• Title/Summary/Keyword: The $\alpha$-Effect

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Effects of the Endothelium on the Contractile Responses to Norepinephrine in Isolated Proximal and Distal Coronary Artery of Pigs

  • Kim, Jong-Hoon;Jeon, Byeong-Hwa;Chang, Seok-Jong;Park, Hae-Kun
    • The Korean Journal of Physiology
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    • 제27권1호
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    • pp.27-35
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    • 1993
  • Effects of the endothelium on the contractile responses to norepinephrine (NE) were investigated in isolated helical strips of the proximal and distal coronaries artery of pigs. The helical strips were immersed in Tris-buffered Tyrode's solution equilibrated with 100% $O_2$ at $35^{\circ}C$ and its isometric tension was measured. NE relaxed the strips precontracted with acetylcholine from both the proximal and distal coronary artery. NE-induced relaxation, which might be induced mainly by $\beta$-adrenoceptor function was dominant in the distal coronary arteries. NE-induced relaxation was converted to a contraction after $\beta$-adrenoceptor blockade with propranolol $(3{\times}10^{-6}M)$. ${\alpha}$-adrenoceptor-mediated contraction by NE was greater in the proximal coronary artery than the distal coronary artery. Quantitatively, ${\alpha}_1$-adrenoceptor mediated contraction by NE was greater than ${\alpha}_2$-adrenoceptor mediated contraction by NE in both arteries. NE-induced relaxation was decreased by rubbing of endothelium in both arteries. ${\alpha}_1-and\;{\alpha}_2$-adrenoceptor mediated contraction by NE were potentiated by rubbing of endothelium in both arteries. Pretreatment with methylene blue, an inhibitor of soluble guanylate cyclase, increased ${\alpha}_1-\;and\;{\alpha}_2$-adrenoceptor mediated contraction by NE in both arteries with endothelium. From the above results, we suggest that the effect of activation of $\alpha$-adrenoceptors by NE may be modulated by endothelium in the proximal and distal coronary arteries of pigs. This effect may be mediated via endothelium derived relaxing factor.

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The Effects of Danchunwhangagam on LPS or DFX-induced Cytokine Production in Peripheral Mononuclear Cells of Cerebral Infarction Patients

  • Son, Ji-Young;Lee, Key-Sang
    • 대한한의학회지
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    • 제26권4호
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    • pp.1-11
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    • 2005
  • This study was to investigate the effect of Danchunwhangagam(DCWGG) extract on the production of proinflammatory cytokines in peripheral blood mononuclear cells (PBMCs) from Cerebral infarction(CI) patients. Methods: We examined how the inhibition rate of tumor necrosis factor (TNF)-$\alpha$, interleukin(IL)-1$\alpha$, IL-1$\beta$, IL-6, and IL-8 productions in DCWGG pretreatment PBMCs culture supernatant in the lipopolysaccaride(LPS)- or desferrioxamine(DFX)treated cells compared to unstimulated cells. Results: DCWGG inhibited the productions of TNF-$\alpha$, IL-1$\alpha$, IL-1$\beta$, IL-6, and IL-8 induced by LPS in a dose-dependent manner. Conclusions: DCWGG might have regulatory effects on LPS or DFX-induced cytokine production, which might explain its beneficial effect in the treatment of CI.

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Effects of Platelet-Activating Factor on Tumor Necrosis $Factor-_{\alpha}$ Production by Muramyl Dipeptide- or Silica-Stimulated Alveolar Macrophages

  • Lee, Ji-Hee;Hah, Jong-Sik
    • The Korean Journal of Physiology
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    • 제30권1호
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    • pp.77-83
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    • 1996
  • Platelet-activating factor(PAF) is a phospholipid mediator of pulmonary inflammation, and immunologic reaction. In this study, the role of PAF on tumor necrosis factor$(TNF_{-{\alpha}})$ production by rat alveolar macrophages(AM) was examined. When PAF $(10^{-12}{\sim}10{-16}\;M)$ alone was added to AM culture, $(TNF_{-{\alpha}})$ production was not significantly increased above the resting level. In contrast, the combined addition of PAF $(10^{-6}\;M)$ and muramyl dipeptide(MDP) $(1.0\;{\mu}g\ml)$ to AM cultures markedly enhanced $(TNF_{-{\alpha}})$ production with 8.2 fold increase compared with AM culture in resting state. This potentiative effect was 313% above the sum of the separate effects of PAF and MDP. To characterize MDP effects on $(TNF_{-{\alpha}})$ production, the dose-response of AM cultured with various concentrations of MDP was tested. High level of MDP $(10\;{\mu}g\ml)$ could not significantly enhance the potentiation effect on $(TNF_{-{\alpha}})$ production compared with AM cultures with low level of MDP $(0.1\;{\mu}g\ml)$, i.e. 112.5% vs 107.8%, respectively when $10^{-10}$ M of PAF was simultaneously added to the cell culture. These data support that the potentiation of TNF. g production in AM culture is mediated by PAF rather than MDf It was also evaluated whether the similar result was obtained in silica, respirable toxic particle-treated AM culture. $(TNF_{-{\alpha}})$ production was also significantly enhanced in the PAF $(10^{-6}\;M)$ and silica $(50\;{\mu}g\ml)$-added cell cultures with 4.7 fold above the value of silica alone-stimulated cells. These results indicate that PAF can potentiate $(TNF_{-{\alpha}})$ production by MDP-or silica- stimulated AM and suggest that PAF may play a potent role in lung inflammation and disease associated with microbe and occupational dust exposures.

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Polymeric Acetate-Selective Electrodes Based on meso-(α,α,α,α)-Tetrakis-[(2-arylphenylurea)phenyl]porphyrins: Electormic and pH Effects

  • Lee, Hyo-Kyoung;Song, Ki-ju;Seo, Hyung-Ran;Jeon, Seung-won
    • Bulletin of the Korean Chemical Society
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    • 제23권10호
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    • pp.1409-1412
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    • 2002
  • Polymeric membrane electrodes for acetate anion based on meso-(${\alpha}$,${\alpha}$,${\alpha}$,${\alpha}$)-5,10,15,20-tetrakis[2-(penta-fluorophenylurea) phenyl]porphyrin I and similar urea-functionalized porphyrins Ⅱ-Ⅳ as neutral ionophores were prepared. The membrane based on porphyrin I exhibits the best potentiometric properties in pH 6.0 rather than pH 7.0: linear stable response over a wide concentration range (6.0 ${\times}$$10^{-5}$-1.0 ${\times}$$10^{-2}$) with a slope of -59.6 mV/decade and a detection limit of log[CH3CO$O^-$] = -5.32. Selectivity coefficients obtained from the matched potential method (MPM) in pH 6.0 indicate that interferences of hydrophobic anions are very small for the membranes of porphyrins I and II having the strong withdrawing group. The electronic effect of urea-functionalized porphyrins and pH effect of buffer solutions are discussed on the potentiometric response.

단천환가감이 중풍 환자의 말초 단핵구에서 LPS 및 DFX 유도성 사이토카인 생성에 미치는 영향 (Effects of Danchunwhangagam on LPS or DFX-induced Cytokine Production in Peripheral Mononuclear Cells of Cerebral Infarction Patients)

  • 이성근;이기상
    • 동의생리병리학회지
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    • 제20권4호
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    • pp.929-935
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    • 2006
  • This study was to investigate the effect of Danchunwhangagam(DCWGG) extract on the production of proinflammatory cytokines in peripheral mononuclear cells (PBMCS) from Cerebral infarction(CI) patients. Methods: We examined that the inhibition rate of tumor necrosis factor $(TNF)-{\alpha},\;interleukin(IL)-1{\alpha},\;IL-1{\beta}$, IL-6, and IL-8 productions in DCWGG pretreatment PBMCs culture supernatant in the lipopolysaccaride(LPS)- or Oesferrioxamine(DFX)-treated cells compared to unstimulated cells. DCWGG inhibited the productions of $TNF-{\alpha},\;IL-1{\alpha},\;IL-1{\beta}$, IL-6, and IL-8 induced by LPS in a dose-dependent manner DCWGG might have regulatory effects on LPS or DFX-induced cytokine production, which might explain its beneficial effect in the treatment of CI.

Developmental Changes of the Alpha1-Adrenergic System in the Rat Heart

  • 한형미
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1993년도 제1회 추계심포지움 and 제2회 생리분자과학연구센터워크숍
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    • pp.25-27
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    • 1993
  • The effect of alpha$_1$-adrenergic stimulation on cardiac automaticity changes during myocardial development. To illustrate, in isolated tissues from the mature canine heart, alpha$_1$-adrenergic stimulation usually induces a decrease in automatic rate. On the other hand, many early neonatal fibers exhibit an increase in automatic rate In response to alpha$_1$-agonists, which is not seen in the adult.

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사람에서 식이의 n6 Gamma-Linolenic Acid와 n3 Alpha-Linolenic Acid가 혈장 지질조성과 혈소판 응집반응에 미치는 영향 (Effect of Dietary n6 Gamma-linolenic Acid and n3 Alpha-linolenic Acid on Plasma Lipid Composition and Platelet Aggregation in Human Subjects)

  • 박혜선
    • Journal of Nutrition and Health
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    • 제23권7호
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    • pp.477-491
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    • 1990
  • To observe the effect of dietary n6 linoleic acid, n6 gamma-linolenic acid and n3 alphalinolenic acid aon plasma lipid composition and platelet aggregation, twenty college women were divided into 4 groups and treated for 2 weeks with experimental diets supplying fat at 23% cal which were different only in fatty acid composition. Dietary fat was corn oil(CO) as a source of n6 linoleic acid(LA), perilla oil(PO) for n3 alpha-linolenic acid(ALA) and evenign primrose oil(EPO) for n6 gamma-linolenic acid(GLA). Plasma cholesterol level was slightly decreased by PL(13.5g) but significantly increased by equal amount of CO. However, there was similar hypocholeaterolemic effect when double amount of CO(27.0g), was supplemented. Therefore, total fat unsaturation may be more important factor for plasma cholesterol-lowering effect than the structure of fatty acid itself. Plasma cholesterol level was not lowered by supplement of GLA in CO diet. There was similar trend in hypotriglyceridemic effect by PO and CO as in plasma cholesterol. Plasma TG level was rather increased but not significantly by GLA supplement to CO diet. Overall, plasma lipid-lowering effect was greater by ALA than LA and GLA effect was not greater than by LA. GLA supplement did not significantly improve lipid compositions to prevent against CHD. There was no significant change both in fatty acid composition in platelet and ADP-induced platelet aggregation by GLA supplement to corn oil diet and by ALA in PO diet in young women.

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에스트로젠 수용체알파에 의한 Hypoxia Inducible Factor-1의 전사 활성조절 (Activation of Hypoxia Inducible Factor-1 Alpha by Estrogen Receptor Alpha)

  • 유광희;이영주
    • 약학회지
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    • 제54권2호
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    • pp.102-105
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    • 2010
  • Our previous results showed that hypoxia inducible factor-1 (HIF-1) activated estrogen receptor (ER) in the absence of ligand. In this study, we have studied the effect ER overexpression on the activation of HIF-1. ER overexpression induced transcription activation of hypoxia response element driven luciferase and vascular endothelial growth factor. As a negative control, the effect of ER on androgen receptor response element was used. Our result indicate that the two ER$\alpha$ and HIF-1 signaling pathways shares part of the activation pathway.

Aspergillus phoenicis를 이용한 Steroid의 변형에 관한 연구 -반응 온도와 초음파 처리의 효과- (Steroid Modification with Aspergillus phoenicis -Effects of Reaction Temperature and Sonication-)

  • 김말남;이영종;이형환
    • 한국균학회지
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    • 제13권2호
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    • pp.83-87
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    • 1985
  • A. phoenicis는 고온에서도 높은 lactose hydrolysis에 대한 효소 반응 활성을 가지고 있으나, 이 균주에 의한 progesterone의 전환 반응은 반응 온도에 매우 민감한 것으로 나타났다. 균체 내외부의 반응액 조성을 sonication 방법을 이용하여 조사함 결과 반응 초기에 균체의 내부에는 외부에 비하여 $11{\alpha}-hydroxyprogesterone$이 더 높은 농도로 존재하였으나 반응이 진행됨에 따라 균체 내부의 $11{\alpha}-hydroxyprogesterone$이 다른 생성물로 전환되어 오히려 더 낮은 농도의 $11{\alpha}-hydroxyprogesterone$이 존재하였다. A. phoenicis mycelium은 유기용매가 존재하는 반응액내에서도 새로운 액체 배지가 연속적으로 공급될 경우 물질대사를 계속 진행시킬 수 있으며, mycelium의 성장을 저해하지 않는 방법으로 고정된 cell을 이용하여 고정층 반응기에서 연속적으로 A. phoenicis-hydroxyprogesterone을 생산할 수 있다고 판단된다.

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Opposing Effects of Arkadia and Smurf on TGFβ1-induced IgA Isotype Expression

  • Choi, Seo-Hyun;Seo, Goo-Young;Nam, Eun-Hee;Jeon, Seong-Hyun;Kim, Hyun-A;Park, Jae-Bong;Kim, Pyeung-Hyeun
    • Molecules and Cells
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    • 제24권2호
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    • pp.283-287
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    • 2007
  • $TGF-{\beta}1$ induces Ig germ-line ${\alpha}$ ($GL{\alpha}$) transcription and subsequent class switching recombination (CSR) to IgA. In the present study, we investigated the roles of two E3-ubiquitin ligases, Smurfs (HECT type) and Arkadia (RING finger type) on $TGF{\beta}1$-induced IgA CSR. We found that over-expression of Smurf1 and Smurf2 decreased $TGF{\beta}1$-induced $GL{\alpha}$ promoter activity and strengthened the inhibitory effect of Smad7 on the promoter activity. Further, over-expression of Smurf1 and Smurf2 decreased both Smad3/4-mediated and Runx3-mediated $GL{\alpha}$ promoter activities, suggesting that the Smurfs can down-regulate the major $TGF-{\beta}1$ signaling pathway and decrease $GL{\alpha}$ gene expression. In parallel, the over-expressed Smurf1 decreased the expression of endogenous IgA CSR-predictive transcripts ($GLT_{\alpha}$, $PST_{\alpha}$, and $CT_{\alpha}$) and also $TGF{\beta}1$-induced IgA secretion. Conversely over-expression of Arkadia abolished the inhibitory effect of Smad7 on $TGF{\beta}1$-induced $GLT_{\alpha}$ expression and IgA secretion. Similar results were obtained in the presence of over-expressed Smad7 and Smurf1. These results indicate that Arkadia can amplify $TGF{\beta}1$-induced IgA CSR by degrading Smad7, which interacts with Smurf1. We conclude that Smurf and Arkadia have opposite roles in the regulation of $TGF{\beta}1$-induced IgA isotype expression.