• 동의생리병리학회지
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• 제16권1호
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• pp.67-71
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• 2002

This study investigated the relaxation effects of Crataegi Fructus(CF, Crataegus pinnatifida Bunge) on the contraction evoked by phenylephrine in rabbit carotid artery, and also analyzes antioxidative status in vitro. CF revealed siginificant relaxation on phenylephrine-induced arterial contraction. It's relaxant effect statistically significant in both in the presence of endothelium and absence of endothelium, but statistically exerted more strong relaxation in the presence of endothelium. CF increased in vitro nitric oxide(NO) production in dose-dependent manner. Also, they reduced malondiaidehyde(MDA) concentrations, phosphatidyl choline-liposome(PCOOH) contents, linoleic acid-induced lipid peroxidation and exerted 1,1-diphenyl-2- picryl-hydrazyl(DPPH) radical scavenging effect, in vitro. These results indicate that Crataegi Fructus would be effective in relaxing arterial contraction and it's antioxidative effects may be involved in endothelium-dependent relaxation of artery via vascular protective properites.

• 대한수의학회지
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• 제34권3호
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• pp.471-478
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• 1994

Effects of histamine on the ruminal smooth muscle motility of cattle were investigated in the longitudinal and circular smooth muscle strips. In order to these experiments, specimens were obtained from 35 korean native cattles, 3-4 years old, in Kwang-ju area slaughterhouse. Smooth muscle strips of rumen were made from sample, and then measured the isometric contraction with physiograph in $37{^{\circ}C}$ organ bath. The results were as follows : 1. Histamine caused two different types of response(a contraction or a relaxation) on the smooth muscle of cattle rumen. These responses increased in dose dependant manner. 2. Pyrilamine($H_1$-receptor antagonist) completely blocked contraction in all the preparation and converted the response into relaxation. 3. Cimetidine($H_2$-receptor antagonist) completely blocked relaxation in all the preparation and converted the response into contraction. 4. The contraction induced by histamine($10^{-3}M$) was not Mocked by cholinergic, adrenergic blocker or hexamethonium. 5. The contraction induced by histamine($10^{-3}M$) was markedly inhibited in the $Ca^{2+}$ free(or EDTA 2Na) Kreb's solution and by verapamil.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 춘계학술대회
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• pp.398-401
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• 1997

The EMG signal of spinal cord injured patient is very feeble because that the information from central nervous system is not sufficiently transmitted to molter neuron or muscle fiber. Therefore the observer can not observe contraction and relaxation movement of muscle from the raw EMG signal. In this paper, we propose the muscle contraction and relaxation pattern analysis method of spinal cord injured patient whose EMG signal is composed of the sum of motor unit action potential train with additive white Gaussian noise and impulsive noise. From the EMG model, we denoise impulsive noise using median filter which is a kind of nonlinear filter and the output of median filter is transformed to wavelet transform domain for denoising additive white Gaussian noise using threshold level removal technique. As a result, we can obtain the clear contraction and relaxation pattern.

• Journal of applied mathematics & informatics
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• 제16권1_2호
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• pp.383-405
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• 2004

We study the incomprssible Navier Stokes equations for the flow inside contraction geometry. The governing equations are expressed in the vorticity-stream function formulations. A rectangular computational domain is arised by elliptic grid generation technique. The numerical solution is based on a technique of automatic numerical generation of acurvilinear coordinate system by transforming the governing equation into computational plane. The transformed equations are approximated using central differences and solved simultaneously by successive over relaxation iteration. The time dependent of the vorticity equation solved by using explicit marching procedure. We will apply the technique on several irregular-shapes.

• 대한수의학회지
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• 제34권3호
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• pp.479-486
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• 1994

Effects of catecholamines and the site of receptor of catecholamines were investigated in the longitudinal muscle of the rumen. In order to this experiment, specimens were obtained from 35 Korean Native Cattles, 2-3 years old, in the Kwang-ju area slaughterhouse. Longitudinal muscle strips of rumen were made from sample, and then measured the isometric contraction with physiograph in $37{^{\circ}C}$ organ bath. The results were summarized as follows. 1. 30% of all strips showed rhythmic contraction after short incubation time. 2. Relaxation produced by catecholamines in this preparations increased in a dose-dependant manner. 3. Isoproterenol(${\beta}$-agonist) caused relaxation, but phenylephrine(${\alpha}_1$-agonist) and xylazine(${\alpha}_2$-agonist) were unaffected. 4. The relaxation induced by epinephrine and norepinephrine were not affected by phentolamine(${\alpha}$-blocker) and prazosin(${\alpha}_1$-blocker), yohimbine(${\alpha}_2$-blocker). But propranolol(${\beta}$-antagonist) abolished the effect of catecholamines on relaxation. 5. It is concluded that catecholamines produced relaxation in the longitudinal muscle of rumen via the ${\beta}$-adrenoceptor.

• 한국임상수의학회지
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• 제30권1호
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• pp.27-31
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• 2013

We investigated the effects of Ponciri Fructus (PF) and Aurantii Fructus Immaturus (AI) on the cicular and longitudinal smooth muscle of rat gastric fundus. Methanol extracts of PF (PFM) and AI (AIM), water-fractions (PFW, AIW) and chloroform-fractions (PFC, AIC) of the extracts induced relaxation in the rat fundic circular muscle pre-contracted by U46619. All extracts showed relaxation without significant differences among the extracts. In the longitudinal smooth muscle, PFM and its water fraction, PFW, showed multiphasic effects, fast relaxation and rebound contraction followed by lasting relaxation. AIM and AIW showed diphasic effects, transient contraction followed by lasting relaxation. However, PFC and AIC induced only relaxation in the rat fundic longitudinal muscle contracted by U46619. PFM showed significantly more effective relaxation compared with PFW, AIM and AIW. Hesperidin, flavonoids known as common constituent of PF and AI and it's an aglycon, hesperetin, induced relaxation in both fundic circular and longitudinal smooth muscle pre-contracted by U46619. Poncirin, known as flavonoid content of PF showed also induced relaxation in the both circular and longitudinal smooth muscle pre-contracted by U46619. These results suggest that both PF and AI has relaxing effects on the gastric fundus smooth muscle and its effects might be caused by their flavonoids constituents.

• 대한약침학회지
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• 제6권3호
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• pp.49-55
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• 2003

This study was undertaken to define the effect of ChungSangSaWhaTang on the norepinephrine-induced arterial contraction and the mechanism of ChungSangSaWhaTang-induced relaxation. In order to investigate the effect of ChungSangSaWhaTang on contracted rabbit carotid arterial strips, transverse strips with intact or damaged endothelium were used for the experiment using organ bath. To analyze the mechanism of ChungSangSaWhaTang-induced relaxation, ChungSangSaWhaTang extract infused into contracted arterial strips induced by norepinephrine after treatment of indomethacin, $N_{\omega}$-nitro-L-arginine, or tetraethylammonium chloride. ChungSangSaWhaTang relax arterial strip with endothelium contracted by norepinephrine, but in the strips without endothelium, ChungSangSaWhaTang-induced relaxation was significantly inhibited. The endothelium-dependent relaxation induced by ChungSangSaWhaTang was decreased by the pretreatment of $N_{\omega}$-nitro-L-arginine, but it was not observed in the strips pretreated with indomethacin or tetraethylammonium chloride. We suggest that ChungSangSaWhaTang may inhibit agonist-induced contraction through the formation of nitric oxide in the vascular endothelial cells.

• Journal of Ginseng Research
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• 제34권4호
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• pp.314-320
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• 2010

The previous reports have showed that ginseng saponins, which are the active ingredients of Panax ginseng, cause the relaxation of artery that are contracted due to a various of hormones or potassium ($K^+$). Recently, we also showed that ginsenosides differentially regulate channel activity. The purpose of this study was to examine whether ginseng saponins affect contraction induced by $K^+$, serotonin (5-HT), or acetylcholine (Ach) in porcine coronary vessel. Treatment with concentrations of ginseng saponins caused a relaxation of 25 mM KCl-induced porcine coronary artery contraction. Also, ginseng saponin induced a significant dose-dependent relaxation of $3\;{\mu}M$ 5-HT-induced porcine coronary artery with the endothelium. In the porcine artery with the endothelium, ginseng saponins induced a relaxation by $3\;{\mu}M$ 5-HT in a concentration-dependent pattern. Ginseng saponins induced relaxation of both 25 mM KCl- and $3\;{\mu}M$ 5-HT-induced coronary artery contraction in the absence and presence of the endothelium. In contrast, treatment with $100\;{\mu}g/mL$ ginseng saponin did not induce relaxation in coronary artery contraction induced by Ach ($0.01\;{\mu}M$ to $30\;{\mu}M$) in the presence of the endothelium, but did cause significant relaxation of coronary artery contractions by Ach ($0.01\;{\mu}M$ to $30\;{\mu}M$) in the absence of the endothelium. These findings indicate that ginseng saponin (> $100\;{\mu}g/mL$) significantly inhibits porcine coronary artery contractions caused by $K^+$, 5-HT, and Ach. Therefore, in this study, we demonstrated that ginseng saponin may show beneficial roles on abnormal coronary contraction.

• 동의생리병리학회지
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• 제16권1호
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• pp.62-66
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• 2002

Hypertension is not only a well-established cardiovascular risk factor but also increase the risk of atherosclerosis. Most studies conducted to investigate the effectiveness of treatment for cardiovascular disease such as hypertension have focused primarily on conventional drug and physiotherapeutic treatments. BanhabackchulChunma-tang(半夏白朮天麻湯:BCT) is popular herbal medicine used in clinic for the treatment of various symptoms of drulatory disorders and weakness of digestive system, including anorexa and nausea with vertigo, severe headache, vomiting and so on. However, the mechanisms underlying its efficacy are unknown. This study investigated the effects of BCT as an alternative medication on the contraction induced by phenylephrine and KCI in rat thoratic aorta. BCT revealed siginificant relaxation on phenylephrine-induced arterial contraction, but revealed noncompetitive effect on concentration responses of phenylephrine-induced contraction. Treatment of N-L/sup ω/ -argine methyl ester(L-NAME) and methylene blue(MB)(10/sup -5/M) reduced the relaxation of BCT. BCT also increased in vitro NO production. It suggest that the relaxation effect of BBT is related with NO pathway, becausse the effect of L-NAME and MB are due to inhibition of NO synthesis from endothelial cells. These results indicate that BCT would be effective in hypertension treatment and its mechanism of relaxtion on arterial contraction is likely to be related with NO production, blocking of α-receptor and signal transduction after receptor activation.

• 한국수산과학회지
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• 제47권2호
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• pp.122-128
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• 2014

The present study was performed to examine the contraction and relaxation responses of the smooth muscles, and search for antimicrobial and antioxidant activities in the tissues, of the starfish Asterina pectinifera. Frozen samples were extracted with distilled water containing 1% acetic acid. Extracts from all tissues showed potent antimicrobial activity against Escherichia coli D31. Relatively high levels of antimicrobial activity were also detected in the body extracts. Liver, tube feet, and body extracts caused contraction responses in the dorsal retractor muscles (DRM) of the starfish. In contrast, all tissues examined exhibited contractile activity in the esophagus of squid Todarodes pacificus. In addition, liver and gonad extracts caused contraction responses upon application to the intestine of the puffer fish Takifugu pardalis. Relaxation effects on the DRM of starfish were identified in most of the extracts, while no relaxant activity was detected in body extracts. Extracts from all tissues examined also exhibited antioxidant activities. The results of this study suggest that starfish are a potential source of novel bioactive compounds.