• The Korean Journal of Physiology
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• v.19 no.2
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• pp.189-202
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• 1985

Enhanced activity of renin-angiotensin-aldosterone system has been suggested as a cause of the high blood pressure in certain forms of experimental hypertension. In spontaneously hypertensive rats, however, increased activity of the system has not been found, and even suppressed renin angiotensin system has been reported in the spontaneously hypertensive rat. In the present experiments it was attempted to explore the possible alteration of the short loop negative feedback control in the hypertensive rat. Experiments have been done in the anesthetized spontaneously hypertensive rats(SHR) as well as in normotensive Wistar and Sprague Dawley rats as control. Responses of the plasma renin activity to the intravenous L-isoproterenol were dose dependent, in both SHR and normotensive control rats. Hypotensive responses to smaller do sea of L-isoproterenol were more accentuated in SHR than in the normotensive control rats. Angiotensin If given intravenously suppressed plasma renin activity in a dose dependent fashion in both groups. However, these suppressive responses were significantly attenuated in SHR as compared with the normotensive control rats. Treatment with angiotensin I-converting enzyme inhibitor did not correct the attenuated responses of the plasma renin activity to angiotensin II in SHR. Intravenous infusion of arginine vasopressin also produced a dose-dependent suppression of plasma renin activity in both groups. The responses to arginine vasopressin were also significantly attenuated to the normotensive control rats. In the sodium-depleted SHR, arginine vasopressin did not suppress plasma renin activity, whereas the suppressive responses to arginine vasopressin in the normotensive control rats were not different from the untreated control rats. These data suggest that there may be a derangement in the short loop negative feedback control of the renin-angiotensin system in spontaneously hypertensive rat.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.5
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• pp.416-423
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• 1993

Fish sauces prepared from sardine, Sardinops melanosticta were tested for inhibitory activity against angiotensin-I converting enzyme(ACE). Three kinds of fish sauces were prepared from scrap(S), meat(M) and round(R) of sardine, respectively. ACE inhibitory activity of sardine sauce S and R decreased with the elapse of fermentation period, whereas that of sardine sauce M increased to 30 days and thereafter decreased. ACE inhibitory activity of sardine sauce M fermented with koji was higher than that without koji. And occurrence of $5\%$ TCA soluble peptide-nitrogen was similar to tendancy of the ACE inhibitory activity. The ACE inhibitory activity increased with an increment of amounts added and was stable at heat treatment in boiling water bath for 5hrs. $IC_{50}\%$ (Amounts of inhibitors need for $50\%$ inhibition) of the sardine sauce S, M and R fermented with(without) koji during 90 days was $125{\mu}g(140{\mu}g),\;200{\mu}g(100{\mu}g)$ and $125{\mu}g(135{\mu}g)$, respectively. From the profiles of fractionation of the sardine sauce R fermented without koji for 90 days, the molecular weight of most active fraction was about 1,400 and the amino acids of Glu, Ala, Leu and Lys were found in abundance.

• Journal of the Korean Magnetic Resonance Society
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• v.10 no.1
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• pp.115-125
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• 2006

Hippuryl-L-histidyl-L-leucine(HHL) is widely used as a substrate of angiotensin converting enzyme(ACE) cleaving the neurotransmitter angiotensin(I) to the octapeptide angiotensin(II). The structure of the substrate molecules should provide information regarding the geometric requirements of the ACE active site. For the purpose of determination of in vivo reaction, metallo(Cu, Zn)-HHL complexes were synthesized and the degree of complex formation were identified by MALDITOF, ESI mass spectrometric analysis. Tn addition, the pH-dependent species distribution curves were obtained by potentiometric titration. Nitrogen atoms of imidazole ring and oxygen atom of caboxylate groups in the peptide chain were observed to be participated in the metal complex formation. After purification of complexes further structural characterization were made by utilizing UV-Vis, electrochemical methods and NMR. Complete NMR signal assignments were carried out by using 2D-spectrum techniques COSY, TOCSY, NOESY, HETCOR. A complex that two imidazole and carboxylate groups are asymmetrically participating to coordination mode was predicted to the solution-state structure of $Cu(II)-HHL_2$ based on $^{13}C-NMR$ signal assignment and NOE information.

• Journal of Ginseng Research
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• v.14 no.2
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• pp.157-161
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• 1990

We have been isolating various physiologically active substances from non-saponin fraction of Korean Red Ginseng. These are adenosine, pyre-glutamic acid, dencichine and acidic polysaccharide. Adenosine and pyre-glutamic acid are known to inhibit epinephrine-induced lipolysis in fat cells and stimulate the insulin-mediated lipogenesis. In addition to these actions, adenosine was found to inhibit both norepinephrine- and histamine-induced aorta constriction, and pyre·glutamic acid inhibits angiotensin-converting enzyme. Dencichine stimulated histamine-induced aorta constriction. Finally, acidic polysaccharide was found to inhibit both lipolytic and anorexigenic actions of Toxohormone-L. Based on these experimental results, I presented a briefreview on these compounds isolated from non-saponin fraction of Korea Red Ginseng.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.721-725
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• 2001

Physiological activity in different parts of Dolsan leaf mustard (DLM) was investigated. To determine the physiological activity, DLM was crushed filtered centrifuged and then the supernatant was used as a sample. of 1%, 3% and 6%. By adding of improved root juice(20th day) with the concentration of 6% the cytotoxicity against HepG2 was the highest about 78.2%. And antioxidative effects in different parts of DLM was measured by using the DPPH method. Antioxidative effects was higher in all leaves than other parts. In particular antioxidative effects was the highest in leaves of traditional DLM at the 20th day of growth about 80.4%. In leaves of improved DLM at the 60th growth angiotensin-I converting enzyme inhibitory effect was the highest about 94.0%. Consequently there was not significant difference of physiological activity between improved and traditional DLM. However the cytotoxicity against HepG2 was the highest in roots of DLM. And the antioxidative and the ACE inhibitory effect in leaves of DLM were higher than those of other parts.

• Tuberculosis and Respiratory Diseases
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• v.39 no.4
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• pp.310-317
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• 1992

Background: Angiotensin converting enzyme is a glycoprotein peptidyldipeptide hydrolase which cleaves the c-terminal dipeptides of several oligopeptides. It is a menbrane-bound protein mainly synthesized by the endothelial cells. Since the lung has the largest capillary bed of any organ in the body, it is here that ACE acts on circulating substrates like angiotensin I and bradykinin. It is well known that ACE correlates with disease activity in sarcoidosis and also there are reports that changes in serum ACE activity are found in many acute and chronic lung diseases. So we planned this study to see if serum ACE activity can act as a prognostic factor in lung cancer. Methods: Forty-one newly diagnosed lung cancer patients were included in the study group. There were 19 patients with squamous cell lung cancer, 13 with adenocarcinoma, and 9 with small cell carcinoma. Patients were excluded from the study if they had high blood pressure, heart disease, liver disease, renal disease, or other lung disease. Serum ACE activity was analyzed according to cell type, staging, mode of treatment, and clinical response to treatment. Results: 1) There was no difference in serum ACE activity between lung cancer patients and the control group. Also no difference in serum ACE activity was found according to cancer cell type or staging. 2) In patients who underwent curative resection of lung cancer, serum ACE activity was decreased significantly after the operation. 3) In patients who were diagnosed as non-small cell lung cancer and were treated with 4 cycles of anti-cancer chemotherapy without clinical improvement, changes in serum ACE activity were not seen after the treatment. 4) In patients diagnosed as small cell lung cancer treated with 4 cycles of anti-cancer chemotherapy with clinical improvement, changes in serum ACE activity were also not observed. Conclusion: Serum ACE activity was decreased after lung resection but had no relation to cell type, staging, or clinical response to treatment in lung cancer patients. Therefore, serum ACE activity is not suitable in predicting clinical outcome of lung cancer patients.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.11
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• pp.1701-1708
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• 2014

Phenolic compounds, physiological properties, and digestive enzyme inhibitory effect of 70% ethanol extracts from Aster scaber with different extraction methods (stirrer extraction, SE; reflux extraction, RE; autoclave extraction, AE; low temperature high pressure extraction, LTPE; ultrasonification extraction, USE) were investigated. Total polyphenols and flavonoids contents in LTPE were significantly higher than those of other extracts. The amount of substances related to cynarin (1,3-O-dicaffeoylquinic acid) was highest in USE (34.34 mg/g), followed by LTPE (33.83 mg/g), RE (32.27 mg/g), AE (25.40 mg/g), and SE (18.17 mg/g). Chlorogenic acid (5-O-caffeoylquinic acid) and astragalin (kaempferol-3-O-glucopyranoside) were highest in AE and LTPE, respectively. Xanthine oxidase, angiotensin- I converting enzyme, 3-hydroxy-3-methylglutaryl coenzyme A reductase and acetylcholin esterase inhibitory activities of LTPE and USE at a concentration of 50 mg% (w/v) were somewhat higher than those of other extracts. The ${\alpha}$-amylase, ${\alpha}$-glucosidase, trypsin and lipase activities showed the same tendency as physiological properties (concentration of 500 mg%, w/v). Additionally, there was significantly higher or slightly lower inhibitory activity compared to the control group. These results suggest that extracts from Aster scaber have potential to act as functional materials, and LTPE and USE are superior for the enhancement of biological activity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.5
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• pp.426-433
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• 2009

Fish scales have potential in functional food preparation due to their antioxidant and antihypertensive properties. We investigated the angiotensin I converting enzyme (ACE) inhibitory activity of Tilapia mossambica scale extracts. Hydrolysates of tilapia scales were prepared by enzymatic extraction using five proteases (${\alpha}$-chymotrypsin, Alcalase, Kojizyme, Protamex and trypsin) after scales were treated with hot water for 3 hr. Scale enzymatic hydrolysates prepared using both hot water and enzyme treatments exhibited elevated hydrolysis (about 25%-55%) compared to only enzyme treatment (about 15%-45%). Enzymatic hydrolysates (1 mg/mL) prepared by both hot water and enzyme treatments also showed significantly increased ACE inhibitory activities from about 20%-75%. The pattern of ACE inhibitory activities was similar to the degree of hydrolysis. Alcalase and ${\alpha}$-chymotrypsin hydrolysates displayed the highest ACE inhibitory activities ($IC_{50}$ = 0.83 mg/mL and 0.68 mg/mL, respectively). In addition, the ACE inhibitory effects of $IC_{50}$-chymotrypsin hydrolysates increased with decreasing molecular weight (5 kDa>, 10 kDa> and 30 kDa>), with the 5 kDa> fraction displaying the highest ACE inhibitory activity (about 89.9% and $IC_{50}$ = 0.1 mg/mL). We suggest that the peptide compounds of enzymatic hydrolysates prepared from tilapia scale enhances ACE inhibitory activity and might be useful as an antihypertensive material.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.1
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• pp.45-53
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• 1997

In humans and many animal models with chronic progressive renal diseases, angiotensin-converting enzyme (ACE) inhibitor markedly attenuates the progression of nephropathy. Several studies have reported augmented gene expression and redistribution of renal renin in partial nephrectomized rats. Although precise mechanism(s) is not known, the renin-angiotensin system (RAS) may play an important role in the progression of renal diseases. Thus, this study was undertaken to examine the gene expression of renal renin, angiotensinogen, and $AT_1$ subtypes ($AT_{1A}$ and $AT_{1B}$) in rats with diabetic nephropathy, and the influences of lipopolysaccharide (LPS)-induced septicemia on the gene expression. Four weeks after streptozotocin (STZ) treatment (55 mg/kg, i.p.), rats were randomly divided into LPS-treated (1.6 mg/kg, i.p.) and control rats. At 6 hours after LPS treatment, the rats were killed and the kidney was removed from each rat. Northern blot and reverse transcription-polymerase chain reaction (RT-PCR)techniques were used to detect mRNA expression. STZ treatment markedly attenuated body weight gain and significantly increased blood glucose level. Renal renin content (RRC) was significantly decreased in the STZ-treated rats compared to that in control rats. The renal ACE activity between STZ-treated and control rats was not significantly different. Renal renin mRNA level was prominently increased, while angiotensinogen and $AT_{1A}$ mRNA levels were slightly decreased in STZ-treated rats compared to those in controls. $AT_1$B mRNA level did not differ in both groups. Acute LPS treatment did not show any significant changes of mRNA levels of intrarenal RAS components in both groups. These results suggest that intrarenal RAS components were differentially regulated in STZ-treated diabetic rats. Further studies are required to evaluate the relationship between intrarenal RAS and other vasomodulatory systems.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.2
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• pp.127-133
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• 2019

Seahorses have long been used as ornamental and medicinal products. The sea horse Hippocampus abdominalis has a beautiful color and unique shape and is also used for ornamental purposes and as a traditional medicine in China. This study examined the value of H. abdominalis as a health functional food or food additive. H. abdominalis was hydrolyzed using seven proteases: flavourzyme, neutrase, alcalase, trypsin, kojizyme, pepsin and protamex. The yields of all of the enzyme hydrolysates were higher than that of the aqueous extract. Of the enzymatic hydrolysates, seahorse Protamex hydrolysate (SHP) gave the highest yield and had excellent antioxidant and angiotensin-I converting enzyme inhibitory activities. It protected Vero cells against oxidative by 2,2-azobis-(2-amidinopropane) dihydrochloride (AAPH) and antihypertension in Spontaneously Hypertensive Rats. This study attempted to demonstrate H. abdominalis as a health functional food or food additive in the future.