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Zhao Y, Peng L, Li X, Zhang Y. Expression of somatostatin and its receptor 1-5 in endometriotic tissues and cells. Exp Ther Med 2018; 16:3777-3784. [PMID: 30405748 PMCID: PMC6201141 DOI: 10.3892/etm.2018.6730] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 03/09/2018] [Indexed: 12/23/2022] Open
Abstract
The present study aimed to detect the expression of somatostatin (SS) and SS receptor (SSTR)1-5 in tissues from patients with endometriosis (EMS). Reverse transcription-quantitative polymerase chain reaction analysis was applied to examine the expression of somatostatin gene in ectopic endometrial cells (EECs). The expression of somatostatin receptor 1–5 in the ectopic endometrium (EE), eutopic endometrium and normal endometrium and their association with EMS staging were determined by immunohistochemistry. The results indicated that the expression of SS in EECs was significantly higher compared with that in the control group. SSTR1-5 were expressed in the EE tissues from 30 patients with EMS, and the positive rates were 43.3, 70.0, 53.3, 50.0 and 96.7%, respectively, which were closely associated with EMS staging of the patients. The positive rates of SSTR1-5 expression in the eutopic endometrium from 12 patients with EMS were 33.3, 41.7, 58.3, 58.3 and 83.3%, respectively, while the positive rates of SSTR1-5 expression in the normal endometrium from 14 women without EMS were 7.1, 7.1, 21.4, 28.6 and 64.3%, which were lower than the positive rates of SSTR1-5 in the EE (43.3, 70, 53.3, 50 and 96.7%) and eutopic endometrial cells (33.3, 41.7, 58.3, 58.3 and 83.3%). In conclusion, SS was highly expressed in EECs. SSTR1-5 were expressed in the ectopic as well as eutopic endometrium, and low or moderate expression of SSTR1-4 and high expression of SSTR5 were detected in the ectopic and eutopic endometrial tissues, while low expression of SSTR1-4 and partial expression of SSTR5 were detected in normal endometrium. The positive rates of expression of SSTR1-5 in the EE cells and eutopic endometrium were higher than those in the normal endometrium. The expression of all the subtypes of SSTR in the EE tissues was closely associated with EMS staging.
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Affiliation(s)
- Yanhua Zhao
- Department of Obstetrics and Gynecology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
| | - Lin Peng
- Reproductive and Stem Cell Research Institute, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
| | - Xiang Li
- Department of Pathology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
| | - Yi Zhang
- Department of Obstetrics and Gynecology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
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2
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Vismer MS, Forcelli PA, Skopin MD, Gale K, Koubeissi MZ. The piriform, perirhinal, and entorhinal cortex in seizure generation. Front Neural Circuits 2015; 9:27. [PMID: 26074779 PMCID: PMC4448038 DOI: 10.3389/fncir.2015.00027] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 05/15/2015] [Indexed: 12/11/2022] Open
Abstract
Understanding neural network behavior is essential to shed light on epileptogenesis and seizure propagation. The interconnectivity and plasticity of mammalian limbic and neocortical brain regions provide the substrate for the hypersynchrony and hyperexcitability associated with seizure activity. Recurrent unprovoked seizures are the hallmark of epilepsy, and limbic epilepsy is the most common type of medically-intractable focal epilepsy in adolescents and adults that necessitates surgical evaluation. In this review, we describe the role and relationships among the piriform (PIRC), perirhinal (PRC), and entorhinal cortex (ERC) in seizure-generation and epilepsy. The inherent function, anatomy, and histological composition of these cortical regions are discussed. In addition, the neurotransmitters, intrinsic and extrinsic connections, and the interaction of these regions are described. Furthermore, we provide evidence based on clinical research and animal models that suggest that these cortical regions may act as key seizure-trigger zones and, even, epileptogenesis.
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Affiliation(s)
- Marta S Vismer
- Department of Neurology, The George Washington University Washington, DC, USA
| | | | - Mark D Skopin
- Department of Neurology, The George Washington University Washington, DC, USA
| | - Karen Gale
- Department of Pharmacology, Georgetown University Washington, DC, USA
| | - Mohamad Z Koubeissi
- Department of Neurology, The George Washington University Washington, DC, USA
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3
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Gao L, Zan L, Wang H, Hao R, Zhong X. Polymorphism of somatostatin gene and its association with growth traits in Chinese cattle. GENETICS AND MOLECULAR RESEARCH 2011; 10:703-11. [DOI: 10.4238/vol10-2gmr1029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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4
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Pilocarpine-induced status epilepticus causes acute interneuron loss and hyper-excitatory propagation in rat insular cortex. Neuroscience 2010; 166:341-53. [DOI: 10.1016/j.neuroscience.2009.12.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2009] [Revised: 12/07/2009] [Accepted: 12/08/2009] [Indexed: 12/31/2022]
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5
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Kwak SE, Kim JE, Choi HC, Song HK, Kim YI, Jo SM, Kang TC. The expression of somatostatin receptors in the hippocampus of pilocarpine-induced rat epilepsy model. Neuropeptides 2008; 42:569-83. [PMID: 18951627 DOI: 10.1016/j.npep.2008.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2008] [Revised: 09/02/2008] [Accepted: 09/03/2008] [Indexed: 11/30/2022]
Abstract
During the course of this study, we sought examine whether the expression of somatostatin receptors (SSTRs) is altered in the hippocampus following pilocarpine-induced status epilepticus (SE) in order to understand the role/function of SSTRs in the hippocampus after epileptogenic insults. SSTR1 and SSTR4 immunoreactivities were increased in the hippocampus at 1 week after SE. At 4 weeks after SE, SRIF1-family (SSTR 2A, SSTR2B, and SSTR5) immunoreactivity was increased only in neuropil. Both SSTR2A and 2B immunoreactivities were increased in CA2-3 pyramidal cells. However, SSTR3 and SSTR4 immunoreactivities were reduced in the CA1 pyramidal cells of epileptic rat due to neuronal loss. In addition, SSTR5 immunoreactivity was reduced in CA2 pyramidal cells and various interneurons. Both SSTR2B and SSTR4 immunoreactivities were increased within microglia following SE. Our findings suggest that increases in neuron-glial SSTR expressions may be closely related to the enhanced inhibition of the dentate gyrus and regulation of reactive microgliosis in the hippocampus of a pilocarpine model of temporal lobe epilepsy.
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Affiliation(s)
- Sung-Eun Kwak
- Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chunchon 200-702, South Korea
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6
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Kim DS, Kim JE, Kwak SE, Kim DW, Choi SY, Kwon OS, Kang TC. Seizure activity selectively reduces 5-HT1A receptor immunoreactivity in CA1 interneurons in the hippocampus of seizure-prone gerbils. Brain Res 2007; 1154:181-93. [PMID: 17493597 DOI: 10.1016/j.brainres.2007.03.084] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2007] [Revised: 03/29/2007] [Accepted: 03/29/2007] [Indexed: 10/23/2022]
Abstract
Since the correlation between the serotonin (5-hydroxytryptamine, 5-HT) system and seizure activity remains to be clarified, we investigated the 5-HT system in the hippocampus of seizure-resistant (SR) and seizure-sensitive (SS) gerbils. There was no difference of the 5-HT system in the hippocampi of young animals (predisposed and juvenile gerbils) in both SR and SS gerbils. 5-HT immunoreactivity in the dorsal raphe nucleus and the median raphe nucleus was also similarly detected in both animal groups. As compared to SR adult gerbils, only 5-HT1A receptor immunoreactivity was selectively reduced in CA1 interneurons within SS adult gerbils. (+/-)-8-hydroxy-2-(di-n-propylamino)tetralin (a 5-HT1A receptor agonist, 1 and 2 mg/kg) markedly reduced paired-pulse inhibition in the CA1 region of SS adult gerbils only. These findings suggest that the selective reduction in 5-HT1A receptor expression on CA1 interneurons of SS adult gerbil may not be developmental defects, but be an acquired compensatory change induced by repeated seizure activity.
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Affiliation(s)
- Duk-Soo Kim
- Department of Anatomy, College of Medicine, Hallym University, Chunchon 200-702, South Korea
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7
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Kim JE, Kwak SE, Kim DS, Won MH, Choi HC, Song HK, Kim YI, Kang TC. Up-regulation of P/Q-type voltage-gated Ca2+ channel immunoreactivity within parvalbumin positive neurons in the rat hippocampus following status epilepticus. Neurosci Res 2007; 57:379-86. [PMID: 17161880 DOI: 10.1016/j.neures.2006.11.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Revised: 10/24/2006] [Accepted: 11/08/2006] [Indexed: 11/18/2022]
Abstract
To identify the roles of VGCC subtypes in damages/impairs of inhibitory transmission during epileptogenesis, we investigated temporal- and spatial-specific alterations in voltage-gated Ca(2+) channel (VGCC) immunoreactivities within parvalbumin (PV, a Ca(2+) binding protein) positive neurons in the rat hippocampus following status epilepticus (SE). Compared to controls, only P/Q-type (alpha1A) VGCC immunoreactivity was enhanced in PV positive neurons at the early point following SE. The alteration in P/Q-type (alpha1A) VGCC immunoreactivity showed an inverse proportionality to that in PV immunoreactivity in the dentate gyrus and the CA1 region. These findings suggest that SE may induce prolonged up-regulation in P/Q-type VGCC expression within PV positive neurons.
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Affiliation(s)
- Ji-Eun Kim
- Department of Anatomy, College of Medicine, Hallym University, Chunchon, Kangwon-Do 200-702, South Korea
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8
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Chen S, Kobayashi M, Honda Y, Kakuta S, Sato F, Kishi K. Preferential neuron loss in the rat piriform cortex following pilocarpine-induced status epilepticus. Epilepsy Res 2006; 74:1-18. [PMID: 17194568 DOI: 10.1016/j.eplepsyres.2006.11.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2006] [Revised: 11/22/2006] [Accepted: 11/29/2006] [Indexed: 11/23/2022]
Abstract
Structures within the piriform cortex (PC) including the endopiriform nucleus (DEN) and pre-endopiriform nucleus (pEn) have been implicated to be involved in seizure genesis in models of temporal lobe epilepsy. We used stereological methods to examine the specificity and extent of neuron loss in the PC of pilocarpine-treated rats. Both 7 days and 2 months post-status epilepticus rats showed significant neuron loss in the pEn and DEN, layer III of the intermediate PC, and layers II and III of the caudal PC. Total losses in the PC were 40 and 46% in 7 days and 2 months post-status epilepticus rats, respectively (p<0.01). The numbers of parvalbumin (PV)- and cholecystokinin (CCK)-immunopositive neuron profiles significantly decreased, and somatostatin (SS)-immunopositive neuron profiles tended to decrease. A large decrease in the number of PV-immunopositive neuron profiles occurred in the pEn, adjoining parts of the DEN and deep layer III of the PC, portions of the DEN bordering the claustrum and agranular insular cortex, and layer III of the caudal PC. The regions with decreased numbers of PV-, CCK-, and SS-immunopositive neuron profiles overlapped with those where many Nissl-stained neurons were lost and many degenerating cell bodies were detected. These results suggest that the decreases in the numbers of PV/SS/CCK-immunopositive neurons are related to neuron loss rather than to a low rate of synthesis of their peptides or proteins.
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Affiliation(s)
- Shaoyun Chen
- Department of Anatomy, Toho University School of Medicine, Omori-nishi 5-21-16, Ota-Ku, Tokyo 143-8540, Japan.
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9
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Kim DS, Kwak SE, Kim JE, Kim JS, Won MH, Kang TC. The selective effects of somatostatin- and GABA-mediated transmissions on voltage gated Ca2+ channel immunoreactivity in the gerbil hippocampus. Brain Res 2006; 1115:200-8. [PMID: 16920080 DOI: 10.1016/j.brainres.2006.07.076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Revised: 07/13/2006] [Accepted: 07/24/2006] [Indexed: 10/24/2022]
Abstract
To identify whether altered expressions of voltage gated Ca(2+) channel (VGCC) are linked to inhibitory transmission abnormalities in the gerbil hippocampus, we investigated the effects of GABA receptor or somatostatin receptor (SST) antagonists/agonists on VGCC immunoreactivity in vivo. VGCC immunoreactivities in the hippocampus were significantly higher in seizure sensitive (SS) gerbils than in seizure resistant (SR) gerbils. P/Q-type VGCC immunoreactivity in the gerbil hippocampus was reduced by enhancement in GABA(A) and GABA(B) receptor-mediated transmission, but not by SST-mediated transmission. N-type VGCC immunoreactivity was reduced only by a SST agonist, whereas L-type (alpha1C) VGCC immunoreactivity was reduced only by a GABA(A) receptor agonist, and L-type (alpha1D) VGCC immunoreactivity was modulated by the GABA(B) receptor acting drugs. These findings provide a comprehensive description of the differential responses of VGCC subunits to alteration in GABAergic or somatostatinergic transmission. These findings also suggest that up-regulated VGCC immunoreactivity may be consequence of the neuronal excitability caused by a reduction in inhibitory neurotransmission in the gerbil hippocampus.
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MESH Headings
- Animals
- Calcium Channels/drug effects
- Calcium Channels/metabolism
- Calcium Channels, L-Type/drug effects
- Calcium Channels, L-Type/metabolism
- Calcium Channels, N-Type/drug effects
- Calcium Channels, N-Type/metabolism
- Calcium Channels, P-Type/drug effects
- Calcium Channels, P-Type/metabolism
- Cell Membrane/drug effects
- Cell Membrane/metabolism
- Disease Models, Animal
- Epilepsy/chemically induced
- Epilepsy/metabolism
- Epilepsy/physiopathology
- Epilepsy, Temporal Lobe/metabolism
- Epilepsy, Temporal Lobe/physiopathology
- GABA Agonists/pharmacology
- GABA Antagonists/pharmacology
- GABA-A Receptor Agonists
- GABA-A Receptor Antagonists
- GABA-B Receptor Agonists
- GABA-B Receptor Antagonists
- Gerbillinae
- Hippocampus/drug effects
- Hippocampus/metabolism
- Hippocampus/physiopathology
- Immunohistochemistry
- Neural Inhibition/drug effects
- Neural Inhibition/physiology
- Neurons/drug effects
- Neurons/metabolism
- Receptors, GABA-A/metabolism
- Receptors, Somatostatin/agonists
- Receptors, Somatostatin/antagonists & inhibitors
- Receptors, Somatostatin/metabolism
- Somatostatin/metabolism
- Synaptic Transmission/drug effects
- Synaptic Transmission/physiology
- gamma-Aminobutyric Acid/metabolism
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Affiliation(s)
- Duk-Soo Kim
- Department of Anatomy, College of Medicine, Hallym University, Chunchon, Kangwon-Do 200-702, South Korea
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10
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Kim JE, Kwak SE, Kim DS, Won MH, Kwon OS, Choi SY, Kang TC. Reduced calcium binding protein immunoreactivity induced by electroconvulsive shock indicates neuronal hyperactivity, not neuronal death or deactivation. Neuroscience 2005; 137:317-26. [PMID: 16226385 DOI: 10.1016/j.neuroscience.2005.08.052] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2005] [Revised: 05/25/2005] [Accepted: 08/22/2005] [Indexed: 11/25/2022]
Abstract
Calcium-binding proteins (CBPs), such as parvalbumin and calbindin D-28k, are useful markers of specific neuronal types in the CNS. In recent studies, expression of CBPs may be indicative of a deactivated neuronal state, particularly epilepsy. However, it is controversial whether altered expression of CBPs in the hippocampus practically indicate neuronal activity. Therefore, the present study was performed to investigate the extent of profiles of expression of CBPs in the rat hippocampus affected by several episodes induced by electroconvulsive shock. In the present study, following electroconvulsive shock expression of CBPs were reduced in the hippocampus in a stimulus-dependent manner, and recovered to the control level at 6 h after electroconvulsive shock. However, paired-pulse responses of the dentate gyrus were transiently impaired by electroconvulsive shock, and immediately normalized to baseline value. In addition, effects of electroconvulsive shock on expression of CBPs and paired-pulse responses were prevented by pretreatment of vigabatrin. These findings suggest that reduced expression of CBPs induced by seizure activity may be indicative of hyperactivity of CBP positive neurons, which is a practical consequence of the abnormal discharge, and that they may play an important role in regulating seizure activity.
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Affiliation(s)
- J-E Kim
- Department of Anatomy, College of Medicine, Hallym University, Chunchon, Kangwon-Do 200-702, South Korea
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11
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Kwak SE, Kim JE, Kim DS, Won MH, Choi HC, Kim YI, Song HK, Choi SY, Kang TC. Differential effects of vigabatrin and zonisamide on the neuropeptide Y system in the hippocampus of seizure prone gerbil. Neuropeptides 2005; 39:507-13. [PMID: 16194568 DOI: 10.1016/j.npep.2005.08.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2005] [Accepted: 08/16/2005] [Indexed: 10/25/2022]
Abstract
Changed neuropeptide Y (NPY) system in the hippocampus has been reported in various experimental epileptic models. However, there have been little data concerning the alteration in the NPY system in the epileptic hippocampus following treatment of anti-epileptic drugs (AEDs). In the present study, therefore, we performed analyses of effects of vigabatrin (VGB) and zonisamide (ZNS) treatment on the NPY system in the hippocampus of the seizure sensitive (SS) gerbils. In SS gerbil, NPY immunoreactivity in the hippocampus was lower than that in seizure resistant gerbil. Following VGB treatment, the number of NPY immunoreactive neurons and NPY mRNA expression were increased in the hilus and the hippocampus proper. In contrast, ZNS treatment markedly elevated only the density of NPY immunoreactive fibers in the dentate gyrus, not in the hippocampus proper, as compared with saline-treated animals. These patterns were observed in the dose-dependent manners. These findings suggest that AEDs treatments may distinctly affect the NPY system in the SS gerbil hippocampus.
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Affiliation(s)
- Sung-Eun Kwak
- Department of Anatomy, College of Medicine, Hallym University, Chunchon 200-702, South Korea
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12
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Kang TC, Kim DS, Yoo KY, Hwang IK, Kwak SE, Kim JE, Jung JY, Won MH, Suh JG, Oh YS. Elevated voltage-gated Ca2+ channel immunoreactivities in the hippocampus of seizure-prone gerbil. Brain Res 2005; 1029:168-78. [PMID: 15542071 DOI: 10.1016/j.brainres.2004.09.040] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2004] [Indexed: 11/20/2022]
Abstract
In present study, we investigated voltage-gated Ca2+ channel (VGCC) expressions in the hippocampus of the Mongolian gerbil and its association with different sequelae of spontaneous seizures, in an effort to identify the epileptogenesis in this animal. In the hippocampus of pre-seizure seizure sensitive (SS) gerbils, VGCC subunit expressions were significantly elevated, as compared with seizure-resistant (SR) gerbils. In 3 h postictal group, the alteration of VGCC expressions showed regional- and neuronal-specific manners; VGCC immunoreactivities in principal neurons were markedly decreased; however, their immunoreactivities in interneurons were significantly elevated. These results are the first comprehensive description of the distribution of VGCC immunoreactivities in the normal and epileptic hippocampus of gerbils, and suggest that these alterations in the hippocampus of the SS gerbil may be related with tissue excitability and have a role in modulating recurrent excitation following seizures.
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Affiliation(s)
- Tae-Cheon Kang
- Department of Anatomy, College of Medicine, Hallym University, Chunchon, Kangwon-Do 200-702, South Korea.
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13
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Kim DS, Yoo KY, Hwang IK, Jung JY, Won MH, Choi SY, Kwon OS, Seo JH, Kang TC. Elevated voltage gated Cl− channel expression enhances fast paired-pulse inhibition in the dentate gyrus of seizure sensitive gerbil. Neurosci Res 2005; 51:45-53. [PMID: 15596240 DOI: 10.1016/j.neures.2004.09.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2004] [Accepted: 09/21/2004] [Indexed: 11/25/2022]
Abstract
The present study was performed to determine whether the voltage gated Cl- channel (CLC) expression is altered in the hippocampus of seizure sensitive (SS) gerbils, and to identify the strong fast paired-pulse inhibition in the dentate gyrus of SS gerbils is associated with altered CLC expression. In the hippocampal proper and the granule cell layer of the dentate gyrus of the SS gerbils, strong CLC-2 immunoreactivity was detected, as compared with seizure resistant (SR) gerbils. In addition, CLC-3 immunoreactivity was observed in the CA1-3 pyramidal cells, and the granule cell and the molecular layer of the dentate gyrus in the SS gerbils, whereas its immunoreactivity was rarely detected in the SR gerbils. However, CLC-3 immunoreactivity in the mossy fiber was reduced, as compared with SR gerbils. Moreover, infusion of the potential CLC inhibitor (4,4'-diisothiocyanostibene-2,2'-disulfanic acid, DIDS) reduced fast paired-pulse inhibition in the dentate gyrus of SS gerbils, although evoked responses in the dentate gyrus between SR and SS gerbils were similarly detected. These findings suggest that enhancement of CLC expression in the dentate gyrus of SS gerbils may be one of the compensatory responses for reduced GABA(A) receptor-mediated fast postsynaptic inhibitory potentials.
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Affiliation(s)
- Duk-Soo Kim
- Department of Anatomy, College of Medicine, Hallym University, Chunchon, Kangwon-Do 200-702, South Korea
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14
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Kwak SE, Kim JE, Kim DS, Jung JY, Won MH, Kwon OS, Choi SY, Kang TC. Effects of GABAergic transmissions on the immunoreactivities of calcium binding proteins in the gerbil hippocampus. J Comp Neurol 2005; 485:153-64. [PMID: 15776449 DOI: 10.1002/cne.20482] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Although reduced calcium binding protein (CBP) immunoreactivities in the epileptic hippocampus have been well established, it has been controversial that these changes may directly indicate neuronal degeneration. In the present study, therefore, we investigated CBP expressions in the gerbil hippocampus following treatment with gamma-aminobutyric acid (GABA) receptor antagonists in order to assess whether altered CBP expressions are the result of either abnormal excitation or indicative of neuronal damage/degeneration. Seizure-sensitive (SS) gerbils showed a loss/decline of CBP immunoreactivities in some hippocampal neurons as compared with seizure-resistant (SR) gerbils. In muscimol (GABA(A) receptor agonist) treated SS gerbils, expression levels of CBP were enhanced as compared with saline-treated SS gerbils. Bicuculline (a GABA(A) receptor antagonist) treatment markedly reduced CBP immunoreactivities in hippocampal neurons of the SR gerbil. Baclofen (a GABA(B) receptor agonist) treatment increased CBP immunoreactivities in the hippocampus of SS gerbils, although its effect was lower than that of muscimol treatment. Moreover, phaclofen (GABA(B) receptor antagonist) treated SR gerbil showed reduction in calbindin D-28K immunoreactivity, not parvalbumin immunoreactivity, in the hippocampus. These findings therefore suggest that reduced CBP immunoreactivities may be the consequence of abnormal discharge caused by loss of GABAergic inhibition rather than an indication of the neuronal damage/degeneration.
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Affiliation(s)
- Sung-Eun Kwak
- Department of Anatomy, College of Medicine, Hallym University, Chunchon, Kangwon-Do 200-702, South Korea
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15
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Kang TC, An SJ, Park SK, Hwang IK, Seo MO, Kim HS, Kang JH, Kwon OS, Won MH. The somatostatin receptors in the normal and epileptic hippocampus of the gerbil: subtype-specific localization and its alteration. Brain Res 2003; 986:91-102. [PMID: 12965233 DOI: 10.1016/s0006-8993(03)03192-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We investigated the distribution of somatostatin receptors (SSTs) in the hippocampi of SR (seizure-resistant) and SS (seizure-sensitive) gerbils in order to characterize the alterations in SST expressions induced by seizure activity. SST2A immunodensity in the hippocampus of SS gerbils was lower than that of SR gerbils, though its localization in the hippocampus was similar in both SR and SS gerbils. SST3 immunodensity in the hippocampus of SS gerbils was lower than in SR gerbils. In SR gerbils, strong SST4 immunoreactivity was detected in the dentate gyrus and in the CA3 region, in contrast little immunoreactivity was detected in these regions in SS gerbils. In SR and SS gerbils, the strong SST5 immunoreactivity in the hippocampus was also detected in the stratum oriens of the CA2-3 regions and the septal area of CA1 region. However, SST5 immunodensity in the stratum radiatum in SS gerbils was lower than in SR gerbils. These results are the first comprehensive description of the distribution of SSTs in the normal and epileptic hippocampus of gerbils, and suggest that these alterations in the hippocampus of the SS gerbil may be related with a regulatory mechanism for seizure activity in these seizure prone animals.
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Affiliation(s)
- Tae-Cheon Kang
- Department of Anatomy, College of Medicine, Hallym University, Chunchon, Kangwon-Do 200-702, South Korea.
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16
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An SJ, Park SK, Hwang IK, Kim HS, Seo MO, Suh JG, Oh YS, Bae JC, Won MH, Kang TC. Altered corticotropin-releasing factor (CRF) receptor immunoreactivity in the gerbil hippocampal complex following spontaneous seizure. Neurochem Int 2003; 43:39-45. [PMID: 12605881 DOI: 10.1016/s0197-0186(02)00195-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Considerable attention has been focused on the role of corticotropin-releasing factor (CRF) in neuropsychiatric disorders and neurodegenerative diseases including epilepsy. Therefore, in the present study, we investigated the temporal and spatial alteration of CRF receptor in the gerbil hippocampal complex in order to characterize the possible changes and associations with different sequelae of spontaneous seizure in these animals. Thirty minutes postictal, a decline in CRF receptor immunoreactivity was observed in the granule cells and hilar neurons. In the subiculum, CRF receptor immunoreactivity was also significantly decreased at this time point. Twenty-four hours after seizure onset, the immunoreactivity in these regions recovered to the pre-seizure level. Moreover, 30 min after seizure in the entorhinal cortex, the density of CRF receptor immunoreactivity began to decrease, particularly in the layers II and III, compared to pre-seizure group. Nevertheless, 24h after seizure onset, CRF receptor immunodensity had recovered to its seizure-sensitive (SS) level. These results suggest that altered CRF receptor expression in the hippocampal complex may affect tissue excitability and seizure activity in SS gerbils.
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Affiliation(s)
- Sung-Jin An
- Department of Anatomy, College of Medicine, Hallym University, Chunchon, 200-702, Kangwon-Do, South Korea
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Kang TC, Park SK, Hwang IK, An SJ, Choi SY, Kwon OS, Baek NI, Lee HY, Won MH. The altered expression of GABA shunt enzymes in the gerbil hippocampus before and after seizure generation. Neurochem Int 2003; 42:239-49. [PMID: 12427478 DOI: 10.1016/s0197-0186(02)00079-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In the present study, the distribution of succinic semialdehyde dehydrogenase (SSADH) and succinic semialdehyde reductase (SSAR) in the hippocampus of the Mongolian gerbil and its association with various sequelae of spontaneous seizure were investigated in order to identify the roles of GABA shunt in the epileptogenesis and the recovery mechanisms in these animals. Both SSADH and SSAR immunoreactivities in the GABAergic neurons were significantly higher in the pre-seizure groups of seizure sensitive (SS) gerbil as compared to those seen in the seizure resistant (SR) gerbils. The distributions of both SSADH and SSAR immunoreactivities in the hippocampus showed significant differences after the on-set of seizure. At 3 h postictal, when compared to the pre-seizure group of SS gerbils, a decline in the immunoreactivities in the perikarya was observed. At 12 h after seizure on-set, the densities of both SSADH and SSAR immunoreactivities were begun to recover to the pre-seizure level of SS gerbils. These results suggest that the GABAergic neurons in the hippocampal complex of the SS gerbil may be highly activated. In addition, the imbalance of GABA shunt expressions in the GABAergic neurons may imply a malfunction of the metabolism of GABAergic neurons in the SS gerbils, and this defect may trigger seizure on-set. Therefore, the initiation of seizure, at least in gerbils, may be the result of a malfunction in GABA shunt in the GABAergic neurons.
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Affiliation(s)
- Tae-Cheon Kang
- Department of Anatomy, College of Medicine, Hallym University, Chunchon 200-702, Kangwon-Do, South Korea.
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Park SK, Choi DI, Hwang IK, An SJ, Suh JG, Oh YS, Won MH, Kang TC. The differential expression of corticotropin releasing factor and its binding protein in the gerbil hippocampal complex following seizure. Neurochem Int 2003; 42:57-65. [PMID: 12441168 DOI: 10.1016/s0197-0186(02)00060-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Considerable attention has been focused on the role of corticotropin releasing factor (CRF) as well as CRF-binding protein (CRF-BP) in neuropsychiatric disorders and neurodegenerative diseases including epilepsy. Therefore, in the present study, we investigated the temporal and spatial alteration of CRF and CRF-BP in the gerbil hippocampal complex in order to characterize the possible changes and associations with different sequelae of spontaneous seizure in these animals. CRF immunoreactivity was shown in the interneurons of the hippocampal complex at 30 min following seizure. Additionally, alteration of CRF-BP immunoreactivity was restricted to the entorhinal cortex after seizure. These results indicate some factors for consideration. First, in the gerbil hippocampal complex, the delayed increase of CRF immunoreactivity, in spite of its excitatory function, may attenuate seizure activity, but may not do so in epileptogenesis. Second, in contrast to the hippocampal complex, the increase in CRF-BP immunoreactivity in the entorhinal cortex following seizure may participate in feedback inhibitory modulation.
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Affiliation(s)
- Seung-Kook Park
- Department of Anatomy, College of Medicine, Hallym University, Chunchon, Kangwon-Do 200-702, South Korea
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Kang TC, Park SK, Hwang IK, An SJ, Bahn JH, Kim DW, Choi SY, Kwon OS, Baek NI, Lee HY, Won MH. Changes in pyridoxal kinase immunoreactivity in the gerbil hippocampus following spontaneous seizure. Brain Res 2002; 957:242-50. [PMID: 12445966 DOI: 10.1016/s0006-8993(02)03566-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
To identify the roles of pyridoxal kinase (PLK) in epileptogenesis and the recovery mechanisms in spontaneous seizure, a chronological and comparative analysis of PLK expression in the gerbil hippocampus was conducted. PLK immunoreactivity in a pre-seizure group of seizure sensitive (SS) gerbils was more strongly detected than that in a seizure resistant (SR) group. The density of PLK immunoreactivity in a 30-min postictal group was significantly lower than that of a pre-seizure group. In a 12 h postictal group, PLK immunodensity recovered to pre-seizure level. The over-expression of PLK in the hippocampus of pre-seizure SS gerbils suggests that PLP play an important role in the modulation of GAD activity and GABA reuptake as mediated by membrane transporter via neurons.
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Affiliation(s)
- Tae Cheon Kang
- Department of Anatomy, College of Medicine, College of Life Science, Hallym University, Kangwon-Do, Chunchon, South Korea.
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Kang TC, An SJ, Park SK, Hwang IK, Bae JC, Suh JG, Oh YS, Won MH. Changes in Na(+)-K(+)-Cl(-) cotransporter immunoreactivity in the gerbil hippocampus following spontaneous seizure. Neurosci Res 2002; 44:285-95. [PMID: 12413657 DOI: 10.1016/s0168-0102(02)00148-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The immunoreactivity of Na(+)-K(+)-Cl(-) cotransporter (NKCC) in the gerbil hippocampus associated with various sequelae of spontaneous seizures were investigated in order to identify the roles of NKCC in the epileptogenesis and the recovery mechanisms in these animals. The NKCC immunoreactivities in the CA2-3 regions, the subiculum and the entorhinal cortex, were significantly more intensified in the pre-seizure group of seizure sensitive (SS) gerbils than in the seizure resistant (SR) gerbils. Following the on-set of seizure, the immunoreactivity of NKCC was significantly changed. In the hippocampal complex except the CA1 region, NKCC immunoreactivity in GABAergic neurons was significantly decreased 30 min after seizure on-set, versus the pre-seizure group. On the other hand, NKCC immunoreactivity was dramatically elevated in the CA1 regions, and 3 h postictal NKCC immunoreactivity increased significantly in the dentate gyrus and the dendrites of the pyramidal cells in the CA2-3 regions. These findings suggest that altered NKCC expression may be associated with seizure activity, and have an important role in the postictal recovery by regulating GABA-mediated inhibitory circuit in the hippocampal complex of the gerbil.
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Affiliation(s)
- Tae-Cheon Kang
- Department of Anatomy, College of Medicine, Hallym University, 200-702 Kangwon-Do, Chunchon, South Korea.
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Kang TC, Park SK, Hwang IK, An SJ, Bahn JH, Kim AY, Choi SY, Kwon OS, Baek NI, Lee HY, Won MH. Chronological changes in pyridoxine-5'-phosphate oxidase immunoreactivity in the seizure-sensitive gerbil hippocampus. J Neurosci Res 2002; 68:785-91. [PMID: 12111839 DOI: 10.1002/jnr.10280] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
To identify the roles of pyridoxine-5'-phosphate (PNP) oxidase in epileptogenesis and the recovery mechanisms in spontaneous seizure, a chronological and comparative analysis of PNP oxidase expression was conducted. PNP oxidase immunoreactivity in a preseizure group of seizure-sensitive (SS) gerbils was detected more strongly than that in a seizure-resistant (SR) group. The density of PNP oxidase immunoreactivity in a 30 min postictal group was significantly lower than that in a preseizure group. In a 12 hr postictal group, PNP oxidase immunodensity had recovered to a preseizure level. The overexpression of PNP oxidase in the hippocampus of preseizure SS gerbils suggests that PNP or pyridoxal 5'-phosphate plays an important role in the modulation of glutamic acid decarboxylase activity and gamma-aminobutyric acid reuptake as mediated by membrane transporter via neurons. In addition, this change in the PNP oxidase immunoreactivity following seizure may be a compensatory response designed to reduce epileptic activity in this animal.
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Affiliation(s)
- Tae-Cheon Kang
- Department of Anatomy, College of Medicine, Hallym University, Chunchon, South Korea.
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Kang TC, Park SK, Hwang IK, An SJ, Bahn JH, Choi SY, Kim JS, Won MH. The decreases in calcium binding proteins and neurofilament immunoreactivities in the Purkinje cell of the seizure sensitive gerbils. Neurochem Int 2002; 40:115-22. [PMID: 11738477 DOI: 10.1016/s0197-0186(01)00085-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In previous studies, it has been reported that Purkinje cell degeneration during seizure is evoked by excitotoxicity due to an increase in the intracellular Ca(2+) level, though calbindin D-28k (CB) and parvalbumin (PV), intracellular free calcium buffers, are abundantly colocalized in these cells. In the present study, we investigated the expressions of CB, PV, neurofilament (NF) 68, 150, 200, and polyphosphorylated epitope in NF (RT 97), in the cerebellum of gerbils to identify the mechanism of Purkinje cell damages induced by seizure. In seizure resistant gerbils, nearly all the Purkinje cells showed CB, PA, NF 150, NF 200 and RT 97 immunoreactivity. In SS gerbils, however, a clear decrease in the number of CB(+) and PV(+) Purkinje cells was observed. The NF and RT 97 immunoreactivities, in the Purkinje cells was also lower (except NF 68), but not absent. These results suggest several points. First, the decrease in the concentrations of CB and PV may render the Purkinje cells more susceptible to intermittent Ca(2+) fluctuations and more prone to accumulating intolerable quantities of Ca(2+). Second, during the Ca(2+)-PV interaction PV plays an important role in facilitating donations of Mg(2+), which is a potent enzyme activator in phosphorylation. Thus the decline in PV concentration also implicated the defects of phosphorylation in the NF. Third, increases in both the intracellular Ca(2+) level and dephosphorylation trigger the degradation of the NF, particularly NF 200. Finally, these degradations in the NF induce the functional defects in Purkinje cell, which then cause Purkinje cell degeneration.
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Affiliation(s)
- Tae Cheon Kang
- Department of Anatomy, College of Medicine, Hallym University, Kangwon-Do, Chunchon 200-702, South Korea
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Kang TC, Kim HS, Seo MO, Choi SY, Kwon OS, Baek NI, Lee HY, Won MH. The temporal alteration of GAD67/GAD65 ratio in the gerbil hippocampal complex following seizure. Brain Res 2001; 920:159-69. [PMID: 11716822 DOI: 10.1016/s0006-8993(01)03056-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In the present study, the distribution of glutamic acid decarboxylase (GAD) isoforms in the hippocampus of the Mongolian gerbil and its association with different sequelae of spontaneous seizure were investigated to identify the roles of balance of GAD isoforms in the epileptogenesis and the recovery mechanisms in these animals. The GAD67/GAD65 ratio in the hippocampus of pre-seizure seizure sensitive (SS) gerbil was approximately 3.5-fold higher as compared to seizure resistant (SR) gerbil. Following seizure, this ratio shifted to the level of SR gerbils up to 12 h postical. Therefore, the mismatched GAD67/GAD65 ratio (imbalance of GAD isoform expressions) in the hippocampus of SS gerbil implies that GABAergic neurons may be highly activated in order to regulate the increased neuronal excitability. In addition, the alteration in this ratio after seizure may be the compensatory response for reduction of epileptic activity in this animal.
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Affiliation(s)
- T C Kang
- Department of Anatomy, College of Medicine, Hallym University, Kangwon-Do 200-702, Chunchon, South Korea
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Kang TC, Kim HS, Seo MO, Park SK, Kwon HY, Kang JH, Won MH. The changes in the expressions of gamma-aminobutyric acid transporters in the gerbil hippocampal complex following spontaneous seizure. Neurosci Lett 2001; 310:29-32. [PMID: 11524150 DOI: 10.1016/s0304-3940(01)02088-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To identify the roles of gamma-aminobutyric acid (GABA) transporter in epileptogenesis and the recovery mechanisms in spontaneous seizure, a chronological and comparative analysis of GABA transporters (GAT) expression was conducted. GAT-1 immunoreactivity was more strongly detected in the pre-seizure group of seizure sensitive (SS) gerbils than that seen in the seizure resistant group. 30 min postictal, the density of GAT-1 immunoreactivity was significantly decreased in the hippocampal complex, as compared to pre-seizure group. 12 h after seizure on-set, the GAT immunodensity recovered to the pre-seizure level. Following the onset of seizure, GAT-3 immunoreactivity remained unchanged. These results suggest that the increase of GAT-1 expression in the SS gerbil hippocampus may affect epileptogenesis in this animal, and the alteration of immunoreactivity following seizure may be compensatory responses to modulate seizure activity.
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Affiliation(s)
- T C Kang
- Department of Anatomy, College of Medicine, Hallym University, Chunchon, Kangwon-Do 200-702, South Korea
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Suh JG, Ryoo ZW, Won MH, Oh YS, Kang TC. Differential alteration of NMDA receptor subunits in the gerbil dentate gyrus and subiculum following seizure. Brain Res 2001; 904:104-11. [PMID: 11516416 DOI: 10.1016/s0006-8993(01)02490-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In the present study, a chronological and comparative analysis of the immunoreactivities of N-methyl-D-aspartate (NMDA) receptor subunits in hippocampus of both seizure resistant (SR) and seizure sensitive (SS) gerbils was made in order to clarify the temporal and spatial alterations of NMDA receptor subunit expressions in the hippocampus complex. The changes in NMDA receptor immunoreactivity in the hippocampi of SS gerbils were restricted to both the dentate gyrus and the subiculum. At 30 min postictal, a decline in NMDA receptor subunit 1 (NR1) immunoreactivity in the suprablade of dentate gyrus was observed. This is in contrast to the enhancement of its immunodensity in the infrablade. At 3 h postictal the NR1 immunoreactivity in the infrablade also declined significantly. At 12 h postictal, its immunoreactivity in the hilar neurons was reduced. The NMDA receptor subunit 2A/B (NR2A/B) immunoreactivity did not alter until 12 h following seizure-onset, when it was slightly decreased in the granule cells and hilar neurons. In the subiculum, NR1 immunoreactivity was significantly decreased, and was almost undetectable in this region until 12 h postictal; in contrast the NR2A/B immunoreactivity in this region increased significantly in this time point. These results suggest that the altering NMDA receptor expression in both the dentate gyrus and subiculum may affect tissue excitability and have an important role in regulating seizure activity in SS gerbils.
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Affiliation(s)
- J G Suh
- Experimental Animal Center, College of Medicine, Hallym University, 200-702, Chunchon, South Korea
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Kang TC, Park SK, Bahn JH, Jeon SG, Jo SM, Cho SW, Choi SY, Won MH. The alteration of gamma-aminobutyric acid-transaminase expression in the gerbil hippocampus induced by seizure. Neurochem Int 2001; 38:609-14. [PMID: 11290386 DOI: 10.1016/s0197-0186(01)00002-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
It is well established that GABA degradation may play a key role in epileptogenesis. However, whether or not the expression of GABA-transaminase (GABA-T), which catalyzes GABA degradation and participates in the neuronal metabolism via GABA shunt, changes chronologically after on-set of seizure remains to be clarified. To identify the change of GABA-T expression in seizure, GABA-T expression in the gerbil hippocampus, associated with different sequelae of spontaneous seizures, was investigated. The distribution pattern of GABA-T immunoreactive neurons in the hippocampus between the seizure-resistant and pre-seizure group of seizure sensitive gerbils was similar. Interestingly, at 30 min postictal, the enhancement of GABA-T immunoreactivity in the perikarya was apparently observed. This contrasted with the decline in GABA-T immunoreactivity in the granular and pyramidal layer. At 12-24 h postictal, GABA-T immunoreactivity in the hilar neurons had declined significantly. However, the GABA-T immunoreactivity in the granular layer increased. These findings suggest that in the gerbil, the alteration in GABA-T expressions may play an important role in the self-recovery mechanism from seizure attack via both GABA degradation and regulation of neuronal metabolism.
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Affiliation(s)
- T C Kang
- Department of Anatomy, College of Medicine, Hallym University, Chunchon 200-702, South Korea
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