• The Korean Journal of Physiology and Pharmacology
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• 제1권4호
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• pp.413-423
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• 1997

The importance of the kidney in the development of hypertension was first demonstrated by Goldblatt and his colleagues more than fifty years ago. Many hormones and other regulatory factors have been proposed to play a major role in the development of hypertension. Among these factors angiotensia II (ANG II) is closely involved in renal hypertension development since it directly regulates $Na^+$ reabsorption in the renal proximal tubule. Thus the aim of the present study was to examine signaling pathways of low dose of ANC II on the $Na^+$ uptake of primary cultured rabbit renal proximal tubule cells (PTCs) in hormonally defined seum-free medium. The results were as follows: 1) $10^{-11}$ M ANG II has a significant stimulatory effect on growth as compared with control. Alkaline phosphatase exhibited significantly increased activity. However, leucine aminopeptidase and ${\gamma}-glutamyl$ transpeptidase activity were not significant as compared with control. In contrast to $10^{-11}$ M ANG II stimulated $Na^+$ uptake $(108.03{\pm}2.16% of that of control)$, $10^{-9}$ M ANG II inhibited ($92.42{\mu}2.23%$ of that of control). The stimulatory effect of ANG II on $Na^+$ uptake was amiloride-sensitive and inhibited by losartan (ANG II receptor subtype 1 antagonist) and not by PD123319 (ANG II receptor subtype 2 antagonist). 2) Pertussis toxin (PTX) alone inhibited $Na^+$ uptake by $85.52{\pm}3.52%$ of that of control. In addition, PTX pretreatment prevented the AMG II-induced stimulation of $Na^+$ uptake. 8-Bromoadenosine 3',5'-cyclic monophosphate (8-Br-cAMP), forskolin, and isobutylmethylxanthine (IBMX) alone inhibited $Na^+$ uptake by $88.79{\pm}2.56,\;80.63{\pm}4.38,\;and\;84.47{\pm}4.74%$ of that of control, respectively, and prevented the ANG II-induced stimulation of $Na^+$ uptake. However, $10^{-11}$ M ANG II did not stimulate cAMP production. 3) The addition of 12-O-te-tradecanoylphorbol-13-acetate (TPA, 0.01 ng/ml) to the PTCs produced significant increase in $Na^+$ uptake ($114.43{\pm}4.05%$ of that of control). When ANG II and TPA were added together to the PTCs, there was no additive effect on $Na^+$ uptake. Staurosporine alone had no effect on $Na^+$ uptake, but led to a complete inhibition of ANG II- or TPA-induced stimulation of Na'uptake. ANG II treatment resulted in a $111.83{\mu}4.51%$ increase in total protein kinase C (PKC) activity. In conclusion, the PTX-sensitive PKC pathway is the main signaling cascade involved in the stimulatory effects of ANG II on $Na^+$ uptake in the PTCs.

• 한국수산과학회지
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• 제26권4호
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• pp.321-329
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• 1993

수산자원의 기능특성 해명을 위한 연구의 일환으로 전통수산발효식품으로 널리 이용되고 있는 멸치젓갈에 함유되어 있는 angiotensin-I 전환효소저해물질을 추출하여 gel 여과에 의하여 분리된 획분들의 작용 및 특성에 대해서 살펴보았다. 그 결과를 요약하면 다음과 같다. 1. ACE 저해물질의 추출 조건을 검토하기 위하여 가장 높은 ACE 저해효과를 나타내는 숙성 60일차의 멸치젓갈을 ethanol 및 acetone의 농도를 각각 10, 25, 50 및 $80\%$로 하여 추출하였을 때 ethanol 농도가 $50\%$인 획분이 가장 우수한 저해효과를 나타내었다. 2. 멸치젓갈 숙성중 시료액의 $50\%$ ethanol 가용성 peptide-nitrogen 함량 및 ACE 저해효과는 아미노 질소 함량이 최고치에 달하는 숙성 60일차에 최대값을 나타내다가 그 후 다소 감소하는 경향을 나타내었다. 3. Gel 여과에 의한 멸치젓갈의 획분별 ACE 저해효과를 검토한 결과, 획분 C 및 D가 가장 높은 ACE 저해작용을 나타내어 이들을 rechromatography하여 분리한 단일 획분인 C'와 D'획분의 $IC_{50}$은 각각 97, $65{\mu}g$로 나타났다. 4. 분리한 단일 획분인 C'와 D'획분의 아미노산 조성은 다소 차이가 있었으며, C'획분은 threonine, glutamic acid 및 lysine의 함량이 많은 것으로 나타났으며, D'획분은 serine과 proline의 함량이 많은 것으로 나타났다.

• The Korean Journal of Physiology
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• 제27권1호
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• pp.57-66
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• 1993

Effects of a voltage dependent calcium channel antagonist, nifedipine, on the responses of blood pressure, and secretion of atrial natriuretic peptide (ANP) and aldosterone to angiotensin II (Ang II) were compared in male Wistar and spontaneously hypertensive rats (SHR). A low, control or high sodium diet (2, 10 or 25 mmol Na/100 g diet) was fed for 6 weeks from the age of 6 weeks. On the morning of the experiment catheters were inserted under ether anesthesia in the femoral artery for pressure recording and blood sampling, and in the femoral vein for drug infusion. Ang II was infused at a rate of 250 ng/kg/min for 20 min. Nifedipine mixed with Ang II was infused at a rate of $16{\mu}g/kg/min$ for 20 min. Arterial blood samples were collected before and after infusion of Ang II with or without nifedipine. The control plasma level of aldosterone was inversely related to the amount of salt intake, whereas the plasma ANP level was not different between the salt groups. SHR showed a higher basal plasma ANP but a lower aldosterone concentration than Wistar rats. Infusion of Ang II produced a significant increase in blood pressure and plasma levels of aldosterone and ANP: The % increase was not significantly different either between the salt groups or between SHR and Wistar rats. SHR showed a greater pressor response to Ang II but a remarkably smaller decrease in heart rate after Ang II infusion than Wistar rats, With increasing sodium intake, the effect of Ang II on aldosterone secretion was decreased, whereas that on ANP secretion or blood pressure was not changed. Nifedipine decreased the responses of blood pressure and heart rate to Ang II in all groups. Nifedipine caused almost a complete inhibition of Ang II induced ANP secretion, but only a partial inhibition of Ang II induced aldosterone secretion or vasoconstriction. These results indicate that calcium dependent processes were involved in Ang II induced vasoconstriction, and secretions of aldosterone and ANP. However, the calcium dependent process far ANP secretion was considerably different from that for aldosterone secretion or vasoconstriction evoked by ang II. The ang II induced increase in ANP secretion appeared to be caused primarily by activating voltage-dependent calcium channels, whereas Ang II induced aldosterone secretion and vasoconstriction was not.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2004년도 춘계학술발표대회
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• pp.252-252
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• 2004

1. The concentrations of Ang. Ⅱ were 7.2±0.91 × 10³, 3.8±0.34 × 10³, 3.5±0.30 × 10³, 2.8±0.22 × 10³ pg/㎖ in bovine follicular fluids from 1∼3 ㎜, 3∼5 ㎜, 5∼7 ㎜ and 8∼10 ㎜ follicles, respectively. However, the concentrations of Ang. Ⅱ decreased in follicular fluids from large follicles. (omitted)

• 대한임상약리학회:학술대회논문집
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• 대한임상약리학회 2001년도 춘계 심포지움
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• pp.9-10
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• 2001

• Clinical and Experimental Pediatrics
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• 제64권3호
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• pp.136-138
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• 2021

• 대한약학회:학술대회논문집
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• 대한약학회 2000년도 춘계총회 및 학술대회
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• pp.139.1-139.1
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• 2000

• 대한약학회:학술대회논문집
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• 대한약학회 2000년도 NEW STRATEGY FOR DRUG DEVELOPMENT IN POST-GENOMIC ERA(대한약학회)
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• pp.200.2-201
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• 2000

• Korean Circulation Journal
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• 제54권6호
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• pp.361-362
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• 2024

• The Korean Journal of Physiology
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• 제8권1호
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• pp.7-14
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• 1974

This study was carried out to investigate the acute changes in R-A-A system following lasix administration, and to evaluate the materials in plasma R-A-A system and electrolytic excretion every 30 minutes for 2 hours after lasix administration with normal high sodium Korean food, moderate sodium restriction, and severe sodium restriction, and it was concluded as followed; 1. Plasma renin activity, angiotensin II concentration, and aldosterone concentration elevated in course of time after lasix administration with high sodium Korean food, but the R-A-A system takes insignificant part because of the increasing rate was so slight. 2. Although the increasing rate of plasma renin activity reached lower levels, angiotensin II and aldosterone concentration were significantly increased after lasix administration with moderate sodium restriction. 3. It was observed that higher rise in aldosterone concentration following lasix administration during severe sodium restriction than when moderate sodium restriction. 4. Urinary sodium and potassium excretion during two hours after lasix administration showed decrease as little as the amount of sodium intake, but K/Na excretion ratio showed increase with small amount of sodium intake because of the decreasing rate of potassium was low value. 5. Sodium excretion after lasix administration reached more than 1.5 times of sodium intake, even though R-A-A reaction showed significantly. 6. As our results showed, R-A-A reaction following acute diuresis was insignificant with high sodium Intake, the increasing ratio of aldosterone concentration showed high rise compare with of plasma renin activity as little as the amount of sodium intake, and the participated rate in sodium reabsorption of R-A-A system was increased.