• 대한한의학회지
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• 제29권2호
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• pp.21-31
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• 2008

Backgrounds: Singihwan is used "to strengthen inborn energy" and we suspected a protective effect on brain neuron cells. Objectives: The aim of this study was to evaluate the effects of Singihwan (SGH) on traumatic brain injury-induced delayed apoptosis in rat hippocampal dentate gyrus. Methods: For a surgical induction of traumatic brain injury (TBI), a 5 mm diameter stainless rod was used to make traumatic attack from the surface of the brain used by an impactor. The protective effect of the aqueous extract of SGH against TBI in the rat hippocampal dentate gyrus was investigated by using step-down avoidance task, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay, Bax immunohistochemistry, and 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry. Results: The aqueous extract of SGH suppressed the TBI-induced increase in apoptosis and cell proliferation in the hippocampal dentate gyrus. Conclusions: It is possible that the aqueous extract of SGH has a neuroprotective effect on TBI-induced neuronal cell death.

• 대한감각통합치료학회지
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• 제2권1호
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• pp.21-32
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• 2004

Objective : Effect of treadmill exercise on hippocampal neural cell proliferation under normal conditions and alcohol intoxication conditions has been recently studied; however, this effect under sensory stimulation application has not clarified yet. In the present study, the effect of compression stimulation application on hippocampal neural cell proliferation in the dentate gyrus in normal and alcohol intoxicated rats was investigated. Methods : Experimental design: comparative investigation on number of 5-Bromo-2'-deoxyuridine(BrdU)B-positive cells in dentate gyrus 5 days after commencement. Setting: animal laboratory. Participants: male Sprague-Dawley rats of 3weeks old in age weighing $80{\pm}10gm$. Intervention: animals were randomly assigned into 4 groups; control-rest group(n=8), control-compression group(n=8), alcohol intoxication-rest group(n=8) and alcohol intoxication-compression group(n=8). Animals of the alcohol intoxicated groups were injected intraperitoneally with alcohol(2g/kg) twice per day for 3 days. All animals were injected BrdU(50mg/kg) intraperitoneally, and rats compression stimulation application groups were compressed using sphygmomanometer cuff times per day, for 5 days following alcohol administration. Measures: mean number of BrdU-positive cells in dentate gyrus was observed via immunohistochemistry. Results : Compression stimulation application significantly increased the number of BrdU-positive cells in the dentate gyrus. Also, treatment with alcohol for 3 days inhibited cell proliferation, and compression stimulation application alleviated alcohol-induced inhibition of new cell formation. Conclusion : These results suggest the possibility that compression stimulation application may help in improvement following alcohol-induced brain damaged.

• 동의생리병리학회지
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• 제18권1호
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• pp.236-242
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• 2004

Cerebral ischemia resulting from transient or permanent occlusion of cerebral arteries leads to neuronal cell death and eventually causes neurological impairments. Bee venom has been used for the treatment inflammatory disease. In the present study, the effects of bee venom on apoptosis and cell proliferation in the hippocampal dentate gyrus following transient global ischemia in gerbils were investigated using immunohistochemistry for cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2), caspase-3, and 5-bromo-2'-deoxyuridine (BrdU). It was shown that apoptotic cell death and cell proliferation in the hippocampal dentate gyrus were significantly increased following transient global ischemia in gerbils and that treatment of bee venom suppressed the ischemia-induced increase in apoptosis and cell proliferation in the dentate gyrus. The present results also showed that 1 mg/kg bee-venom treatment suppressed the ischemia-induced increasing apoptosis, cell proliferation, and COX-2 expression in the dentate gyrus. It is possible that the suppression of cell proliferation is due to the reduction of apoptotic cell death by treatment of bee venom. In the present study, bee venom was shown to prosses anti-apoptotic effect in ischemic brain disease, and this protective effect of bee venom against ischemia-induced neuronal cell death is closely associated with suppression on caspase-3 expression.

• International Journal of Oral Biology
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• 제33권2호
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• pp.59-64
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• 2008

This study was designed to investigate the changes in the properties of the neuronal setm cells or progenitor cells associated with age-related decline in neurogenesis of the hippocampal dentate gyrus (DG). Active whole cells cycle marker Ki67 (a marker of whole cell cycle)-positive and S phase marker bromodeoxyuridine (BrdU)-positive. Neural stem cells gradually were reduced in the hippocampal subgranular zone (SGZ) in an age-dependant manner after birth (from P1 month to P1 year). The ratio of BrdUpositivecells/Ki67-positive cells was gradually enhanced in an age-dependent manner. The ratio of Ki67-positive cells/accu-mulating BrdU-positive cells at 3 hrs after BrdU injection was injected once a day for consecutive 5 days gradually decreased during ageing. TUNEL- and caspase 3 (apoptotic terminal caspase)-positive cells gradually decreased in the dentate SGZ during ageing and immunohistochemical findings of glial fibrillary acid protein (GFAP) were not changed during ageing. NeuN, a marker of mature neural cells, and BrdU-double positive cells gradually decreased in an age-dependent manner but differentiating ratio and survival rate of cells were not changed at 4 wks after BrdU injection once a day for consecutive 5 days. The number of BrdU-positive cells migrated from the hippocampal SGZ into granular layer and its migration speed was gradually declined during ageing. These results suggest that the adult neurogenesis in the mouse hippocampal DG gradually decrease through reducing proliferation of neural stem cells accompanying with cells cycle change and reduced cells migration rather than changes of differentiation.

• Clinical and Experimental Pediatrics
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• 제45권12호
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• pp.1551-1558
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• 2002

목 적 : 중증 측두엽간질환자와 kainic acid(KA)로 처리한 측두엽간질 동물모델에서 해마 치아이랑의 사이신경세포가 소실된다. 측두엽간질 마우스모델인 마우스해마의 기관형 배양에 의한 KA 간질모델에서 parvalbumin(PV)항체를 이용한 면역조직화학법으로 치아이랑에 분포하는 PV 면역반응성 사이신경세포를 감별염색하여 세포체 및 그 가지돌기의 형태학적 변화를 관찰함으로써 측두엽간질의 병태생리의 일단을 규명하고자 한다. 방 법 : 실험적 간질 모델은 C57/BL6 마우스의 해마박편을 이용한 기관형 배양에서 $10{\mu}M$ KA 투여로 유발시켰으며, PV 항체를 이용한 광학현미경적 면역조직화학법으로 치아이랑에 분포하는 PV 면역반응성 사이신경세포를 감별염색하여 형태학적 차이를 관찰하였고, 또한 이들 세포의 세포수를 계측하고 KA처리 후 배양하면서 시간경과(8, 24, 48, 72시간)에 따라 PV 면역반응성 사이신경세포의 형태학적 변화를 관찰하였다. 결 과: KA 처리를 하지 않고 배양된 해마조직박편(대조군)의 치아이랑에서 PV 면역반응성 세포는 가지돌기 나무가 잘 발달되어 있고 사이신경세포로서 이들은 주로 과립층과 이층 밑의 다형층에 산재하였다. $10{\mu}M$ KA에 1시간 정도 노출되었을 때 PV 면역반응성 사이신경세포의 돌기에는 염주상이 형성되었고 가지돌기는 가늘어져 있었다. PV 면역반응성 사이신경세포는 KA 처리 후 배양액에서 KA를 제거한 뒤 시간이 경과함에 따라 형태학적 회복을 보여주었다. KA 제거 후 8시간 회복군에서 세포돌기의 염주상은 볼 수 없었으며 가지돌기는 가늘어져 있었다. KA 제거 후 24, 48, 72시간 회복군에서도 염주상은 거의 볼 수가 없었으며 가지돌기의 두께도 회복되었다. PV 면역반응성 사이신경세포의 수는 대조군에 비하여 KA 처리군과 KA 제거 후 8시간 회복군에서는 통계학적으로 유의한 세포수의 감소가 있었으나 KA 제거 후 24시간 회복군, KA 제거 후 48시간 회복군 및 KA 제거 후 72시간 회복군에서는 대조군과 차이가 없 었다. 결 론: 이러한 결과는 KA에 의하여 유발된 치아이랑 사이신경세포의 세포소실이 일시적이며 가역적인 현상임을 말해주는 것이다.

• 대한한의학회지
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• 제27권4호
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• pp.105-115
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• 2006

Fucoidan has been shown to exhibit a host of biological activities, including anti-coagulant, anti-thrombotic, anti-tumourigenic, anti-inflammatory, anti-viral, anti-complementary and neuroprotective effects. In the present study, we attempted to determine the effects of Fucoidan on both apoptosis and cell proliferation in the hippocampal CA1 region and the dentate gyrus of gerbils after the induction of transient global ischemia. This experiment involved the use of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay as well as immunohistochemisty for caspase-3 and 5-bromo-2'-deoxyuridine (BrdU). The monosaccharide composition of the purified Fucoidan which had been extracted from Laminaria religiosa was utilized in this study. The present study clearly induces that apoptotic cell death and cell proliferation in the gerbil's hippocampal regions increased significantly following the induction of transient global ischemia and the results of this study also indicate that Fucoidan exerted a suppressive effect on this observed ischemia-induced increase in apoptosis within the CA1 and dentate gyrus, and also suppressed cell proliferation in the dentate gyrus.

• The Korean Journal of Physiology and Pharmacology
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• 제6권3호
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• pp.143-147
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• 2002

Granule cells in dentate gyrus of hippocampus relay information from entorhinal cortex via perforant fiber to pyramidal cells in CA3 region. Their electrical activities are known to be closely associated with seizure activity as well as memory acquisition. Since action potential is a stereotypic phenomena which is based on all-or-none principle of $Na^+$ current, the neuronal firing pattern is mostly dependent on afterpotentials which follows the stereotypic $Na^+$ spike. Granule cells in dentate gyrus show afterdepolarization (ADP), while interneurons in dentate gyrus have afterhyperpolarizaton. In the present study, we investigated the ionic mechanism of afterdepolarization in hippocampal dentate granule cell. Action potential of dentate granule cells showed afterdepolarization, which was characterized by a sharp notch followed by a depolarizing hump starting at about $-49.04{\pm}1.69\;mV\;(n=43,\;mean{\pm}SD)$ and lasting $3{\sim}7$ ms. Increase of extracellular $Ca^{2+}$ from 2 mM to 10 mM significantly enhanced the ADP both in amplitude and in duration. A $K^+$ channel blocker, 4-aminopyridine (4-AP, 2 mM), enhanced the ADP and often induced burst firings. These effects of 10 mM $Ca^{2+}$ and 4-AP were additive. On the contrary, the ADP was significantly suppressed by removal of external $Ca^{2+},$ even in the presence of 4-AP (2 mM). A $Na^+$ channel blocker, TTX (100 nM), did not affect the ADP. From these results, it is concluded that the extracellular $Ca^{2+}$ influx contributes to the generation of ADP in granule cells.

• 생명과학회지
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• 제17권3호통권83호
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• pp.305-311
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• 2007

글루코코르티코이드는 해마 조직에서 대사, 스냅신 형성, apoptosis, 신경세포 생성과 세포에 있어서 수지상의 형태에 영향을 준다. 글루코코르티코이드 호르몬에 의한 해마조직의 생리학적 조절을 이해하기 위하여, CA3와 DG (dentate gyrus)에서 유전자 발현에 대하여 조사하였다. Lewis 쥐에 9.5mg의 코르티코스테론 알약 또는 플라시보 알약을 20일 동안 처리한 후에 올리고머 유전자 칩을 이용하여 유전자 발현을 조사 하였다 (Rat Neurobiology U34 Arrays, Affymetrix). 플라시보 알약을 처리한 쥐에서 32 유전자들이 DG보다 CA3에서 발현이 높았으며, 3개 유전자는 CA3보다 DG에서 높은 발현을 보였다. 코르티코스테론 호르몬 처리에 의한 해마조직의 유전자 발현 형태는 해부학적 구조의 차이를 보였다. 특히, CA3에서 6개의 유전자와 DG에서 41 개의 유전자가 호르몬에 의하여 조절 받았으며, 이중 43개의 유전자가 상승 발현하였으며, 4개의 유전자가 하강 발현 하였다. 이들 유전자를 기능에 의해 분류하면, 13개의 신경전달물질관련 유전자, 5개의 이온채널,4개의 전사인자, 3개의 neurotrophic인자, 1개의 각 사이토카인과 apoptosis관련 유전자, 그리고 5개의 스냅신형성관련 유전자가 해마조직에서 발현의 변화를 보였다. 특히, 스트레스 호르몬에 의하여 CA3에서 BDNF의 감소를 볼 수 있었다. 이러한 결과는 호르몬에 의하여 해마구조의 생리학적인 다양성을 내포 하고 있다.

• 대한물리의학회지
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• 제7권1호
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• pp.11-20
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• 2012

Purpose : This study is intended to examine the repetitive transcranial magnetic stimulation on cognitive function in the focal ischemic stroke rat model. Methods : This study selected 30 Sprague-Dawley rats of 8 weeks. The groups were divided into two groups and assigned 15 rats to each group. Control group: Non-treatment after injured by focal ischemic stroke; Experimental group: application of repetitive transcranial magnetic stimulation(0.1 Tesla, 25 Hz, 20 min/time, 2 times/day, 5 days/2 week) after injured by focal ischemic stroke. To assess the effect of rTMS, the passive avoidance test, spatial learning and memory ability test were analyzed at the pre, 1 day, $7^{th}$ day, $14^{th}$ day and immunohistochemistric response of BDNF were analyzed in the hippocampal dentate gyrus at $7^{th}$ day, $14^{th}$ day. Results : In passive avoidance test, the outcome of experimental group was different significantly than the control group at the $7^{th}$ day, $14^{th}$ day. In spatial learning and memory ability test, the outcome of experimental group was different significantly than the control group at the $7^{th}$ day, $14^{th}$ day. In immunohistochemistric response of BDNF in the hippocampal dentate gyrus, experimental groups was more increased than control group. Conclusion : These result suggest that improved cognitive function by repetitive transcranial magnetic stimulation after focal ischemic stroke is associated with dynamically altered expression of BDNF in hippocampal dentate gyrus and that is related with synaptic plasticity.

• The Korean Journal of Physiology and Pharmacology
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• 제22권2호
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• pp.145-153
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• 2018

The subgranular zone (SGZ) of hippocampal dentate gyrus (HDG) is a primary site of adult neurogenesis. Toll-like receptors (TLRs), are involved in neural system development of Drosophila and innate immune response of mammals. TLR2 is expressed abundantly in neurogenic niches such as adult mammalian hippocampus. It regulates adult hippocampal neurogenesis. However, the role of TLR2 in adult neurogenesis is not well studied in global or focal cerebral ischemia. Therefore, this study aimed to investigate the role of TLR2 in adult neurogenesis after photochemically induced cerebral ischemia. At 7 days after photothrombotic ischemic injury, the number of bromodeoxyuridine (BrdU)-positive cells was increased in both TLR2 knock-out (KO) mice and wild-type (WT) mice. However, the increment rate of BrdU-positive cells was lower in TLR2 KO mice compared to that in WT mice. The number of doublecortin (DCX) and neuronal nuclei (NeuN)-positive cells in HDG was decreased after photothrombotic ischemia in TLR2 KO mice compared to that in WT mice. The survival rate of cells in HDG was decreased in TLR2 KO mice compared to that in WT mice. In contrast, the number of cleaved-caspase 3 (apoptotic marker) and the number of GFAP (glia marker)/BrdU double-positive cells in TLR2 KO mice were higher than that in WT mice. These results suggest that TLR2 can promote adult neurogenesis from neural stem cell of hippocampal dentate gyrus through increasing proliferation, differentiation, and survival from neural stem cells after ischemic injury of the brain.