• Applied Microscopy
• /
• v.41 no.4
• /
• pp.235-248
• /
• 2011

Traumatic brain injury (TBI) is one of the leading causes of death and disability in children and adults and is a major risk factor for the development of posttraumatic epilepsy (PTE). Recent studies have provided significant insight into the pathophysiological mechanisms underlying the development of epilepsy. Although the link between brain trauma and epilepsy is well recognized, the complex biological mechanisms that result in PTE following TBI have not been fully elucidated. Therefore, this study investigated in order to identify whether or not the abnormal expression of calcium-binding proteins in the lesioned hippocampus plays a role in neuronal damage by brain trauma and whether or not the expressions may change in the contralateral hippocampus during the adaptive stage as early time point following TBI. During early time point following TBI, both parvalbumin (PV) and calbindin D-28k (CB) immunoreactivities were decreased with in the lesioned hippocampus. However, these expressions were recovered to control levels as depend on time courses. On the other hand, PV immunoreactivity in contralateral hippocampus was transiently reduced as compared to the control levels, whereas CB expression was unchanged. These findings indicate that the alterations of the calcium-binding proteins, especially PV and CB, may contribute to the neuronal death and/or damage induced by abnormal inhibitory neurotransmission at early time period following brain trauma and the development of epileptogenesis in patients with traumatic brain injury.

• Clinical and Experimental Pediatrics
• /
• v.52 no.5
• /
• pp.588-593
• /
• 2009

Purpose : To investigate whether growth hormone (GH) has a protective effect on neurons in hippocampal slice cultures of neonatal rats exposed to oxygen-glucose deprivation (OGD). Methods : Cultured hippocampal slices of 7-day-old rats were exposed to OGD for 60 min. Then, the slices were immediately treated with three doses of GH (5, 50, or $500{\mu}M$) in media. The relative fluorescent densities of propidium iodide (PI) uptake in the slices and relative lactate dehydrogenase (LDH) activities in the media were determined and compared between each GH- treated group of slices and untreated slices (control) at 12 and 24 h after OGD. Immunofluorescent staining for caspase-3 and TUNEL staining were performed to observe the effect of GH on apoptotic neuronal death. Results : The relative fluorescent densities of PI uptake in CA1 and dentate gyrus (DG) of the hippocampal slices in each GH-treated group were not significantly different from those in the untreated slices at 12 and 24 h after OGD (P>0.05). Treatment with GH could reduce the relative LDH activities in the media of the GH-treated groups only at 12 h after OGD (P<0.05). Expression of caspase-3 and TUNEL positivity in CA1 and DG of the slices treated with 50-iM GH were not different from those of the untreated slices at 12 and 24 h after OGD. Conclusion : Treatment of hippocampal slice cultures with GH after OGD does not show a definitive protective effect on neuronal death but can reduce the LDH efflux of the slices in media at 12 h after OGD.

• Journal of Sasang Constitutional Medicine
• /
• v.11 no.2
• /
• pp.283-299
• /
• 1999

1. Purpose : Systemic injection of kainic acid in experimental animals induces the limbic seizure and structural damages in hippocampus and amygdala which resembles the changes in human temporal lobe epilepsy. The author performed this study to investigate the neuroprotective effects of Yuldahansotang, on the neurotoxicity induced by kainic acid in the hippocampus in rats. 2. Method : Kainic acid was administered intraperitoneally. And feeding with Yuldahansotang for 3 weeks after kainic acid administration. Seizure were induced in male mice (kainate 10-40 mg/kg i.p) and animals were sacrified at various time-points after injection. The experimental animals were sacrificed at 1, 2, 3day and 1, 3weeks while Yuldahansotang administrations. Seizure were graded using a behavioral scale developed in our laboratory. c-fos belong to immediate early genes(IEGs) known to have rapid and brief responses. And neuronal injury was assayed by examining DNA fragmentation using in situ nick translation histochemistry. 3. Results & Conclusion : Seizure severity paralled kainate dosage. At higher doses DNA fragmentation is seen mainly in hippocampus in area CA3, and variable in CA1, thalamus, amygdala within 24 h, is maximal within 72 h, and is large gene by 7 days after administration of kainate. And we can't see the expression of DNA fragmentation and c-fos in the mice what feeded by Yuldahansotang after 7 days from kainic acid administration. It is consequently suggested that Yuldahansotang may attenuate the kainic acid-induced neuronal degeneration and increase the immunoreactivity of hippocampus in mouse.

• Journal of Life Science
• /
• v.16 no.6
• /
• pp.955-959
• /
• 2006

A dynamic cycle of addition and removal of O-linked N-acetylglucosamine (O-GlcNAc) at serine and threonine residues is emerging as a key regulator of nuclear and cytoplasmic protein activity. In this work, immunocytochemistry was carried out to investigate the subcellular expression of GlcNAc kinase (NAGK, EC 2.7.1.59) that catalyzes the phosphorylation of GlcNAc to GlcNAc 6-phosphate. Immunostainings of cultured rat hippocampal neurons revealed patchy or punctate distribution of NAGK. When NAGK is doublestained with caveolin-1 or flotillin, markers for caveolae and lipid rafts, respectively, NAGK was co-localized with these markers. These results indicate that most, if not all, of the NAGK immunopunctae represent caveolae and lipid rafts, and suggest NAGK's role in these membrane microdomains.

• Clinical and Experimental Pediatrics
• /
• v.49 no.2
• /
• pp.198-202
• /
• 2006

Purpose : Fas is a cell surface receptor that transduces apoptotic death signals. Interaction of extracelluar domain of Fas with Fas ligand(FasL) triggers the apoptotic process in many diseases. We investigated the expression of Fas and FasL in the hippocampus of 7-day-old newborn rat brains following hypoxia-ischemia injury. Methods : The 7-days-old newborn rats were exposed to 8 percent oxygen for two hours after the ligation of right common carotid arteries. The newborn rats were killed and their brains were removed at 12, 14 and 48 hours after hypoxic-ischemic injury. The expressions of Fas and FasL of the right hippocampus were observed by western blotting and immunofluorescent staining. Results : Fas and FasL were strongly expressed in the right hippocampus ipsilateral to the ligation of the common carotid artery by western blotting at 12 hours following hypoxic-ischemic injury, and then slowly decreased. The immunofluorescent expressions of Fas and FasL strongly increased in the CA1 area of the right hippocampus at 12 and 24 hours following hypoxic-ischemic injury. The immunofluorescent expression of Fas decreased at 48 hours, but the expression of FasL persisted strongly at 48 hours following hypoxic-ischemic injury. Conclusion : The interaction of Fas with FasL on the cell surface may be involved in neuronal injury following hypoxic-ischemic injury in the developing brain.

• Journal of Digital Convergence
• /
• v.18 no.3
• /
• pp.267-273
• /
• 2020

To determine the biological effects of exercise on hippocampus in mice brain exposed to radiofrequency radiaton (RF), the expression of AMPKα, p-AMPKα, ERK1/2, p-ERK1/2, p38, and p-p38 protein in the mouse exposed to RF were investigated in the hippocampal tissues, Western blot method was used to compare the protein expression levels for each molecule. Significant increases in protein expression of individual and phosphorylated molecules were observed in the spontaneous exercise group, and the expression of these molecules was notably decreased in the RF exposure and spontaneous exercise group. This study shows that neuroplasticity can be increased by exercise in hippocampus that is responsible for memory, but memory and cognitive function may be affected by exposure to RF. We may expect clinically interesting results on dementia or Alzheimer disease if we proceed further investigation on the effect of RF.

• Journal of Life Science
• /
• v.17 no.3 s.83
• /
• pp.305-311
• /
• 2007

Glucocorticoids (GCs) alter metabolism, synaptogenesis, apoptosis, neurogenesis, and dendritic morphology in the hippocampus. To better understand how glucocorticoids regulate these aspects of hippocampal biology, we studied gene expression patterns in the CA3 (Hippocampal pyramidal cell field CA3) and dentate gyrus (DG). Litter-matched Lewis inbred rats treated for 20 days with either 9.5 mg per day sustained-release corticosterone or placebo pellets were compared with high-density oligonucleotide microarray analysis (Rat Neurobiology U34 Arrays, Affymetrix). In placebo-treated rats, 32 genes were expressed at greater levels in CA3 than DG, whereas 3 genes were expressed at great levels in DC than CA3. Regional differences were also apparent in corticosterone-induced changes in the hippocampal transcriptome. Six genes in CA3 and 41 genes in DC were differentially regulated by corticosterone. As per the glucocorticoid effects on gene transcription in the brain, forty three of these genes were upregulated, and 4 genes were downregulated. Genes differentially expressed in hippocampus included those for 13 neurotransmitter proteins, 5 ion channel related proteins, 4 transcription factors, 3 neurotrophic factors, 1 cytokine, 1 apoptosis related protein, and 5 genes involved in synaptogenesis. Interestingly, GCs can have suppressive effects on brain BDNF mRNA transcription, one of the neurotrophic factors. These results indicate the diversity of targets affected by chronic exposure to corticosterone and highlight important regional differences in hippocampal neurobiology.

• Journal of Acupuncture Research
• /
• v.23 no.3
• /
• pp.215-229
• /
• 2006

목적 : 당귀는 전통적으로 학습과 기억능력 증진 및 각종 질병치료에 우수한 효과가 있는 것으로 알려져있다. 본 연구에서는 이러한 인삼약침이 소음스트레스가 유발된 태아쥐의 해마 및 시상하부에서 nitric oxide synthase에 미치는 영향을 관찰하였다. 방법 : 당귀약침이 소음스트레스에 미치는 영향을 연구하기 위하여 태아기에 소음스트레스를 유발하고 생후 4주후 7일간 당귀약침을 투여한 후 NADPH-d 조직화학법을 시행하였다. 결과 : 1. 소음스트레스는 태아쥐의 해마 및 시상하부에서 NOS 발현이 유의하게 증가하였다. 2. 당귀약침은 해마 CAI에서만 소음스트레스에 의해서 증가된 NOS 발현을 유의하게 억제하였다. 3. 당귀약침은 시상하부 PVN, DMH 및 LHA에서 소음스트레스에 의해서 증가된 NOS 발현을 유의하게 억제하였다. 결론 : 본 연구를 통하여 당귀약침이 소음스트레스가 유발된 태아쥐의 해마 및 시상하부에서 증가된 NOS 발현을 유의하게 억제시켜 태아의 스트레스 자극에 당귀약침치료가 유의한 효과가 있음을 확인하였다.

• Korean Journal of Acupuncture
• /
• v.23 no.4
• /
• pp.157-167
• /
• 2006

목적 : 인삼은 전통적으로 학습과 기억능력 증진 및 각종 질병치료에 우수한 효과가 있는 것으로 알려져 있다. 본 연구에서는 이러한 인삼약침이 소음스트레스가 유발된 태아쥐의 해마 및 시상하부에서 nitric oxide synthase에 미치는 영향을 관찰하였다. 방법 : 인삼약침이 소음스트레스에 미치는 영향을 연구하기 위하여 태아기에 소음스트레스를 유발하고 생후 4주 후 7일간 인삼약침을 투여한 후 NADPH-d 조직화학법을 시행하였다. 결과 : 소음스트레스는 태아쥐의 해마 및 시상하부에서 NOS 발현이 유의하게 증가하였다. 2. 인삼약침은 해마 CA1에서만 소음스트레스에 의해서 증가된 NOS 발현을 유의하게 억제하였다 3. 인삼약침은 시상 하부 PVN, DMH 및 LHA에서 소음스트레스에 의해서 증가된 NOS 발현을 유의하게 억제하였다. 결론 : 본 연구를 통하여 인삼약침이 소음스트레스가 유발된 태아쥐의 해마 및 시상하부에서 증가된 NOS 발현을 유의하게 억제시켜 태아의 스트레스 자극에 인삼약침치료가 유의한 효과가 있음을 확인하였다.

• Radiation Oncology Journal
• /
• v.23 no.3
• /
• pp.157-160
• /
• 2005

Purpose: To investigate the effect of low dose radiation on neuronal cell proliferation In diabetic rats. Materials and Methods: A group of rats (first group) were divided into three subgroups (nondiabetic control, nondiabetic 0.1 Gy and nondiabetic 10 Gy groups) to determine the effect of radiation on normal hippocampal neuronal ceil proliferation. A further group of rats (second group) were divided into six subgroups (nondiabetic control, diabetic control, diabetic 0.01 Gy, diabetic 0.1 Gy, diabetic 1 Gy and diabetic 10 Gy groups) to determine the effect of radiation on hippocampal neuronal cell proliferation under diabetic conditions. Using immuno-histochemistry for 5-bromo-2'-deoxyuridine (BrdU), the number of neuronal cells in the dentate gyrus of all the groups was counted. Results: The number of BrdU-positive cells in the dentate Gyrus of the nondiabetic control, nondiabetic 0.1 Gy and nondiabetic 10 Gy subgroups of the first group were $45.95{\pm}3.42,\;59.34{\pm}5.20\;and\;19.26{\pm}2.98/mm^2$, respectively. The number of BrdU-positive cells in the dentate gyrus of the diabetic control, diabetic 0.01 Gy, diabetic 0,1 Gy, diabetic 1 Gy and diabetic 10 Gy subgroups of the second group were $55.44{\pm}8.57,\;33.33{\pm}6.46,\;67.75{\pm}10.54,\;66.63{\pm}10.05,\;23.59{\pm}6.37\;and\;14.34{\pm}7.22/mm^2$, respectively. Conclusion: Low dose radiation enhances cell proliferation in the dentate gyrus of STZ-induced diabetic rats.