3 potassium channels play a higher role in modulating SPW-Rs in the dorsal hippocampus, while Ih and other KCNQ (presumably KCNQ5) channels, contribute to shaping SPW-R activity more in the ventral than in dorsal hippocampus. Specifically, blockade of Ih channels by ZD 7288 reduced the rate of occurrence of SPW-Rs and increased the generation of SPW-Rs in the form of clusters in both hippocampal segments, while enhanced the amplitude of SPW-Rs only in the ventral hippocampus. Most effects of ZD 7288 appeared to be independent of NMDA receptors' activity. However, the effects of blockade of NMDA receptors depended on the functional state of Ih channels in both hippocampal segments. Blockade of GIRK channels by Tertiapin-Q increased the rate of occurrence of SPW-Rs only in the dorsal hippocampus and the probability of clusters in both segments of the hippocampus. Blockade of KCNQ2/3 channels by XE 991 increased the rate of occurrence of SPW-Rs and the probability of clusters in the dorsal hippocampus, and only reduced the clustered generation of SPW-Rs in the ventral hippocampus. The blocker of KCNQ1/2 channels, that also enhances KCNQ5 channels, UCL 2077, increased the probability of clusters and the power of the ripple oscillation in the ventral hippocampus only. These results suggest that GIRK, KCNQ and Ih channels represent a key mechanism for modulation of SPW-R activity which act differently in the dorsal and ventral hippocampus, fundamentally supporting functional diversification along the dorsal-ventral axis of the hippocampus.
Collapse
Affiliation(s)
- George Trompoukis
- Laboratory of Physiology, Department of Medicine, University of Patras, Rion, Greece
| | - Pavlos Rigas
- Laboratory of Physiology, Department of Medicine, University of Patras, Rion, Greece
| | - Leonidas J Leontiadis
- Laboratory of Physiology, Department of Medicine, University of Patras, Rion, Greece
| | | |
Collapse
|
23
|
Trompoukis G, Papatheodoropoulos C. Dorsal-Ventral Differences in Modulation of Synaptic Transmission in the Hippocampus. Front Synaptic Neurosci 2020; 12:24. [PMID: 32625076 PMCID: PMC7316154 DOI: 10.3389/fnsyn.2020.00024] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 05/14/2020] [Indexed: 11/17/2022] Open
Abstract
Functional diversification along the longitudinal axis of the hippocampus is a rapidly growing concept. Modulation of synaptic transmission by neurotransmitter receptors may importantly contribute to specialization of local intrinsic network function along the hippocampus. In the present study, using transverse slices from the dorsal and the ventral hippocampus of adult rats and recordings of evoked field postsynaptic excitatory potentials (fEPSPs) from the CA1 stratum radiatum, we aimed to compare modulation of synaptic transmission between the dorsal and the ventral hippocampus. We found that transient heterosynaptic depression (tHSD, <2 s), a physiologically relevant phenomenon of regulation of excitatory synaptic transmission induced by paired stimulation of two independent inputs to stratum radiatum of CA1 field, has an increased magnitude and duration in the ventral hippocampus, presumably contributing to increased input segregation in this segment of the hippocampus. GABAB receptors, GABAA receptors, adenosine A1 receptors and L-type voltage-gated calcium channels appear to contribute differently to tHSD in the two hippocampal segments; GABABRs play a predominant role in the ventral hippocampus while both GABABRs and A1Rs play important roles in the dorsal hippocampus. Activation of GABAB receptors by an exogenous agonist, baclofen, robustly and reversibly modulated both the initial fast and the late slow components of excitatory synaptic transmission, expressed by the fEPSPslope and fEPSP decay time constant (fEPSPτ), respectively. Specifically, baclofen suppressed fEPSP slope more in the ventral than in the dorsal hippocampus and enhanced fEPSPτ more in the dorsal than in the ventral hippocampus. Also, baclofen enhanced paired-pulse facilitation in the two hippocampal segments similarly. Blockade of GABAB receptors did not affect basal paired-pulse facilitation in either hippocampal segment. We propose that the revealed dorsal-ventral differences in modulation of synaptic transmission may provide a means for specialization of information processing in the local neuronal circuits, thereby significantly contributing to diversifying neuronal network functioning along the dorsal-ventral axis of hippocampus.
Collapse
Affiliation(s)
- George Trompoukis
- Laboratory of Physiology, Department of Medicine, University of Patras, Patras, Greece
| | | |
Collapse
|
24
|
Gholami M, Hosseinmardi N, Mirnajafi-Zadeh J, Javan M, Semnanian S, Naghdi N, Fathollahi Y. Long-term potentiation enhancing effect of epileptic insult in the CA1 area is dependent on prior-application of primed-burst stimulation. Exp Brain Res 2020; 238:897-903. [PMID: 32166345 DOI: 10.1007/s00221-020-05766-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Accepted: 03/01/2020] [Indexed: 12/13/2022]
Abstract
Herein field recordings were utilized to test the effects of a transient period of pentylenetetrazol (PTZ) treatment on theta-burst long-term potentiation (LTP) at the Schaffer collateral-CA1 synapses as well as RT-PCR was used to investigate the effects of the combination of the pharmacological treatment and the theta-burst LTP induction on the expression of NMDA subunit mRNA in hippocampal slices. The slope of field excitatory postsynaptic potential (fEPSP) was unaffected while the population spike amplitude and area were increased by a transient period of PTZ treatment (3 mM, 10 min). After a theta burst, a brief PTZ exposure can lead to an enhancement of LTP as documented by fEPSP recording. The effect can be blocked by a selective NMDA receptor antagonist DL-AP5. An increase in the expression of GluN2B and GluN2A subunit mRNAs was also shown due to the combined treatment. The results indicate that the combined treatment increases the degree of NMDA-dependent LTP and are in accord with literature data on the subunit alterations of the hippocampal NMDA receptors. Moreover, our experimental paradigm can be used as a new approach to study the relevance of LTP-like phenomena and epileptic mechanisms.
Collapse
Affiliation(s)
- Masoumeh Gholami
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, P.O. Box: 14115-111, Tehran, Iran.,Department of Basic Sciences, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran
| | - Narges Hosseinmardi
- Department of Physiology, Medical School, Shaheed Beheshti University of Medical Sciences, Tehran, Iran.,Neurophysiology Research Center, Medical School, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Javad Mirnajafi-Zadeh
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, P.O. Box: 14115-111, Tehran, Iran
| | - Mohamad Javan
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, P.O. Box: 14115-111, Tehran, Iran
| | - Saeed Semnanian
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, P.O. Box: 14115-111, Tehran, Iran
| | - Nasser Naghdi
- Department of Physiology and Pharmacology, Pasteur Institute of Iran, Tehran, Iran
| | - Yaghoub Fathollahi
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, P.O. Box: 14115-111, Tehran, Iran.
| |
Collapse
|
25
|
Reis SL, Silva HB, Almeida M, Cunha RA, Simões AP, Canas PM. Adenosine A
1
and A
2A
receptors differently control synaptic plasticity in the mouse dorsal and ventral hippocampus. J Neurochem 2019; 151:227-237. [DOI: 10.1111/jnc.14816] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 06/18/2019] [Accepted: 06/25/2019] [Indexed: 12/20/2022]
Affiliation(s)
- Sara L. Reis
- CNC‐Center for Neuroscience and Cell Biology Coimbra Portugal
- Faculty of Medicine University of Coimbra Coimbra Portugal
| | | | | | - Rodrigo A. Cunha
- CNC‐Center for Neuroscience and Cell Biology Coimbra Portugal
- Faculty of Medicine University of Coimbra Coimbra Portugal
| | - Ana P. Simões
- CNC‐Center for Neuroscience and Cell Biology Coimbra Portugal
| | - Paula M. Canas
- CNC‐Center for Neuroscience and Cell Biology Coimbra Portugal
| |
Collapse
|
26
|
Koutsoumpa A, Papatheodoropoulos C. Short-term dynamics of input and output of CA1 network greatly differ between the dorsal and ventral rat hippocampus. BMC Neurosci 2019; 20:35. [PMID: 31331291 PMCID: PMC6647178 DOI: 10.1186/s12868-019-0517-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Accepted: 07/12/2019] [Indexed: 12/13/2022] Open
Abstract
Background The functional heterogeneity of the hippocampus along its longitudinal axis at the level of behavior is an established concept; however, the neurobiological mechanisms are still unknown. Diversifications in the functioning of intrinsic hippocampal circuitry including short-term dynamics of synaptic inputs and neuronal output, that are important determinants of information processing in the brain, may profoundly contribute to functional specializations along the hippocampus. The objectives of the present study were the examination of the role of the GABAA receptor-mediated inhibition, the μ-opioid receptors and the effect of stimulation intensity on the dynamics of both synaptic input and neuronal output of CA1 region in the dorsal and ventral hippocampus. We used recordings of field potentials from adult rat hippocampal slices evoked by brief repetitive activation of Schaffer collaterals. Results We find that the local CA1 circuit of the dorsal hippocampus presents a remarkably increased dynamic range of frequency-dependent short-term changes in both input and output, ranging from strong facilitation to intense depression at low and high stimulation frequencies respectively. Furthermore, the input–output relationship in the dorsal CA1 circuit is profoundly influenced by frequency and time of presynaptic activation. Strikingly, the ventral hippocampus responds mostly with depression, displaying a rather monotonous input–output relationship over frequency and time. Partial blockade of GABAA receptor-mediated transmission (by 5 μM picrotoxin) profoundly influences input and output dynamics in the dorsal hippocampus but affected only the neuronal output in the ventral hippocampus. M-opioid receptors control short-term dynamics of input and output in the dorsal hippocampus but they play no role in the ventral hippocampus. Conclusion The results demonstrate that information processing by CA1 local network is highly diversified between the dorsal and ventral hippocampus. Transient detection of incoming patterns of activity and frequency-dependent sustained signaling of amplified neuronal information may be assigned to the ventral and dorsal hippocampal circuitry respectively. This disparity should have profound implications for the functional roles ascribed to distinct segments along the long axis of the hippocampus. Electronic supplementary material The online version of this article (10.1186/s12868-019-0517-5) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Andriana Koutsoumpa
- Laboratory of Neurophysiology, Department of Medicine, University of Patras, 26504, Rion, Greece.,Molecular Systems Biology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | | |
Collapse
|
27
|
β-adrenergic receptors reduce the threshold for induction and stabilization of LTP and enhance its magnitude via multiple mechanisms in the ventral but not the dorsal hippocampus. Neurobiol Learn Mem 2018; 151:71-84. [PMID: 29653257 DOI: 10.1016/j.nlm.2018.04.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 03/19/2018] [Accepted: 04/07/2018] [Indexed: 12/27/2022]
Abstract
The hippocampus is a functionally heterogeneous structure with the cognitive and emotional signal processing ascribed to the dorsal (DH) and the ventral hippocampus (VH) respectively. However, the underlying mechanisms are poorly understood. Noradrenaline is released in hippocampus during emotional arousal modulating synaptic plasticity and memory consolidation through activation of β adrenergic receptors (β-ARs). Using recordings of field excitatory postsynaptic potentials from the CA1 field of adult rat hippocampal slices we demonstrate that long-term potentiation (LTP) induced either by theta-burst stimulation (TBS) that mimics a physiological firing pattern of hippocampal neurons or by high-frequency stimulation is remarkably more sensitive to β-AR activation in VH than in DH. Thus, pairing of subthreshold primed burst stimulation with activation of β-ARs by their agonist isoproterenol (1 μM) resulted in a reliable induction of NMDA receptor-dependent LTP in the VH without affecting LTP in the DH. Activation of β-ARs by isoproterenol during application of intense TBS increased the magnitude of LTP in both hippocampal segments but facilitated voltage-gated calcium channel-dependent LTP in VH only. Endogenous β-AR activation contributed to the stabilization and the magnitude of LTP in VH but not DH as demonstrated by the effects of the β-ARs antagonist propranolol (10 μM). Exogenous (but not endogenous) β-AR activation strongly increased TBS-induced facilitation of postsynaptic excitability in VH. In DH, isoproterenol only produced a moderate and GABAergic inhibition-dependent enhancement in the facilitation of synaptic burst responses. Paired-pulse facilitation did not change with LTP at any experimental condition suggesting that expression of LTP does not involve presynaptic mechanisms. These findings suggest that β-AR may act as a switch that selectively promotes synaptic plasticity in VH through multiple ways and provide thus a first clue to mechanisms that underlie VH involvement in emotionality.
Collapse
|
28
|
Papaleonidopoulos V, Kouvaros S, Papatheodoropoulos C. Effects of endogenous and exogenous D1/D5 dopamine receptor activation on LTP in ventral and dorsal CA1 hippocampal synapses. Synapse 2018. [PMID: 29537707 DOI: 10.1002/syn.22033] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Hippocampus is importantly involved in dopamine-dependent behaviors and dopamine is a significant modulator of synaptic plasticity in the hippocampus. Moreover, the dopaminergic innervation appears to be disproportionally segregated along the hippocampal longitudinal (dorsoventral) axis with unknown consequences for synaptic plasticity. In this study we examined the actions of endogenously released dopamine and the effects of exogenous D1/D5 dopamine receptor agonists on theta-burst stimulation-induced long-term potentiation (LTP) of field excitatory synaptic potential (fEPSP) at Schaffer collateral-CA1 synapses in slices from dorsal (DH) and ventral hippocampus (VH). Furthermore, we quantified D1 receptor mRNA and protein expression levels in DH and VH. We found that blockade of D1/D5 receptors by SCH 23390 (20 μM) significantly reduced the magnitude of LTP in both DH and VH similarly suggesting that dopamine endogenously released during TBS, presumably mimicking low activity of DA neurons, exerts a homogeneous modulation of LTP along the hippocampal long axis. Moderate to high concentrations of the selective partial D1/D5 receptor agonist SKF 38393 (50-150 μM) did not significantly change LTP in either hippocampal segment. However, the full D1 receptor selective agonist SKF 82958 (10 μM) significantly enhanced LTP in VH but not DH. Furthermore, the expression of D1 receptor mRNA and protein was considerably higher in VH compared with DH. These results suggest that the dynamic range of D1/D5 receptor-mediated dopamine effects on LTP may be higher in VH than DH and that VH may be specialized to acquire information about behaviorally relevant strong stimuli signaled by the dopamine system.
Collapse
Affiliation(s)
| | - Stylianos Kouvaros
- Laboratory of Physiology, Department of Medicine, University of Patras, Rion 26504, Greece
| | | |
Collapse
|
29
|
Dubovyk V, Manahan‐Vaughan D. Less means more: The magnitude of synaptic plasticity along the hippocampal dorso-ventral axis is inversely related to the expression levels of plasticity-related neurotransmitter receptors. Hippocampus 2018; 28:136-150. [PMID: 29171922 PMCID: PMC5814924 DOI: 10.1002/hipo.22816] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Revised: 11/12/2017] [Accepted: 11/21/2017] [Indexed: 11/16/2022]
Abstract
The dorsoventral axis of the hippocampus exhibits functional differentiations with regard to (spatial Vs emotional) learning and information retention (rapid encoding Vs long-term storage), as well as its sensitivity to neuromodulation and information received from extrahippocampal structures. The mechanisms that underlie these differentiations remain unclear. Here, we explored neurotransmitter receptor expression along the dorsoventral hippocampal axis and compared hippocampal synaptic plasticity in the CA1 region of the dorsal (DH), intermediate (IH) and ventral hippocampi (VH). We observed a very distinct gradient of expression of the N-methyl-D-aspartate receptor GluN2B subunit in the Stratum radiatum (DH< IH< VH). A similar distribution gradient (DH< IH< VH) was evident in the hippocampus for GluN1, the metabotropic glutamate receptors mGlu1 and mGlu2/3, GABAB and the dopamine-D1 receptor. GABAA exhibited the opposite expression relationship (DH > IH > VH). Neurotransmitter release probability was lowest in DH. Surprisingly, identical afferent stimulation conditions resulted in hippocampal synaptic plasticity that was the most robust in the DH, compared with IH and VH. These data suggest that differences in hippocampal information processing and synaptic plasticity along the dorsoventral axis may relate to specific differences in the expression of plasticity-related neurotransmitter receptors. This gradient may support the fine-tuning and specificity of hippocampal synaptic encoding.
Collapse
Affiliation(s)
- Valentyna Dubovyk
- Department of NeurophysiologyMedical Faculty, Ruhr University BochumBochum, 44780Germany
- International Graduate School of NeuroscienceRuhr University BochumBochum, 44780Germany
| | - Denise Manahan‐Vaughan
- Department of NeurophysiologyMedical Faculty, Ruhr University BochumBochum, 44780Germany
| |
Collapse
|
30
|
Krania P, Dimou E, Bantouna M, Kouvaros S, Tsiamaki E, Papatheodoropoulos C, Sarantis K, Angelatou F. Adenosine A 2A receptors are required for glutamate mGluR5- and dopamine D1 receptor-evoked ERK1/2 phosphorylation in rat hippocampus: involvement of NMDA receptor. J Neurochem 2018; 145:217-231. [PMID: 29205377 DOI: 10.1111/jnc.14268] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 10/11/2017] [Accepted: 11/24/2017] [Indexed: 12/17/2022]
Abstract
Interaction between mGluR5 and NMDA receptors (NMDAR) is vital for synaptic plasticity and cognition. We recently demonstrated that stimulation of mGluR5 enhances NMDAR responses in hippocampus by phosphorylating NR2B(Tyr1472) subunit, and this reaction was enabled by adenosine A2A receptors (A2A R) (J Neurochem, 135, 2015, 714). In this study, by using in vitro phosphorylation and western blot analysis in hippocampal slices of male Wistar rats, we show that mGluR5 stimulation or mGluR5/NMDARs co-stimulation synergistically activate ERK1/2 signaling leading to c-Fos expression. Interestingly, both reactions are under the permissive control of endogenous adenosine acting through A2A Rs. Moreover, mGluR5-mediated ERK1/2 phosphorylation depends on NMDAR, which however exhibits a metabotropic way of function, since no ion influx through its ion channel is required. Furthermore, our results demonstrate that mGluR5 and mGluR5/NMDAR-evoked ERK1/2 activation correlates well with the mGluR5/NMDAR-evoked NR2B(Tyr1472) phosphorylation, since both phenomena coincide temporally, are Src dependent, and are both enabled by A2A Rs. This indicates a functional involvement of NR2B(Tyr1472) phosphorylation in the ERK1/2 activation. Our biochemical results are supported by electrophysiological data showing that in CA1 region of hippocampus, the theta burst stimulation (TBS)-induced long-term potentiation coincides temporally with an increase in ERK1/2 activation and both phenomena are dependent on the tripartite A2A , mGlu5, and NMDARs. Furthermore, we show that the dopamine D1 receptors evoked ERK1/2 activation as well as the NR2B(Tyr1472) phosphorylation are also regulated by endogenous adenosine and A2A Rs. In conclusion, our results highlight the A2A Rs as a crucial regulator not only for NMDAR responses, but also for regulating ERK1/2 signaling and its downstream pathways, leading to gene expression, synaptic plasticity, and memory consolidation.
Collapse
Affiliation(s)
- Paraskevi Krania
- Physiology Department, Medical School, University of Patras, Patras, Greece
| | - Eleni Dimou
- Physiology Department, Medical School, University of Patras, Patras, Greece
| | - Maria Bantouna
- Physiology Department, Medical School, University of Patras, Patras, Greece
| | - Stylianos Kouvaros
- Physiology Department, Medical School, University of Patras, Patras, Greece
| | - Eirini Tsiamaki
- Physiology Department, Medical School, University of Patras, Patras, Greece
| | | | | | - Fevronia Angelatou
- Physiology Department, Medical School, University of Patras, Patras, Greece
| |
Collapse
|
31
|
Papaleonidopoulos V, Trompoukis G, Koutsoumpa A, Papatheodoropoulos C. A gradient of frequency-dependent synaptic properties along the longitudinal hippocampal axis. BMC Neurosci 2017; 18:79. [PMID: 29233091 PMCID: PMC5727934 DOI: 10.1186/s12868-017-0398-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 12/05/2017] [Indexed: 12/29/2022] Open
Abstract
Background The hippocampus is a functionally heterogeneous brain structure and specializations of the intrinsic neuronal network may crucially support the functional segregation along the longitudinal axis of the hippocampus. Short-term synaptic plasticity plays fundamental roles in information processing and may be importantly involved in diversifying the properties of local neuronal network along the hippocampus long axis. Therefore, we aimed to examine the properties of the cornu ammonis 1 (CA1) synapses along the entire dorsoventral axis of the rat hippocampus using field excitatory postsynaptic potentials from transverse rat hippocampal slices and a frequency stimulation paradigm. Results Applying a ten-pulse stimulus train at frequencies from 0.1 to 100 Hz to the Schaffer collaterals we found a gradually diversified pattern of frequency-dependent synaptic effects along the dorsoventral hippocampus axis. The first conditioned response was facilitated along the whole hippocampus for stimulus frequencies 10–40 Hz. However, steady-state responses or averaged responses generally ranged from maximum synaptic facilitation in the most dorsal segment of the hippocampus to maximum synaptic depression in the most ventral segment of the hippocampus. In particular, dorsal synapses facilitated for stimulus frequency up to 50 Hz while they depressed at higher frequencies (75–100 Hz). Facilitation at dorsal synapses was maximal at stimulus frequency of 20 Hz. On the contrary, the most ventral synapses showed depression regardless of the stimulus frequency, only displaying a transient facilitation at the beginning of 10–50 Hz stimulation. Importantly, the synapses in the medial hippocampus displayed a transitory behavior. Finally, as a whole the hippocampal synapses maximally facilitated at 20 Hz and increasingly depressed at 50–100 Hz. Conclusion The short-term synaptic dynamics change gradually along the hippocampal long axis in a frequency-dependent fashion conveying distinct properties of information processing to successive segments of the structure, thereby crucially supporting functional segregation along the dorsoventral axis of the hippocampus.
Collapse
Affiliation(s)
| | - George Trompoukis
- Department of Medicine, Laboratory of Physiology, University of Patras, 26504, Rion, Greece
| | - Andriana Koutsoumpa
- Department of Medicine, Laboratory of Physiology, University of Patras, 26504, Rion, Greece
| | | |
Collapse
|
32
|
Lee AR, Kim JH, Cho E, Kim M, Park M. Dorsal and Ventral Hippocampus Differentiate in Functional Pathways and Differentially Associate with Neurological Disease-Related Genes during Postnatal Development. Front Mol Neurosci 2017; 10:331. [PMID: 29085281 PMCID: PMC5650623 DOI: 10.3389/fnmol.2017.00331] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Accepted: 09/30/2017] [Indexed: 01/08/2023] Open
Abstract
The dorsal and ventral regions of the hippocampus are important in cognitive and emotional processing, respectively. Various approaches have revealed the differential molecular and structural characteristics, and functional roles of the hippocampus. Recent RNA sequencing (RNA-seq) technology has enriched our understanding of the hippocampus by elucidating more detailed information on gene expression patterns. However, no RNA-seq–based study on gene profiles in the developing hippocampus has been reported. Using RNA-seq–based bioinformatic analysis in conjunction with quantitative real-time polymerase chain reaction analysis and a comparison of in situ hybridization data obtained from the Allen Brain Atlas, we provide a thorough analysis of differentially expressed genes in the dorsal and ventral hippocampus at specific developmental ages representing the postnatally maturing hippocampus. Genes associated with particular functional pathways and marker genes for particular neurological diseases were found to be distinctively segregated within either the dorsal or ventral hippocampus at specific or at all developmental ages examined. We also report novel molecular markers enriched in the dorsal or ventral hippocampus. Taken together, this study provides insights into the molecular mechanisms underlying physiological functions linked to the dorsal or ventral hippocampus. The information provided in the study also contributes to a better understanding of brain functions and serves as a resource for future studies on the pathophysiology of dorsal and ventral hippocampal functions.
Collapse
Affiliation(s)
- A-Ram Lee
- Center for Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology, Seoul, South Korea
| | - Jong-Hwan Kim
- Personalized Genomic Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea.,Department of Functional Genomics, Korea University of Science and Technology, Daejeon, South Korea
| | - Eunsil Cho
- Center for Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology, Seoul, South Korea.,Department of Neuroscience, Korea University of Science and Technology, Daejeon, South Korea
| | - Mirang Kim
- Personalized Genomic Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea.,Department of Functional Genomics, Korea University of Science and Technology, Daejeon, South Korea
| | - Mikyoung Park
- Center for Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology, Seoul, South Korea.,Department of Neuroscience, Korea University of Science and Technology, Daejeon, South Korea
| |
Collapse
|
33
|
Schreurs A, Sabanov V, Balschun D. Distinct Properties of Long-Term Potentiation in the Dentate Gyrus along the Dorsoventral Axis: Influence of Age and Inhibition. Sci Rep 2017; 7:5157. [PMID: 28698637 PMCID: PMC5506024 DOI: 10.1038/s41598-017-05358-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 05/26/2017] [Indexed: 02/07/2023] Open
Abstract
The hippocampus is important for spatial navigation, episodic memory and affective behaviour. Increasing evidence suggests that these multiple functions are accomplished by different segments along the dorsal-ventral (septal-temporal) axis. Long-term potentiation (LTP), the best-investigated cellular correlate of learning and memory, has distinct properties along this axis in the CA1 region, but so far, little is known about longitudinal differences in dentate gyrus (DG). Therefore, here we examined potential dorsoventral differences in DG-LTP using in vitro multi-electrode array recordings. In young mice, we found higher basal synaptic transmission in the dorsal DG, while the LTP magnitude markedly increased towards the ventral pole. Strikingly, these differences were greatly reduced in slices from middle-aged mice. Short-term plasticity, evaluated by paired-pulse ratios, was similar across groups. Recordings in the presence and absence of GABAA-receptor blocker picrotoxin suggested a higher inhibitory tone in the ventral DG of young mice, confirmed by an increased frequency of miniature inhibitory postsynaptic currents. Our findings support the view that the hippocampus contains discrete functional domains along its dorsoventral axis and demonstrate that these are subject to age-dependent changes. Since these characteristics are presumably conserved in the human hippocampus, our findings have important clinical implications for hippocampus- and age-related disorders.
Collapse
Affiliation(s)
- An Schreurs
- KU Leuven, Faculty of Psychology and Educational Sciences, Brain & Cognition, Laboratory of Biological Psychology, Leuven, Belgium
| | - Victor Sabanov
- KU Leuven, Faculty of Psychology and Educational Sciences, Brain & Cognition, Laboratory of Biological Psychology, Leuven, Belgium
| | - Detlef Balschun
- KU Leuven, Faculty of Psychology and Educational Sciences, Brain & Cognition, Laboratory of Biological Psychology, Leuven, Belgium.
| |
Collapse
|
34
|
Prominent differences in sharp waves, ripples and complex spike bursts between the dorsal and the ventral rat hippocampus. Neuroscience 2017; 352:131-143. [DOI: 10.1016/j.neuroscience.2017.03.050] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 03/27/2017] [Accepted: 03/27/2017] [Indexed: 12/17/2022]
|
35
|
Pramipexole restores depressed transmission in the ventral hippocampus following MPTP-lesion. Sci Rep 2017; 7:44426. [PMID: 28290500 PMCID: PMC5349604 DOI: 10.1038/srep44426] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 02/07/2017] [Indexed: 12/18/2022] Open
Abstract
The hippocampus has a significant association with memory, cognition and emotions. The dopaminergic projections from both the ventral tegmental area and substantia nigra are thought to be involved in hippocampal activity. To date, however, few studies have investigated dopaminergic innervation in the hippocampus or the functional consequences of reduced dopamine in disease models. Further complicating this, the hippocampus exhibits anatomical and functional differentiation along its dorso-ventral axis. In this work we investigated the role of dopamine on hippocampal long term potentiation using D-amphetamine, which stimulates dopamine release, and also examined how a dopaminergic lesion affects the synaptic transmission across the anatomic subdivisions of the hippocampus. Our findings indicate that a 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine induced dopaminergic lesion has time-dependent effects and impacts mainly on the ventral region of the hippocampus, consistent with the density of dopaminergic innervation. Treatment with a preferential D3 receptor agonist pramipexole partly restored normal synaptic transmission and Long-Term Potentiation. These data suggest a new mechanism to explain some of the actions of pramipexole in Parkinson´s disease.
Collapse
|
36
|
Staples MC, Fannon MJ, Mysore KK, Dutta RR, Ongjoco AT, Quach LW, Kharidia KM, Somkuwar SS, Mandyam CD. Dietary restriction reduces hippocampal neurogenesis and granule cell neuron density without affecting the density of mossy fibers. Brain Res 2017; 1663:59-65. [PMID: 28284897 DOI: 10.1016/j.brainres.2017.02.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Revised: 02/04/2017] [Accepted: 02/27/2017] [Indexed: 11/25/2022]
Abstract
The hippocampal formation undergoes significant morphological and functional changes after prolonged caloric and dietary restriction (DR). In this study we tested whether prolonged DR results in deleterious alterations in hippocampal neurogenesis, density of granule cell neurons and mossy fibers, all of which support plasticity in the dentate gyrus. Young adult animals either experienced free access to food (control condition), or every-other-day feeding regimen (DR condition) for 3months. The number of Ki-67 cells and 28-day old 5-bromo-2'-deoxyuridine (BrdU) cells were quantified in the dorsal and ventral dentate gyrus to determine the effect of DR on cellular proliferation and survival of neural progenitor cells in the anatomically defined regions of the dentate gyrus. The density of granule cell neurons and synaptoporin were also quantified to determine the effect of DR on granule cell neurons and mossy fiber projections in the dentate gyrus. Our results show that DR increases cellular proliferation and concurrently reduces survival of newly born neurons in the ventral dentate gyrus without effecting the number of cells in the dorsal dentate gyrus. DR reduced density of granule cell neurons in the dorsal dentate gyrus. These alterations in the number of granule cell neurons did not affect mossy fiber density in DR animals, which was visualized as no differences in synaptoporin expression. Our findings demonstrate that granule cell neurons in the dentate gyrus are vulnerable to chronic DR and that the reorganization of granule cells in the dentate gyrus subregions is not producing concomitant alterations in dentate gyrus neuronal circuitry with this type of DR.
Collapse
Affiliation(s)
- Miranda C Staples
- Veterans Medical Research Foundation, VA San Diego Healthcare System, La Jolla, CA, USA
| | - McKenzie J Fannon
- Veterans Medical Research Foundation, VA San Diego Healthcare System, La Jolla, CA, USA
| | - Karthik K Mysore
- Veterans Medical Research Foundation, VA San Diego Healthcare System, La Jolla, CA, USA
| | - Rahul R Dutta
- Veterans Medical Research Foundation, VA San Diego Healthcare System, La Jolla, CA, USA
| | - Alexandria T Ongjoco
- Veterans Medical Research Foundation, VA San Diego Healthcare System, La Jolla, CA, USA
| | - Leon W Quach
- Veterans Medical Research Foundation, VA San Diego Healthcare System, La Jolla, CA, USA
| | - Khush M Kharidia
- Veterans Medical Research Foundation, VA San Diego Healthcare System, La Jolla, CA, USA
| | - Sucharita S Somkuwar
- Veterans Medical Research Foundation, VA San Diego Healthcare System, La Jolla, CA, USA
| | - Chitra D Mandyam
- Veterans Medical Research Foundation, VA San Diego Healthcare System, La Jolla, CA, USA.
| |
Collapse
|