• YAKHAK HOEJI
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• v.55 no.2
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• pp.138-144
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• 2011

The aim of present study was to investigate the possible influence and related mechanism of resveratrol on U-46619 (high concentration)-induced vasoconstriction. Agonist-induced vascular smooth muscle contractions involve the activation of thick or thin filament pathway. However, there are no reports addressing the question whether this pathway is involved in resveratrol-induced relaxation in rat aortae contracted with high U-46619. We hypothesized that MEK or Rho-kinase inhibition plays a role in vascular relaxation evoked by resveratrol in rat aortae. Endothelium-denuded arterial rings from male Sprague-Dawley rats were used and isometric contractions were recorded using a computerized data acquisition system. Resveratrol fully inhibited U-46619 in low concentration-induced contraction regardless of endothelial function. However, resveratrol partially decreased U-46619 in high concentration-induced contraction regardless of endothelial function. Interestingly, only in U-46619 (high concentration)-induced contraction, no significant decrease was observed in phospho-ERK1/2 levels and slight decrease in phospho-MYPT1 levels suggesting that additional pathways different from them or endothelial nitric oxide synthesis might be involved in the vasorelaxation. In conclusion, in high U-46619-contracted rat aortae, resveratrol showed relaxation response regardless of endothelial function significantly but slightly decreasing MYPT1 phosphorylation rather than ERK1/2 phosphorylation.

• Korean Journal of Digital Imaging in Medicine
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• v.13 no.2
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• pp.55-58
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• 2011

It is important to study using experimental animals for research about stroke. Magnetic Resonance Imaging(MRI) is avaluable diagnosticmethods for stroke diagnosis. The purpose of this research is to know the Magnetic Resonance Imaging(MRI) and histopathological characteristics findings after induction of photothrombotic cerebral infarction in rat brain. Male Sprague-Dawley rats were anesthetized, Rose Bengal dye(20 mg/kg) was intravenously injected. The right sensonrimotor cortex of rat brain was exposed to cold light of 7 mm diameter at a position of 1 mm anterior and 3.5 mm lateral to bregma for 20 min. The post-infarction effects were monitored by T1 weighted and T2 weighted images of brain MRI. Histopathological changes were observed after Hematoxylin & Eosin staining. The lesion appeared clearly high signal intensity area on T2 weighted images(the major axis $7.04{\pm}0.11$ mm, the minor axis $3.08{\pm}0.04$ mm) and also H&E staining was same result. In conclusion, MRI was avaluable diagnostic methods for diagnosis and serial changes of stroke.

• The Korean Journal of Food And Nutrition
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• v.9 no.2
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• pp.201-212
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• 1996

The purpose of this study was to find an effect of honey on the lipid metabolism of Sprague Dawley rats. All experimental rats were fed ad libitum, for seven weeks, 68% saccharide diet and 10% or 20% honey from acacia, sumac and miscelllaneous flower honey, respectively, and sucrose. The food efficiency ratio of rat taken diet with honey and high fructose of control group was increased in comparison with the control group. The concentration of cholesterol in serum of rats take총 diet with and high fructose of control group was more increased in comparison with the control and normal group. The concentration of H DL-cholesterol in serum of rats taken sumac honey was increased 57.0% in comparison with the control group, but the concentration of VLDL, LDL-cholesterol in serum of rats taken diet 10PA sumac honey was decreased 48.36% in comparison with the control group. The concentration of phospholipid in serum of rats taken diet with 20% acacia or 10% miscellaneous honey was increased 24.7, 16.25%, respectively, in comparison with the control group. The concentration of free fatty acid in serum of rats taken Inlet with sumac or miscellaneous honey and high fructose was increased in comparison with the comparison with the control group. The concentration supplemented diet with acasia honey was increase in comparison with the control group. The concentration of triglyceride in serum of rat was increased by feeding of honey. The concentration of triglyceride in liver was increased, but the level of phospholipid was decreased by feeding of honey.

• Journal of Korean Biological Nursing Science
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• v.10 no.1
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• pp.1-10
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• 2008

Purpose: The purpose of this study was to investigate the cerebral infarction size, antioxidant enzyme activities and lipid peroxidation changes after 6 weeks of dietary soybean protein intake in a rat focal brain ischemia model. Method: Weaning Sprague-Dawley rats were fed with either modified AIN-93G diet containing casein 20% (control), 20% soybean protein isolate-based diet (S20), or 40% of soybean protein isolate-based diet (S40) for 6 weeks. The animals were subject to right middle cerebral artery occlusion for 2 hr. After 24 hr of recirculation, the rats were sacrificed. Antioxidant enzymes activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) and thiobarbituric acid reactive substance (TBARS) level in the right brain were also measured. Result: There were no significant differences in the right cortical infarction volume, TBARS level, SOD and CAT activities among the three groups whereas the GPx activities of the S20 group were significantly higher than those of the control group (p=.02). Conclusion: Our results suggest that 20% of soybean protein may have a modulating effect on GPx and possibly have some protective effect against oxidative stress although it may enough to decrease cerebral infarction volume in rat focal brain ischemia model.

• YAKHAK HOEJI
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• v.54 no.5
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• pp.392-397
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• 2010

The aim of present study was to investigate the possible influence and related mechanism of additional alcohol on the flavonoid- induced arterial relaxation. Agonist-induced vascular smooth muscle contractions involve the activation of thick or thin filament pathway. However, there are no reports addressing the question whether this pathway is involved in quercetin-induced relaxation cotreated with alcohol in rat aortae contracted with phorbol ester, fluoride or thromboxane $A_2$ mimetic U-46619. We hypothesized that cotreated alcohol plays a role in vascular relaxation evoked by quercetin in rat aortae. Endothelium-denuded arterial rings from male Sprague-Dawley rats were used and isometric contractions were recorded using a computerized data acquisition system. Quercetin inhibited phorbol ester, fluoride or thromboxane $A_2$-induced contraction regardless of endothelial function. However, alcohol didn't decrease any agonist-induced contraction. Interestingly, only in thromboxane $A_2$-induced contraction, synergistic results were observed in aortae denuded and cotreated with quercetin and alcohol suggesting that additional pathways different from antioxidation or endothelial nitric oxide synthesis might be involved in the vasorelaxation. In conclusion, in the agonists-contracted rat aortae, quercetin and alcohol together showed synergistic response regardless of endothelial function in an agonist-dependent manner.

• Korean Journal of Oriental Medicine
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• v.9 no.2
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• pp.131-148
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• 2003

This study was performed to evaluate the acute oral toxicity of an oriental medical prescription for obesity treatment, SH21-B, in Sprague-Dawley rats and Beagle dogs. SH21-B was administered in rats at does of 0mg/kg, 2,000mg/kg, and 5,000mg/kg. And also SH21-B was administered in Beagle dogs at does of 150mg/kg, 300mg/kg, and 600mg/kg. The rats and dogs of both sexes were observed daily for 14 days after single oral administration. Two female rats, one administered at 2,000mg/kg and the other administered at 5,000mg/kg, died, but no dead animal was observed among male rats. Therefore LD50 in the female rat is observed to be 8,710mg/kg, and MLD(Minimum Lethal Dose) of the male rat is observed to be more than 5,000mg/kg. Among dogs, no dead animal was observed up to 600mg/kg and MLD is observed to be more than 600mg/kg.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2003.11a
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• pp.86-91
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• 2003

In this study, in order to examine whether salt and heat shock stress would alter or not contraction and relaxation of isolated rat aorta. Under anesthesia with sodium pentobarbital(50 mg Kg$^{-1}$ i.p.), male Sprague Dawley rats weighing 300-330 g were subjected to 0, heat shock combined salt stress, where as the sham group was left at modified Krebs-bicarbonate solution. To measure contractile response of vascular ring preparation isolated from rat was determined in organ bath and was recorded on physiograph connected to isometric transducer. And the strip was checked for expression of heat shock protein(Hsps) by means of western blotting. The combination group of heat and 50 mM NaCl group increased vascular contractility, and the heat and 150 mM NaCl group decreased vascular contractility for 5 hours, and then recovered for 8 hours compared to that of control. Expressin of Hsp 70 of vascular muscle of rat aorta more increased by combination of heat and NaCl treatment than those of single treatment of heat or NaCl treatment, and vascular Hsp 70 showed a little decrease at 8 hours compared at 5 hours. These result indicate that mixed environmental stress either increased or decreased in vascular contractility by combination of heat and NaCl concentration.

• Korean Journal of Veterinary Research
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• v.51 no.2
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• pp.159-164
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• 2011

Alcohol abuse and its medical and social consequences are a major health problem in many areas of the world. Korean red ginseng (KRG) has been traditionally used for the treatment of liver disease. This study was conducted to evaluate the hepatoprotective effects of KRG against hepatotoxicity in Sprague- Dawley rats treated with ethanol (EtOH). Administration of EtOH for 20 days induced significant changes in serum biochemical parameters (aspartate aminotransferase, alanine transaminase, and glucose) accompanied by histological changes in the liver tissue. Treatment with KRG prior to administration of EtOH inhibited the EtOH-induced biochemical and histological changes of the liver. In perfused rat livers, administration of EtOH caused an increase in lactate dehydrogenase (LDH) release into the perfusate and activated the pro-apoptotic Bax protein but inhibited the anti-apoptotic Bcl-2 protein. Pretreatment with KRG prior to administration of EtOH decreased the EtOH-induced LDH release and inhibition of Bcl-2 protein. These results suggest that KRG exerts anti-apoptotic effects and alleviated EtOH-induced liver injury in rats.

• Preventive Nutrition and Food Science
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• v.9 no.3
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• pp.245-252
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• 2004

This study investigated the effects of an ethanol extract of Allium monanthum MAX. (AME) on ethanol-induced hepatotoxicity in rat liver. Sprague-Dawley rats weighing 100～150 g, were divided into 5 groups; normal group (NOR), AME 200 mg/kg treated group (S1), ethanol (35%, 10 mL/kg) treated group (S2), AME 200 mg/kg and ethanol (35%, 10 mL/kg) treated group (S3) and AME 400 mg/kg and alcohol (35%, 10 mL/kg) treated group (S4). AME was fractionated by the following solvents: n-hexane, chloroform, EtOAC and n-BuOH. Antioxidant index of the n-BuOH fraction was 600 ppm, highest among fractions. The growth rate and feed efficiency ratio were decreased by ethanol, but gradually increased to the corresponding level of the normal group by administering AME. The serum ALT activities that were elevated by ethanol were significantly decreased by AME administration. It was also observed that the hepatic activities of SOD, catalase, xanthine oxidase and GSH-Px that were increased by ethanol were also markedly decreased in the AME treated group with compared to ETB. These results suggest that ethanol extracts of Allium monanthum MAX. may have a protective effect on ethanol-induced hepatotoxicity in rat liver.

• YAKHAK HOEJI
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• v.50 no.4
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• pp.293-299
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• 2006

The aim of present study was to investigate the possible influence of Rho-kinase inhibition on the plant-derived estrogen-like compounds-induced arterial relaxation. Agonist- or depolarization-induced vascular smooth muscle contractions involve the activation of Rho-kinase pathway. However there are no reports addressing the question whether this pathway is involved in genistein-or daidzein-induced vascular relaxation in rat aortae precontracted with phenylephrine or thromboxane $A_2$ mimetic U-46619. We hypothesized that Rho-kinase inhibition plays a role in vascular relaxation evoked by genistein or daidzein in rat aortae. Endothelium-intact and denuded arterial rings from male Sprague-Dawley rats were used and isometric contractions were recorded using a computerized data acquisition system. Genistein concentration-dependently inhibited phenylephrine or thromboxane $A_2-induced$ contraction regardless of endothelial function. Surprisingly, in the agonists-induced contraction, similar results were also observed in aortae treated with daidzein, the inactive congener for protein tyrosine kinase inhibition, suggesting that Rho-kinase might act upstream of tyrosine kinases in phenylephrine-induced contraction. In conclusion, in the agonists-precontracted rat aortae, genistein and daidzein showed similar relaxant response regardless of tyrosine kinase inhibition or endothelial function.