• Title/Summary/Keyword: Brain membranes

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Changes of Glutamate and Polyamine Levels of Hippocampal Microdialysates in Response to Occlusion of Both Carotid Arteries in Mongolian Gerbils (뇌허혈 손상에 있어서 해마-세포외액내 Glutamate와 Polyamine 농도의 변동에 관한 연구)

  • Shin, Kyung-Ho;Kim, Hyung-Gun;Choi, Sang-Hyun;Cho, So-Hyun;Chun, Yeon-Sook;Chun, Boe-Gwun
    • The Korean Journal of Pharmacology
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    • v.30 no.3
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    • pp.273-289
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    • 1994
  • Reversible brain ischemia was produced by occluding both common carotid arteries for 5 min, and the effects of aminoguanidine (AG), $DL-{\alpha}-difluoromethylornithine$ (DFMO), MK-801, and nimodipine (NM) on the ischemia induced changes of the polyamine, glutamate and acetylcholine levels in the hippocampus CA1 subfield and the specific $[^3H]\;MK-801$ binding to the hippocampus synaptosomal membranes were studied with a histological reference of the cresyl violet stained hippocampus. The basal putrescine level $(PT:\;74.4{\pm}8.8\;nM)$ showed a rapid increase (up to 1.7 fold) for 5 min of ischemia, remained significantly increased for 6 h, and then resumed the further increase to amount gradually up to about 3 fold 96 h after recirculation. However, the level of spermidine was little changed, and the spermine level showed a transient increase during ischemia followed by a sustained decrease to about 40% of the preischemic level after recirculation. The increase of PT level induced by brain ischemia was enhanced with AG or MK-801, but it was reduced by DFMO or NM. The basal glutamate level $(GT:\;0.90{\pm}0.l4\;{\mu}M)$ rapidly increased to a peak level of $8.19{\pm}1.14\;{\mu}M$ within 5 min after onset of the ischemia and then decreased to the preischemic level in about 25 min after recirculation. And NM reduced the ischemia induced increase of GT level by about 25%, but AG, DFMO and MK-801 did not affect the GT increase. The basal acetylcholine level $(ACh:\;118.0{\pm}10.5\;{\mu}M)$ did little change during/after brain ischemia and was little affected by AG or NM. But DFMO and MK-801, respectively, produced the moderate decrease of ACh level. The specific $[^3H]\;MK-801$ binding to the hippocampus synaptosomal membrane was little affected by brain ischemia for 5 min. The control value (78.9 fmole/mg protein) was moderately decreased by AG and MK-801, respectively but was little changed by DFMO or NM. The microscopic findings of the brains extirpated on day 7 after ischemia showed severe neuronal damage of the hippocampus, particularly CA1 subfield. NM and AG moderately attenuated the delayed neuronal damage, and DFMO, on the contrary, aggravated the ischemia induced damage. However, MK-801 did not protect the hippocampus from ischemic damage. These results suggest that unlike to the mode of anti-ischemic action of NM, AG might protect the hippocampus from ischemic injury as being negatively regulatory on the N-methyl-D-aspartate (NMDA) receptor function in the hippocampus.

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Ultrastructural Localization of ZnT3 and Zinc Ions in the Mouse Choroid Plexus (생쥐 맥락얼기에 분포하는 ZnT3 및 zinc 이온의 조직화학적 동정)

  • Kim, Sung-Joo;Kim, Yong-Kuk;Sun, Yuan-Jie;Kim, Soo-Jin;Jeong, Young-Gil;Yu, Yun-Cho;Jo, Seung-Mook
    • Applied Microscopy
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    • v.32 no.4
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    • pp.377-383
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    • 2002
  • We have detected the murine zinc transporter, ZnT3, and zinc ions in the mouse choroid plexus by immunocytochemistry (ICC) and zinc selenium autometallography ($ZnSe^{AMG}$), respectively. BALB/c mice served as experimental animals. Routine floating ABC immunocytochemical procedures were used for the ZnT3 immunocytochemistry, and the mice were injected intraperitoneally (i.p.) with sodium selenide (10 mg/kg) for the zinc selenium autometallography. The choroid plexus showed weak immunoreactivity (Ir) for ZnT3. At high magnification, ZnT3-Ir was seen to be located in the choroid epithelium and the connective tissue of the capillaries. At the EM level, a high electron density of ZnT3-immunoreactivity was restricted to vesicle membranes as well as microvilli in the apical membrane. In contrast, immunostaining of ZnT3 was completely absent in the basolateral plasma membrane and other cell organelles. After silver enhancement, fine $ZnSe^{AMG}$ grains were observed in both the epithelial and endothelial cells of the choroid plexus. Few $ZnSe^{AMG}$ grains present in the cell bodies of the choroid epithelial cells were located in multivesicular bodies. It is striking that very many $ZnSe^{AMG}$ grains were observed in the endothelial cells of the capillaries. These findings establish the choroid plexus as a non-neuronal pool of zinc ions in the brain, although the functional significance of this pool is not clear. The choroid epithelium, however, may play an important role in the transportation of zinc between the CSF and brain tissue.

A RETROSPECTIVE EVALUATION OF IMPLANT INSTALLATION WITH MAXILLARY SINUS AUGMENTATION BY LATERAL WINDOW TECHNIQUE (측방접근법을 이용한 상악동거상술 후 임프란트 식립에 대한 후향적 평가)

  • Ki, Se-Il;Yu, Min-Gi;Kim, Young-Joon;Kook, Min-Suk;Park, Hong-Ju;Shet, Uttom Kumar;Oh, Hee-Kyun
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.30 no.5
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    • pp.457-464
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    • 2008
  • Purpose: The aim of this study was to evaluate the clinical results of implants which were installed with maxillary sinus elevation by using lateral window technique. Materials and methods: We performed the maxillary sinus elevation by lateral window technique to 87 patients who visited Dept. of Oral & Maxillofacial Surgery, Chonnam National University Hospital from January, 2003 to January, 2007. When the residual bone height was from 3 mm to 7 mm, the sinus elevation and simultaneous implant installation was mostly performed. When the residual bone height was less than 3 mm, the sinus elevation was performed and the delayed implant installation was done after 5 or 6 months. No artificial membranes were used for coverage of the lateral bony window site and freeze dried fibrin sealant was applied to the grafted bone. The mean follow-up period was 28.5 months (ranged from 10 months to 48 months) Results: 1. Unilateral sinus elevations were performed in 51 patients and bilateral sinus elevations were performed in 36 patients. And the total number of sinus elevation procedure was 123 cases. 2. The sinus elevation and simultaneous implant installation was performed in 89 sinuses and 249 implants were installed. The sinus elevation and delayed implant installation was performed in 44 sinuses and 141 implants were installed. The total number of implants were 390 in 133 sinuses. The average healing period after sinus elevations was 6.1 months in delayed implant installation. 3. Only autogenous bone, autogenous bone mixing with allografts or autogenous bone mixing with xenografts were used as graft materials. 4. The average period from first surgery to second surgery was about 7.2 months. 5. Some patients complications, such as perforation of sinus membrane, swelling, infection and exposure of cover screw. Two implants were removed in the infected sinus. 6. The survival rate of implants with maxillary sinus elevation by lateral window technique was 99.5% and the success rate of implants was 95.1%. Conclusions: These results indicated that the implants which were installed with maxillary sinus elevation by lateral window technique showed high survival and success rates.

Effect of ${\gamma}$-mangostin through the inhibition of 5-hydroxytryptamine$_{2A}$ receptors in 5-fluoro-${\alpha}$-methyltryptamine-induced head-twitch responses of mice

  • Nattaya Chairungsrie;Furukawa, Ken-Ichi;Takeshi Tadano;Kensuke Kisara;Yasushi Ohizumi
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1998.11a
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    • pp.170-170
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    • 1998
  • In order to discover new types of 5-hydroxytryptamine antagonists, we have devoted our attention to investigating naturally occurring compounds having anti-5HT activity in vitro. Recently, ${\gamma}$-mangostin [1,3,6,7-tetrahydroxy-2,8-bis(3-methyl-2-bytenyl)-9H-xanthen-9-one] from the fruit hull of Garcinia mangostana Linn has been shown to be a selective antagonist for 5-hydroxytryptamine$_{2A}$ receptors in smooth muscle and platelets. It is of interesting that y-mangostin which does not have a nitrogen atom, possesses marked 5-$HT_{2A}$ receptor blocking activity. The present study was undertaken to investigate the effects of ${\gamma}$-mangostin on central 5-HT receptors by using animal behavioural models. Intracerebronventricular injection of ${\gamma}$-mangostin (10-40n mol/mouse) inhibited 5-fluoro-${\alpha}$-methyltryptamin (5-FMT) (45 mg kg$^{-1}$, i.p.)-induced head-twitch response in mice in the presence or absence of citalopram (5-HT-uptake inhibitor). Neither the 5-FMT- nor the 8-hydroxy-2-( di-n-propylamino )tetralin (5-HT$_{1A}$-agonist)-induced 5-HT syndrome (head weaving and hindlimb abduction) was affected by ${\gamma}$-mangostin. The locomotor activity stimulated by 5-FMT through the activation of at-adrenoceptors did not alter in the presence of ${\gamma}$-mangostin. 5-HT-induced inositol phosphates accumulation in mouse brain slices was abolished by ketanserin. ${\gamma}$-Mangostin caused a concentration-dependent inhibition of the inositol phosphates accumulation and the binding of [$^3H$]-spiperone, a specific 5-$HT_{2A}$ receptor antagonist, to mouse brain membranes. Kinetic analysis of the [$^H3$]-spiperone binding revealed that ${\gamma}$-mangostin increased the $_{d}$ value without affecting the $B_{max}$ value, indicating the mode of the competitive nature of the inhibition by ${\gamma}$-mangostin. These results suggest that ${\gamma}$-mangostin inhibits 5-FMT-induced head-twitch response in mice by blocking 5-$HT_{2A}$ receptors not by blocking the release of 5-HT from the central neurone. ${\gamma}$-Mangostin is a promising 5-$HT_{2A}$ receptors antagonist in the central nervous system.m.

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An Improved Method for EM Radioautographic Techniques using Cork (EM Radioautographic Techniques에 관(關)한 연구(硏究) - Cork 방법(方法) -)

  • Kim, Myung-Kook;Hassler, R.
    • Applied Microscopy
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    • v.10 no.1_2
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    • pp.7-17
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    • 1980
  • Electron microscope radioautography introduced by Liquier-Milward (1956) is now used routinely in many laboratories. Most of the technical difficulties in specimen preparation have been overcome. This method is modified from loop method for improvement of EM radioautographic techniques. The advantages of this method are: 1. the use of single specimens on small corks and of a large wire loop, allows the experimenter to avoid the blemishes in the membrane; 2. the surfactant dioctyl sodium sulphosuccinate is added to diluted ILford L4, thus greatly prolonging the period of time over which good emulsion layers can be made; 3. corks can be handled in perspex holder which allows about 20 specimens to be developed simultaneously. The steps of the method comprise: 1. Cut ribbons of ultrathin sections of silver interference colour 2. Pick them up on formvar-coated 200 mesh grids 3. Prestaining of tissues 4. Coat the specimens with a thin layer of carbon by evaporation (30-60A) 5. Mount the specimens on corks (about 1cm apical diameter) using double-sided scotch tape 6. Emulsion coating; a. Take a 250m1 beaker, place it on the pan of a sliding weight balance and weigh it. Add 10 grams extra to the beam. Add pieces of ILford L4 emulsion to the beaker until the balance is swinging freely. Add the 20ml of distilled water that was previously measured out. b. Surfactant dioctyl sodium sulphosuccinate is added to diluted ILford L4. 7. Prepare a series of membranes of gelled emulsion with the wire loop and apply one to each cork-borne specimen. 8. Put the specimens away to expose by pushing the corks into short length of PVC tubing, each tube having a small hole in the side 9. Place the tubes in small boxes together with silica gel. 10. Exposure 11. Developer - Kodak Microdol X for 3 minutes 12. Fixer - A perspex holder can be manufactured which allows 20 specimens to be developed simultaneously. 12. Fixer - 30% sodium thiosulfate for 10 minutes 13. Examination with Siemens Elmiskop 1A electron microscope

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Drug research and development tend to hyperlipidemia (이상지질혈증과 치료제 연구개발 경향)

  • Seol, In-Chan
    • Journal of Haehwa Medicine
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    • v.18 no.2
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    • pp.1-12
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    • 2009
  • Most of the cholesterol is synthesized by liver in the body while about one of third is taken via dietary. The main functions of cholesterol is to protect membranes in cell surface, avoid the arterial bleeding by hypertension, and prolong the life of erythrocytes, and so on. However, overload of cholesterol leads to arteriosclerosis associated with leading death cause. Lack of physical activity, emotional and environmental stress, and low intake of protein or vitamin E induce the unbalance between HDL- and LDL-cholesterol so become a basis of ischemic disorders in heart, brain and elsewhere in the body. So far, four major classes of medications for hyperlipidemia are HMG-CoA reductase inhibitors (statins), bile acid sequestrants, nicotinic acid, and fibric acids. The statins can lower LDL and levels triglyceride, but may induce myopathy and an elevation of liver enzyme levels. The bile acid sequestrants lower LDL levels and raise HDL levels with no effect on triglyceride levels but side effects of gastrointestinal (GI) distress, constipation, and a decrease in the absorption of other drugs. Nicotinic acid and fibric acids lower LDL and triglyceride levels with showing flushing, hyperglycemia, hyperuricemia, GI distress, and hepatotoxicity dyspepsia, gallstones, myopathy, and unexplained noncardiac death as adverse effects. Above western drugs lower cholesterol by 15 to 30% while all have notable adverse effects. In traditional medicine, hyperlipidemia is regarded as retention of phlegm and fluid disease. Etiology and pathogenesis of hyperlipidemia is basically based on Spleen-Deficiency and Phlegm-Stagnation, accumulation and stasis of -heat, and Qi & blood stagnation induced by Phlegm-damp, water-dampness, and blood stasis. Thereby, strengthening Spleen and dissolving Phlegm, clearing away heat and diuresis, and supplementing Qi and activating blood circulation are commonly used therapeutic methods for hyperlipidemia. The traditional herbal medicine, have been used for patients with CVA, hypertension or hyperlipidemia in Oriental hospital or Oriental clinic. The lock and key theory is used to develop most of western medicine, however many diseases are caused by mixed factors in body-complex system. We expect that Oriental pharmacological theory could be newborn as a novel drug showing high advantage of blood levels of lipidsand QOL of performance without side effects.

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Synergistic Effect of Staphylococcus aureus and LPS on Silica-Induced Tumor Necrosis Factor Production in Macrophage Cell Line J774A.1

  • LEE DONG HEE;PARK BONG JOO;LEE MIN SUB;CHOI JAE BONG;KIM JEONG KOO;PARK JONG HOON;PARK JONG-CHUL
    • Journal of Microbiology and Biotechnology
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    • v.16 no.1
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    • pp.136-140
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    • 2006
  • In this study, we investigated the synergistic effects of Staphylococcus aureus extracts (membranes and walls) and lipopolysaccharide (LPS) derived from Escherichia coli on tumor necrosis factor (TNF) production in the pathogenesis of silica-induced inflammation. The synergistic induction of TNF by silica particles $(<20\;{\mu}m)$ in combination with either S. aureus extracts or LPS was examined in J774A.1 cell cultures. Media from the treated and untreated cell cultures were assayed for TNF, using the mouse WEHI 164 cell cytotoxicity assay and enzyme immunoassay. Cells exposed simultaneously to silica and $0.5\;{\mu}g/ml$ S. aureus extracts (or 0.5 ng/ml of LPS) produced a significantly higher level of TNF than those produced by the inducer alone. Our results indicate that device-associated infections (or pyrogen contamination) could enhance inflammatory responses, because of particles produced by the wear of medical implants or particulate biomaterials used for clinical purposes.

Effects of Chlorpromazine·HCl on the Structural Parameters of Bovine Brain Membranes

  • Jang, Hye-Ock;Jeong, Dong-Keun;Ahn, Shin-Ho;Yoon, Chang-Dae;Jeong, Soo-Cheol;Jin, Seong-Deok;Yun, Il
    • BMB Reports
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    • v.37 no.5
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    • pp.603-611
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    • 2004
  • Fluorescence probes located in different membrane regions were used to evaluate the effects of chlorpromazine HCl on structural parameters (transbilayer lateral mobility, annular lipid fluidity, protein distribution, and lipid bilayer thickness) of synaptosomal plasma membrane vesicles (SPMVs) isolated from bovine cerebral cortex. The experimental procedure was based on the selective quenching of 1,3-di(1-pyrenyl)propane (Py-3-Py) by trinitrophenyl groups, radiationless energy transfer from the tryptophan of membrane proteins to Py-3-Py, and energy transfer from Py-3-Py monomers to 1-anilinonaphthalene-8-sulfonic acid (ANS). In this study, chlorpromazine HCl decreased the lateral mobility of Py-3-Py in a concentration dependent-manner, showed a greater ordering effect on the inner monolayer than on the outer monolayer, decreased annular lipid fluidity in a dose dependent-manner, and contracted the membrane lipid bilayer. Furthermore, the drug was found to have a clustering effect on membrane proteins.

Membrane Topology of Helix 0 of the Epsin N-terminal Homology Domain

  • Kweon, Dae-Hyuk;Shin, Yeon-Kyun;Shin, Jae Yoon;Lee, Jong-Hwa;Lee, Jung-Bok;Seo, Jin-Ho;Kim, Yong Sung
    • Molecules and Cells
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    • v.21 no.3
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    • pp.428-435
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    • 2006
  • Specific interaction of the epsin N-terminal homology(ENTH) domain with the plasma membrane appears to bridge other related proteins to the specific regions of the membrane that are invaginated to form endocytic vesicles. An additional $\alpha$-helix, referred to as helix 0 (H0), is formed in the presence of the soluble ligand inositol-1,4,5-trisphosphate [$Ins(1,4,5)P_3$] at the N terminus of the ENTH domain (amino acid residues 3-15). The ENTH domain alone and full-length epsin cause tubulation of liposomes made of brain lipids. Thus, it is believed that H0 is membrane-inserted when it is coordinated with the phospholipid phosphatidylinositol-4,5-bisphosphate [$PtdIns(4,5)P_2$], resulting in membrane deformation as well as recruitment of accessory factors to the membrane. However, formation of H0 in a real biological membrane has not been demonstrated. In the present study, the membrane structure of H0 was determined by measurement of electron paramagnetic resonance (EPR) nitroxide accessibility. H0 was located at the phosphate head-group region of the membrane. Moreover, EPR line-shape analysis indicated that no pre-formed H0-like structure were present on normal acidic membranes. $PtdIns(4,5)P_2$ was necessary and sufficient for interaction of the H0 region with the membrane. H0 was stable only in the membrane. In conclusion, the H0 region of the ENTH domain has an intrinsic ability to form H0 in a $PtdIns(4,5)P_2$-containing membrane, perhaps functioning as a sensor of membrane patches enriched with $PtdIns(4,5)P_2$ that will initiate curvature to form endocytic vesicles.

Identification of Three Competitive Inhibitors for Membrane­Associated, $Mg^{2+}-Dependent$ and Neutral 60 kDa Sphingomyelinase Activity

  • Kim Seok Kyun;Jung Sang Mi;Ahn Kyong Hoon;Jeon Hyung Jun;Lee Dong Hun;Jung Kwang Mook;Jung Sung Yun;Kim Dae Kyong
    • Archives of Pharmacal Research
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    • v.28 no.8
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    • pp.923-929
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    • 2005
  • Methanol extracts of domestic plants of Korea were evaluated as a potential inhibitor of neutral pH optimum and membrane-associated 60 kDa sphingomyelinase (N-SMase) activity. In this study, we partially purified N-SMase from bovine brain membranes using ammonium sulfate. It was purified approximately 163-fold by the sequential use of DE52, Butyl-Toyopearl, DEAE-Cellulose, and Phenyl-5PW column chromatographies. The purified N-SMase activity was assayed in the presence of the plant extracts of three hundreds species. Based on the in vitro assay, three plant extracts significantly inhibited the N-SMase activity in a time- and concentration-dependent manner. To further examine the inhibitory pattern, a Dixon plot was constructed for each of the plant extracts. The extracts of Abies nephrolepis, Acer tegmentosum, and Ginkgo biloba revealed a competitive inhibition with the inhibition constant (Ki) of $11.9 {\mu}g/mL,\;9.4{\mu}g/mL,\;and\;12.9{\mu}g/mL$, respectively. These extracts also inhibited in a dose-dependent manner the production of ceramide induced by serum deprivation in human neuroblastoma cell line SH-SY5Y.