• 제목/요약/키워드: inhibitory mechanism

검색결과 1,035건 처리시간 0.035초

고양이의 신장에서 Ethacrynic Acid가 PAH 분비에 미치는 영향 (Effect of Ethacrynic Acid on Renal Tubular Secretion of PAH in Anesthetized Cat)

  • 김용근;정진섭;김주헌;서덕준;이상호
    • The Korean Journal of Physiology
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    • 제16권2호
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    • pp.177-186
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    • 1982
  • The effect of ethacrynic acid (EA) on the renal secretion of PAH was examined in cat kidney. $C_{PAH}$ and $T_{PAH}$ were measured before and after infusion of EA $(0.5{\sim}50mg/kg)$ through the femoral vein. The following results were obtained: 1) In the dosage range of 0.5 to 25 mg/kg, EA increased the urine flow, and sodium and potassium excretion in dose-dependent manner, but the glomelular filtration rate was decreased as the dosage of EA was increased. 2) $C_{PAH}$ and $T_{PAH}$ were decreased by EA in the dosage range of 3 to 25 mg/kg and 1 to 50 mg/kg, respectively, in dose·dependent manner with the dosage to cause 50% inhibition of about 5 mg/kg. 3) With dosage of 0.5mg/kg, EA appeared to exert a great effect on diuretic response without the influence on $T_{PAH}$. At 10min after infusion of EA, a potent diuretic effect appeared, while $T_{PAH}$ did not show a significant change. These results suggest that the action mechanism of EA on tubular secretion of PAH may be different from that on natriuresis. 4) With dosage of 5 mg/kg, EA did not inhibit the Na-K-ATPase activity in microsomal fractions from both cortex and medulla. 5) The double reciprocal plot ($l/T_{PAH}$ versus $l/P_{PAH}$) suggested that EA inhibited the P AH secretion by a competitive pattern. However, probenecid, a prototypic inhibitor of the organic acid pump, had no influence on both the inhibitory effect of $T_{PAH}$ and the natriuretic effect by EA. These results suggest that in vivo EA altered tubular secretion of P AH through interactions with receptors that are not identical with the Na-K-ATPase.

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Surfactin Blocks NO Production in Lipopolysaccharide-activated Macrophages by Inhibiting $NF-{\kappa}B$ Activation

  • Byeon, Se-Eun;Lee, Yong-Gyu;Kim, Byung-Hun;Shen, Ting;Lee, Sang-Yeol;Park, Hwa-Jin;Park, Seung-Chun;Rhee, Man-Hee;Cho, Jae-Youl
    • Journal of Microbiology and Biotechnology
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    • 제18권12호
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    • pp.1984-1989
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    • 2008
  • Surfactin is a natural biosurfactant derived from Bacillus subtilis and has various biological activities such as anticancer, antiplatelet, and anti-inflammatory effects. In this study, the inhibitory mechanism of surfactin in NO production from macrophages was examined. Surfactin down regulated LPS-induced NO production in RAW264.7 cells and primary macrophages with $IC_{50}$ values of 31.6 and $22.4{\mu}M$, respectively. Immunoblotting analysis showed that surfactin strongly blocked the phosphorylation of IKK and $l{\kappa}B{\alpha}$ and the nuclear translocation of $NF-{\kappa}B$ (p65). Therefore, these data suggest that surfactin may act as a bacterium-derived anti-inflammatory agent with anti-$NF-{\kappa}B$ activity.

The Effect of Carbon Monoxide on Contraction, Cytosolic $Ca^{2+}$ Level and Ionic Currents in Guinea Pig Ileal Smooth Muscle

  • Kwon, Seong-Chun;Chung, Seung-Soo;Kim, Yun-Suk;Nam, Taick-Sang
    • The Korean Journal of Physiology and Pharmacology
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    • 제4권6호
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    • pp.479-486
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    • 2000
  • The aim of this study was to clarify the mechanism of the inhibitory action of carbon monoxide (CO) on contraction, by measuring cytosolic $Ca^{2+}$ level $([Ca^{2+}]_i)$ and ionic currents in guinea-pig ileum. CO (10%) inhibited 40 mM KCl-induced contraction and this effect was blocked by ODQ $(1\;{\mu}M),$ a soluble guanylyl cyclase (sGC) inhibitor. CO inhibited the 40 mM KCl-induced contraction without changing $[Ca^{2+}]_i.$ Cumulative addition of KCl induced a graded increase in $[Ca^{2+}]_i$ and muscle tension. In the presence of CO, cumulative addition of KCl induced smaller contraction than in the absence of CO. On the other hand, the increase in $[Ca^{2+}]_i$ induced by cumulative addition of KCl was only slightly decreased in the presence of CO, and the $[Ca^{2+}]_i-tension$ relationship shifted downwards. Using the patch clamp technique with a holding potential of -60 mV, we found that CO had little effect on the peak Ba currents $(I_{Ba})$ when voltage was stepped from -60 mV to 0 mV. In addition, CO showed no effect on the depolarization-activated outward $K^+$ currents in the all potential ranges. We conclude that CO inhibits smooth muscle contraction mainly by decreasing the $Ca^{2+}$ sensitivity of contractile elements via a cGMP-dependent pathway, not by involving L-type $Ca^{2+}$ and outward-potassium currents in guinea-pig ileum.

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Ginger and Its Pungent Constituents Non-Competitively Inhibit Serotonin Currents on Visceral Afferent Neurons

  • Jin, Zhenhua;Lee, Goeun;Kim, Sojin;Park, Cheung-Seog;Park, Yong Seek;Jin, Young-Ho
    • The Korean Journal of Physiology and Pharmacology
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    • 제18권2호
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    • pp.149-153
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    • 2014
  • Nausea and emesis are a major side effect and obstacle for chemotherapy in cancer patients. Employ of antiemetic drugs help to suppress chemotherapy-induced emesis in some patients but not all patients. Ginger, an herbal medicine, has been traditionally used to treat various kinds of diseases including gastrointestinal symptoms. Ginger is effective in alleviating nausea and emesis, particularly, for cytotoxic chemotherapy drug-induced emesis. Ginger-mediated antiemetic effect has been attributed to its pungent constituents-mediated inhibition of serotonin (5-HT) receptor activity but its cellular mechanism of action is still unclear. Emetogenic chemotherapy drugs increase 5-HT concentration and activate visceral vagal afferent nerve activity. Thus, 5-HT mediated vagal afferent activation is essential to provoke emesis during chemotherapy. In this experiment, water extract of ginger and its three major pungent constituent's effect on 5-HT-evoked responses were tested on acutely dispersed visceral afferent neurons with patch-clamp methods. The ginger extract has similar effects to antiemetic drug ondansetron by blocking 5-HT-evoked responses. Pungent constituents of the ginger, [6]-shogaol, [6]-gingerol, and zingerone inhibited 5-HT responses in a dose dependent manner. The order of inhibitory potency for these compounds were [6]-shogaol>[6]-gingerol>zingerone. Unlike well-known competitive 5-HT3 receptor antagonist ondansetron, all tested ginger constituents acted as non-competitive antagonist. Our results imply that ginger and its pungent constituents exert antiemetic effects by blocking 5-HT-induced emetic signal transmission in vagal afferent neurons.

α-Isocubebene modulates vascular tone by inhibiting myosin light chain phosphorylation in murine thoracic aorta

  • Ye, Byeong Hyeok;Kim, Eun Jung;Baek, Seung Eun;Choi, Young Whan;Park, So Youn;Kim, Chi Dae
    • The Korean Journal of Physiology and Pharmacology
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    • 제22권4호
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    • pp.437-445
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    • 2018
  • ${\alpha}$-Iso-cubebene (ICB) is a dibenzocyclooctadiene lignin contained in Schisandra chinensis (SC), a well-known medicinal herb that ameliorates cardiovascular symptoms, but the mechanism responsible for this activity has not been determined. To determine the role played by ICB on the regulation of vascular tone, we investigated the inhibitory effects of ICB on vascular contractile responses by adrenergic ${\alpha}$-receptor agonists. In addition, we investigated the role on myosin light chain (MLC) phosphorylation and cytosolic calcium concentration in vascular smooth muscle cells (VSMC). In aortic rings isolated from C57BL/6J mice, ICB significantly attenuated the contraction induced by phenylephrine (PE) and norepinephrine (NE), whereas ICB had no effects on KCl (60 mM)-induced contraction. In vasculatures precontracted with PE, ICB caused marked relaxation of aortic rings with or without endothelium, suggesting a direct effect on VSMC. In cultured rat VSMC, PE or NE increased MLC phosphorylation and increased cytosolic calcium levels. Both of these effects were significantly suppressed by ICB. In conclusion, our results showed that ICB regulated vascular tone by inhibiting MLC phosphorylation and calcium flux into VSMC, and suggest that ICB has anti-hypertensive properties and therapeutic potential for cardiovascular disorders related to vascular hypertension.

활혈화어법을 응용한 한방 항암처방 개발에 관한 연구 (Study of Developmental New Anti-cancer Prescription from Herbs of ‘the activation of blood and the elimination of blood stasis’)

  • 우원홍;김용수;전병훈;정우열
    • 동의생리병리학회지
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    • 제16권3호
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    • pp.409-420
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    • 2002
  • At once Medicine of East and West have the same purpose in treating, but there is a difference between the method of medical care and the view/slant on a disease each other. In the East Medicine, It is very difficult to explain the concept of Hwalhyulhwau but it is one of the way to cure cancer for long time. Be based on the theory of the East Medicine, research single medicine's anti-cancer effect among the natural products that has anti-cancer function. Moreover, for the purpose of finding new way to cure and prevent against cancer, we, the researchers, divided into four groups for this research: Group one: survey new substance with anti-cancer effects from natural products. Group two: research of anti-cancer mechanism through the experimental studies. Group three: research of immune responses in anti-canncer effects from natural products. Group four: research of the inhibitory effect on metastasis through the anti-angiogenesis. From the above results, we blended efficacious medidcines against cancer and made new prescriptions of Soam-I and Soam-II. Now, we are studying on these new prescriptions. We speculate that Soam-I and Soam-II may be used for a new conceptional anticancer therapy.

장원환가감방 수추출물(水抽出物)이 아밀로이드 전구단백질으로 유도된 생쥐의 신경아세포주에서의 항치매 효과 (Inhibitory effect of Alzheimer's in APP-induced Neuro 2A cells by JangWonHwanGagambang(JWHG) water extract)

  • 김상태;이종화;김태헌;손형진;한평림;강형원
    • 동의신경정신과학회지
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    • 제18권2호
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    • pp.13-24
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    • 2007
  • Objective : Recent studies indicate that the deposition of ${\beta}-amyloid$ ($A{\beta}$) is related in the pathogenesis of Alzheimer's disease (AD), but the underlying mechanism is still not clear. Method : To investigate the potential cellular functions of APP and water extract of the JangwonHwangagambang (JWHG), we use as in vitro model, neuro 2A cells were treated with either JWHG or its oriental medicines, and the effect in APP expression was determined by MTT and LDH assay. JWHG have been shown to be neuroprotective in different model systems. We asked whether JWHG treatment would influence cell survival and AD-like pathology in APP-induced neuronal cells. Result : JWHG and water extracts of some oriental medicine has attenuated high cell death in vitro. JWHG-treated cells increased percentage of cell survival more longly than controls. JWHG had significantly increas neurite outgrowth in the as compared to control cells. Conclusion : These results suggest that JWHG prevent APP-induced neurotoxicity through attenuating oxidative stress, and may be useful as potential therapeutic agents for AD.

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작약탕(芍藥湯) 물 추출물의 항염증작용에 관한 연구 (Study on the Anti-inflammatory Effect of Jakyak-tang Water Extract)

  • 서윤희;강옥화;권동렬;이장석;한종현;이기남;정명수
    • 동의생리병리학회지
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    • 제25권3호
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    • pp.503-509
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    • 2011
  • Jakyaktang(芍藥湯; JYT) exhibits potent anti-inflammatory activity in widely intestinal disease, but its mechanism was undisclosed. To elucidate the molecular mechanisms of JYT on pharmacological and biochemical actions in inflammation, we examined the effect of JYT on pro-inflammatory mediators in phorbol 12-myristate 13-acetate (PMA) plus A23187-induced mast cell and lipopolysaccharide (LPS)-stimulated macrophages. The investigation focused on whether JYT inhibited pro-inflammatory cytokines such as interleukin-6 (IL-6), interleukin-8 (IL-8), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) in PMA plus A23187- induced HMC-1 cells and inflammatory madiators such as nitric oxide (NO), TNF-${\alpha}$, IL-6, iNOS, COX-2 in LPS-stimulated RAW 264.7 cells. We found that JYT inhibited LPS-induced NO, TNF-${\alpha}$ and IL-6 productions as well as the expressions of iNOS and COX-2. These results suggest that JYT has inhibitory effects on mast cell-mediated and macropage-mediated inflammation.

Anti-obese related pharmacological effects of standard potato protein extracts on the 45%Kcal high fat diet supplied mice

  • Kang, Su-Jin;Song, Chang-Hyun;Kim, Jong-Kyu;Chun, Yoon-Seok;Han, Chang-Hyun;Lee, Young-Joon;Ku, Sae-Kwang
    • 대한예방한의학회지
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    • 제22권2호
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    • pp.77-107
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    • 2018
  • Objectives : In present study, therefore, possible beneficial pharmacological activities of standard potato protein extracts (SPE) were observed on the mild diabetic obese mice. Methods : After end of 12 weeks of continuous oral administrations of three different dosages of SPE 400, 200 and 100 mg/kg, or metformin 250 mg/kg, analyzed the hepatoprotective, hypolipidemic, hypoglycemic, nephroprotective and anti-obesity effects, separately. In addition, liver antioxidant defense systems were additionally measured with lipid metabolism-related genes expressions and hepatic glucose-regulating enzyme activities for action mechanism. Results : All of diabetes and related complications including obesity were significantly inhibited by treatment of SPE 400, 200 and 100 mg/kg, dose-dependently, and they also dramatically normalized the hepatic lipid peroxidation and depletion of liver endogenous antioxidant defense system, the changes of the hepatic glucose-regulating enzyme activities, also changes of the lipid metabolism-related genes expressions including hepatic $AMPK{\alpha}1$ and $AMPK{\alpha}2$ mRNA expressions, dose-dependently. Especially, SPE 200 mg/kg constantly showed favorable inhibitory activities against type II diabetes and related complications as comparable to those of metformin 250 mg/kg in HFD mice, respectively. Conclusions : The present work demonstrated that SPE 400, 200 and 100 mg/kg showed favorable anti-diabetic and related complications including obesity refinement activities in HFD mice, through AMPK upregulation mediated hepatic glucose enzyme activity and lipid metabolism-related genes expression, antioxidant defense system and pancreatic lipid digestion enzyme modulatory activities.

Curcumin Inhibits the Activation of Immunoglobulin E-Mediated Mast Cells and Passive Systemic Anaphylaxis in Mice by Reducing Serum Eicosanoid and Histamine Levels

  • Li, Xian;Lu, Yue;Jin, Ye;Son, Jong-Keun;Lee, Seung Ho;Chang, Hyeun Wook
    • Biomolecules & Therapeutics
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    • 제22권1호
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    • pp.27-34
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    • 2014
  • Curcumin is naturally occurring polyphenolic compound found in turmeric and has many pharmacological activities. The present study was undertaken to evaluate anti-allergic inflammatory activity of curcumin, and to investigate its inhibitory mechanisms in immunoglobulin E (IgE)/Ag-induced mouse bone marrow-derived mast cells (BMMCs) and in a mouse model of IgE/Ag-mediated passive systemic anaphylaxis (PSA). Curcumin inhibited cyclooxygenase-2 (COX-2) dependent prostaglandin $D_2$ ($PGD_2$) and 5-lipoxygenase (5-LO) dependent leukotriene $C_4$ ($LTC_4$) generation dose-dependently in BMMCs. To probe the mechanism involved, we assessed the effects of curcumin on the phosphorylation of Syk and its downstream signal molecules. Curcumin inhibited intracellular $Ca^{2+}$ influx via phospholipase $C{\gamma}1$ ($PLC{\gamma}1$) activation and the phosphorylation of mitogen-activated protein kinases (MAPKs) and the nuclear factor-${\kappa}B$ (NF-${\kappa}B$) pathway. Furthermore, the oral administration of curcumin significantly attenuated IgE/Ag-induced PSA, as determined by serum $LTC_4$, $PGD_2$, and histamine levels. Taken together, this study shows that curcumin offers a basis for drug development for the treatment of allergic inflammatory diseases.