• Maxillofacial Plastic and Reconstructive Surgery
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• 제11권1호
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• pp.187-202
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• 1989

This study was undertaken to investigate the effect of indomethacin on prostaglandins in 4-Nitroquinoline-N-Oxide (4-NQO) induced palatal carcinoma of albino rats. 128 Sprague-Dawley strain albino rats-about 100g in body weight-were used in this study, divided into as belows; 1. Normal group (16-albino rats) with no treatment, 2. Control group (16-albino rats) treated with prophylene application onto palatal mucosa 3 times a week. 3. Experimental group I (48-albino rats) treated with 0.5% 4-NQO in prophylene application onto palatal mucosa 3 times a week. 4. Experimental group II (48-albino rats) treated with 0.5% 4-NQO in prophylene application with administered $20{\mu}g/ml$ of indomethacin in drinking water ad. lib. Four animals were sacrificed 7th, 13th, 19th, and 25th week respectively in normal and control group, and 7th, 9th, 11th, 13th, 15th, 17th, 19th, 21st, 23rd, 25th, 27th and 29th week respectively in experimental group I and II at each time. The palatal and lingual tissues were excised and kept frozen at $-70^{\circ}C$. Densitometer scan and Beta-counting counter were used for the thin layer chromatography of the arachidonic acid metabolites. The obtained results were as belows; 1. In normal and control group, there was little change of the arachidonic acid metabolites during experiment period, and the tissue homogenates included prostaglandin $D_2$, 6-keto-prostaglandin $F_{1{\alpha}}$, prostaglandin $E_2$, thromboxane $B_2$, prostaglandin $F_{2{\alpha}}$ in that order of relative abundances. 2. In experimental group I, prostaglandin $D_2$, and prostaglandin $E_2$ were increased, while 6-keto-prostaglandin $F_{1{\alpha}}$ and thromboxane $B_2$ were decreased in relative abundances of arachidonic acid metabolites. And there was little change in prostaglandin $F_{1{\alpha}}$ 3. In experimental group II, prostaglandin $D_2$, and prostaglandin $E_2$ were increased, while 6-keto-prostaglandin $F_{1{\alpha}}$ and thromboxane $B_2$ were decreased in relative abundances of arachidonic acid metabolites. And there was little change in prostaglandin $F_{2{\alpha}}$ also. 4. In the range of increase in prostaglandin $D_2$, and prostaglandin $E_2$, and that of decrease in 6-keto-prostaglandin $F_{1{\alpha}}$ and thromboxane $B_2$, in relative abundances, there was wider in experimental group I than in group II. 5. In the range of increase in prostaglandin $D_2$, and prostaglandin $E_2$, and that of decrease in 6-keto-prostaglandin $F_{1{\alpha}}$ and thromboxane $B_2$, in relative abundances, there was wider in palatal mucosa than in lingual mucosa in experimental group I and II.

• 통합자연과학논문집
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• 제8권1호
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• pp.75-79
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• 2015

Thromboxane A2 receptors (TXA2-R) are the G protein coupled receptors localized on cell membranes and intracellular structures and play pathophysiological role in various thrombosis/hemostasis, modulation of the immune response, acute myocardial infarction, inflammatory lung disease, hypertension and nephrotic disease. TXA2 receptor antagonists have been evaluated as potential therapeutic agents for asthma, thrombosis and hypertension. The role of TXA2 in wide spectrum of diseases makes this as an important drug target. Hence in the present study, homology modeling of TXA2 receptor was performed using the crystal structure of squid rhodopsin and night blindness causing G90D rhodopsin. 20 models were generated using single and multiple templates based approaches and the best model was selected based on the validation result. We found that multiple template based approach have given better accuracy. The generated structures can be used in future for further binding site and docking analysis.

• Molecular & Cellular Toxicology
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• 제4권1호
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• pp.72-77
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• 2008

The present study was undertaken to determine whether pioglitazone treatment influences on the agonist-induced vascular smooth muscle contraction and, if so, to investigate the related mechanism. The measurement of isometric contractions using a computerized data acquisition system was combined with molecular experiments. Pioglitazone decreased Rho-kinase activating agonist-induced contraction but not phorbol ester-induced contraction suggesting the least involvement of $Ca^{2+}$-independent thin filament regulation of contractility. Furthermore, pioglitazone decreased thromboxane $A_2$ mimeticinduced phosphorylation of MYPT1 at Thr855, the newly-highlighted site, instead of Thr696. In conclusion, this study provides the evidence and possible related mechanism concerning the vasorelaxing effect of pioglitazone as an antihypertensive on the agonist-induced contraction in rat aortic rings regardless of endothelial function.

• 약학회지
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• 제41권3호
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• pp.298-304
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• 1997

Molecular mechanics and conformation search methods were carried oyt to investigate the relationship between conformations and thromboxane synthetase ingibitory activities of om ega-pyridylalkenoic acids. The initial geometries of ${\omega}$-pyridylalkenoic acids and heme part of cytochrome P-450 were obtained from MM+ geometry optimization. The bond lenths and angles were not varied by step during the conformation searching. Stable conformers of some ${\omega}$-pyridylalkenoic acids were obtained by comformational search method. The distances were 8.5~10.8 ${\AA}$- between N atom at 3-position of pyridine ring and C atom at carboxylic group of stable ${\omega}$-pyridylalkenoic acids. The conformations of ${\omega}$-pyridylalkenoic acids and heme part complex were determined by same method. In theses structures, benzene ring and ethylene group in ${\omega}$-pyridylalkenoic acids are making the structure more rigid and increase inhbitory activity. The electron donating groups in C atom shich is connected to pyridine ring also increase activity.

• 약학회지
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• 제56권3호
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• pp.180-185
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• 2012

The aim of present study was to investigate the possible influence and related mechanism of alcohol on the arterial contraction. Vascular contraction involves the activation of thick or thin filament pathway. However, there are no reports addressing the question whether this pathway is involved in alcohol-induced regulation. We hypothesized that alcohol plays a role in vascular contraction evoked by a vasoconstrictor in rat aortae regardless of endothelial function. Denuded arterial rings from male rats were used and isometric contractions were recorded using a computerized data acquisition system. Interestingly, alcohol at a low concentration (3% v/v) inhibited thromboxane $A_2$ or phorbol ester-induced contraction with endothelial function but at a high concentration (10%) didn't inhibit and rather increased the contraction in the denuded muscle. Therefore, alcohol at a low concentration decreases the contraction and alcohol at a high concentration increases the contraction suggesting that additional pathways different from endothelial nitric oxide synthesis might be involved in the regulation of contractility. In conclusion, alcohol has some effect on the regulation of contractility regardless of endothelial function.

• 약학회지
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• 제58권5호
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• pp.337-342
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• 2014

The present study was undertaken to investigate the influence of diosgenin on vascular smooth muscle contractility and to determine the mechanism involved. We hypothesized that diosgenin, the primary ingredient of Dioscorea villosa, plays a role in vascular relaxation through inhibition of Rho-kinase in rat aortae. Denuded arterial rings from male Sprague-Dawley rats were used and isometric tensions were recorded using a computerized data acquisition system. Interestingly, diosgenin inhibited fluoride-induced contraction but didn't inhibit phorbol ester-induced contraction suggesting that additional pathways different from endothelial nitric oxide synthesis such as inhibition of Rho-kinase might be involved in the vasorelaxation. Furthermore, diosgenin didn't inhibit thromboxane $A_2$-induced increases in pERK1/2 levels suggesting the mechanism excluding inhibition of thromboxane $A_2$-induced increases in ERK1/2 phosphorylation. This study provides evidence that diosgenin induces vascular relaxation through inhibition of Rho-kinase in rat aortae.

• 생약학회지
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• 제51권4호
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• pp.231-237
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• 2020

Euchrestaflavanone B (EFB) is a flavonoid that can be found in root bark, particularly in Cudrania tricuspidata (C. tricuspidata). The extract of C. tricuspidata is widespread throughout Asia and used in traditional medicine. In a previous study, we found anti-platelet effects of substances isolated from C. tricuspidata on collagen-induced human platelets. However, the C. tricuspidata still contains numerous substances, thus, we have searched new candidate, EFB isolated from C. tricuspidata for anti-platelet effect. Our results showed that EFA inhibited collagen-induced platelet aggregation and glycoprotein IIb/IIIa (αIIb/β3)-mediated signaling events, including platelet adhesion, granule secretion, thromboxane A2 production and clot retraction. These results suggest that EFA has inhibitory effects on human platelet activities and thrombus formation and has potential value as a natural substance for preventing platelet-induced thrombosis.

• 한국영양학회:학술대회논문집
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• 한국영양학회 1997년도 추계학술대회 초록
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• pp.42-42
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• 1997

• 한국영양학회:학술대회논문집
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• 한국영양학회 1996년도 추계학술대회 초록
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• pp.56-56
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• 1996

• 대한약리학회지
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• 제20권1호
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• pp.41-46
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• 1984

카드뮴중독으로 혈소판응집이 항진되어 고혈압 또는 동맥경화증이 발생한다는 연구보고를 감안하여 가토와 흰쥐의 생체내 실험으로서 미세혈전의 형성, Malondialdehyde(MDA) 및 thromboxane $B_2(TXB_2)$치에 미치는 카드뮴의 효과를 검토하고, in vitro실험으로 카드뮴을 처치한 가토 대동맥절편이 혈소판응집에 미치는 영향을 관찰하였으며, prostacyclin의 합성능력을 측정하여 그 결과를 다음과 같이 요약하였다. 1)Cadmium chloride 2mg/kg을 매주 동물의 복강내에 주입하였을 때 미세혈전형성이 증가되었다. 2) 카드뮴 중독동물의 platelet-rich plasma (PRP)는 MDA와 $TXB_2$형성이 정상동물에서 보다 현저히 증가되었다. 3) 카드뮴을 중독시킨 가토의 platelet-poor plasma (PPP)에서의 lipid peroxide치는 대조군과 차이가 없었다. 4) In vitro 실험으로, 가토대동맥 절편에서의 6-keto-$PGF_{1{\alpha}}$의 생성은 카드뮴 농도에 비례하여 억제되었고 이때 혈소판 응집률의 증가와 평행하였다. 5) 이상의 결과로서 카드뮴은 동맥내피세포에서 prostacyclin 합성을 억제할 뿐만 아니라 혈소판에서 $TXA_2$합성을 촉진시켜 그 결과로 혈소판 응집률을 증가시켰음을 알 수 있었다.