• Biomolecules & Therapeutics
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• v.3 no.2
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• pp.104-110
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• 1995

Arachidonic acid (AA, C20 : 4, $\omega$-6) and eicosapentanoic acid (EPA,C20 : 5, $\omega$-3), which are polyunsaturated fatty acids forming eicosanoids, were tested for their effects on blood pressure in Wistar rats and SHR. AA is the most important precursor for the biosynthesis of eicosanoids which include the prostaglandins, prostacyclin (PGI$_2$), thromboxane $A_2$ (TXA$_2$) and the leukotriens. TXA$_2$is a potent vasoconstrictor and a powerful inducer of platelet aggregation causing myocardial infarction and hypertention. In contrast, PGI$_2$ induces vasodilation and inhibits platelet aggregation. In this study, AA markedly increased blood pressure, but its effect was antagonized by both EPA, a structural analog of AA, and dazmegrel, a TX synthetase inhibitor. Also, AA enhanced the antihypertensive effects of hydralazine and captopril, and EPA reduced TXA$_2$ production. These results indicate that the hypotensive effects of EPA might be closely related to the decrease in TXA$_2$ biosynthesis due to competitive inhibition by structural similarity of the EPA to the AA, the precursor of TXA$_2$.

• The Korean Journal of Zoology
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• v.34 no.2
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• pp.142-147
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• 1991

Angiotensin I-converting enzyme (ACE) activity has been characterized in the rice eel, Monopterus albus. Peak activity of ACE in plasma from the rice eel was shown at around pH 10, which was more alkaline compared to that of mammals. Chloride requirements for the optimal ACE activity were different from species to spedes. ACE inhibitors, EDTA, teprotide (SQ 20, 881), and captopril (SQ 14, 225) showed dose-dependent inhibitions of ACE activity in plasma from the rice eel as well as mammals. ACE activity in the rice eel was increased by CoCI2, and the enzyme activity was more unstable at high temperature as compared to mammals The highest activity of ACE among the various tissues in the rice eel was found in the brain.

• YAKHAK HOEJI
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• v.43 no.6
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• pp.843-850
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• 1999

We investigated whether endothelium-derived NO and endothelin-1 might result enhanced vasoconstriction induced by administration of norepinephrien (NE) at the early stage of one-kidney, one-clip (1K1C) renal hypertensive rats. We also studied the relation ship of renin-angiotensin system (RAS) using rat aorta in this hypothesis. L-NMMA (30$\mu$M) and L-NAME(30${\mu}M$) enhanced vasoconstriction induced by NE in thoracic aorta of control rats. However angiotensin converting enzyme (ACE) inhibitor didn't. The aorta of 1KIC rats showed a singnificantly exaggerated contractile response to NE as compared with control rats. Rub-bing the endothelium abolished this difference. Ach and SNP-induced vasorelaxation show no significant difference between 1KIC and control rats. The treatment of phosphoramidon (10${\mu}M$) and oral administration of captopril (0.05, w/v%) abolished the exaggerated contractile response to NE at early stage of 1KIC rats. These results suggest that the increase of contractile response at the early phase in 1KIC rat is partially involved in the activation of ACE.

• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.375-383
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• 2014

This study aimed to investigate the effects of 50% ethanol extract of ripe black raspberry (Rubus occidentalis, RBR) on hypertension in human umbilical vein endothelial cells (HUVECs) and in spontaneously hypertensive rats (SHR). Angiotensin converting enzyme (ACE) inhibition and activation of nitric oxide production by endothelial nitric oxide synthase were significantly regulated by RBR in HUVEC cells. Moreover, the SHR showed significantly higher levels of blood pressure, ACE, renin, endothelin-1, and interleukin-6 than Wistar Kyoto rats (WKY). However, treatment with captopril and RBR decreased the levels of these hypertension-related events in the SHR. The renal arteriole showed greater media thickness/lumen diameter (%) in the SHR than in the WKY. However, media thickness/lumen diameter (%) was reduced in SHR by treatment with captopril and RBR. In addition, the number of eosinophilic cardiac muscle cells was decreased in the heart muscles after treatment with captopril and RBR. Therefore, this study suggests that 50% ethanol extract of RBR may be useful for the prevention and treatment of high blood pressure.

• Korean Journal of Microbiology
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• v.55 no.2
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• pp.143-148
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• 2019

The synthesis of captopril as an important chiral drug in commerce needs expensive resolution process of racemic mixture. Microorganisms, producing a thermostable esterase that catalyzes the stereo-selective hydrolysis of methyl DL-${\beta}$-acetylthioisobutyrate (DL-ester) to D-${\beta}$-acetylthioisobutyric acid (DAT) were screened from soils. Among the strains tested, strain No CJ-317 and strain No CJ-187 with highest activity were selected as the best DAT producer. The newly isolated microorganisms were identified respectively, as Klebsiella pneumoniae and Pseudomonas putida. The cell activity of esterase from K. pneumoniae CJ-317 and P. putida CJ-187 were showed an optimal reaction activity at $75^{\circ}C$ and $60^{\circ}C$, respectively. Also the cell activity of K. pneumoniae CJ-317 was stable up to $80^{\circ}C$ for 1 h, while that of P. putida CJ-187 was not over $60^{\circ}C$. By varying the concentration of DAT in the reaction mixture, the cell activity of P. putida CJ-187 showed about 55% and 80% of product inhibition in the presence of 2.5% (w/v) and 5.0% of DAT respectively. K. pneumoniae CJ-317 had less product inhibition than P. putida CJ-187 by about 35% and 44% at the same concentrations respectively. The esterase of newly isolated K. pneumoniae CJ-317 could be useful for the stereo-selective hydrolysis of DL-ester to DAT.

• 대한핵의학회:학술대회논문집
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• 2000.05a
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• pp.56-56
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• 2000

• Journal of Acupuncture Research
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• v.19 no.4
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• pp.152-166
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• 2002

Objective : This study was undertaken to determine whether Hominis Placenta(HP) aqua-acupuncture exerts renoprotective effect on diabetic nephropathy induced by streptozotocin(STZ) in rats. Methods : In order to study the renoprotective effect of HP aqua-acupuncture, experimental animals were divided into 5 groups and treated for 2 weeks as follows: control group was injected subcutaneously by saline aqua-acupuncture into Sinsu(BL23) in STZ induced diabetic rats, 5% HP aqua-acupuncture group was injected subcutaneously by 5% HP aqua-acupuncture into Sinsu(BL23) in STZ induced diabetic rats, 10% HP aqua-acupuncture group was injected subcutaneously by 10% HP aqua-acupuncture into Sinsu(BL23) in STZ induced diabetic rats, normal group was injected subcutaneously by saline aqua-acupuncture into Sinsu(BL23) in normal rats, and Captopril group was administrated with captopril at a dose of 50mg/kg in STZ induced diabetic rats. Results : While HP aqua-acupuncture did not reduce any body weight, index of kidney hypertrophy, the plasma glucose concentration and BUN respectively, HP aqua-acupuncture showed lowering urinary albumin excretion rate and serum creatinine as compared with the control group. Gene and protein expressions of $TGF-{\beta}1$ and fibronectin in kidney, one of the extracellular matrix proteins were investigated. There were significant differences in expression levels in HP aqua-acupuncture group as compared with the control group, and $100{\mu}g/m{\ell}$ and $500{\mu}g/m{\ell}$ of HP depressed apoptosis, showing in a dose dependent manner. In the HE staining, HP aqua-acupuncture inhibited the injury of glomerulus and proximal convoluted tubule. Conclusions : HP aqua-acupuncture showed the renoprotective effect possibly through suppressions of $TGF-{\beta}1$ and fibronectin expressions in kidney.

• The Journal of Internal Korean Medicine
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• v.25 no.4
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• pp.9-17
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• 2004

Objective : Mesangial cell proliferation and excessive accumulation of extracellular matrix (ECM) proteins is the common pathologic feature of glomerulosclerosis, and platelet-derived growth factor (PDGF) BB-chain, transforming growth factor betal $(TGF-{\beta}1)$, cyclin dependent kinases (CDK) and CDK inhibitors mediated in these pathophysiological processes. Bupleurum falcatum which is one of the most widely used components in traditional oriental medicines, has multiple pharmacological effects, such as antipyretic, analgesic, immune modulating, anti-inflammatory, anti-allergic, anti-thrombotic, anti-atherosclerotic, and antitussive effects. Methods : In this study, we evaluated the influence of Bupleurum falcatum on mesangial cell proliferation, DNA synthesis and expression of PDGF-BB chain, $TGF-{\beta}1$, CDKI, CDK2, CDK4, p21 and p27 in fetal bovine serum (FBS)-activated human mesangial cell. Results : Bupleurum falcatum reduced the mesangial cell proliferation and DNA synthesis more than control and captopril. And in the ELISA analysis of $TGF-{\beta}1$, and RT-PCR of PDGF-BB chain, CDK1, CDK2, CDK4, p21, and p27, Bupleurum falcatum inhibited the expression of $TGF-{\beta}1$ protein and PDGF-BB, CDK1, CDK2 gene and promoted that of p21 gene in a dose-dependent manner in comparing with control and captopril. Conclusions: These results suggest that Bupleurum falcatum may inhibit the mesangial cell proliferation and DNA synthesis by regulation of PDGF-BB and $TGF-{\beta}1$ expressions, and by modulation of CDK1, CDK2 and p21 expression.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1476-1479
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• 1998

Effect of chitosan oligosaccharides on the ACE (angiotensin I converting enzyme) inhibition and antihypertension in SHR (Spontaneously hypertensive rat) was examined. The ACE inhibition activity was observed in all the chitosan oligosaccharides used in this study, and chitosan trimer exhibited the highest inhibitory activity $(IC_{50}=0.9{\mu}M)$ compared with other chitosan oligosaccharides $(IC_{50}\;:\;2.4{\sim}100\;{\mu}M)$. The results suggested that chitosan trimer was a good inhibitor of ACE in molecular level. When the single oral dose (2.14 mg/kg, similar to dose level of Captopril, known as strong ACE inhibitor) of chitosan trimer was given to 8 or 21 week aged SHR, the blood pressure reduction of both SHRs in 4hrs were $27{\pm}4.8\;mmHg\;and\;36{\pm}4.3\;mmHg$, respectively. Therefore, it was suggested that chitosan trimer could be applicable as natural ACE inhibitor related to antihypertension.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1511-1516
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• 2007

To assess a potential possibility of Eucommia ulmoides (EU) as a functional food, anti-hypertensive materials of EU were isolated by silica gel column, thin layer and reverse phase column chromatographies, and then ACE (angiotensin-converting emzyme) inhibitory activities of different parts (leaf, bark, and stem) were investigated. The isolated compound, 8A, was pinoresinol-4,4'-di-O-${\beta}$-D-glucoside (below PDG) originating from Eucommial Cortex and its purity was 95.64%. Of all the samples tested, PDG in raw bark and roasted bark was the highest level at 135.13 mg% and 163.67 mg%, respectively. In ACE inhibitory activity at 10 mg/mL of EU extracts, roasted leaf, raw bark, and roasted bark were 77.56%, 75.73%, and 75.73%, respectively. ACE activities at 1 mg/mL were shown to be 91.87% for PDG, 97.06% for $Enalapril^{(R)}$, and 90.32% for $Captopril^{(R)}$.