• The Korean Journal of Physiology
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• 제20권1호
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• pp.89-102
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• 1986

It has long been suggested that the change of renin-angiotensin system is responsible for the increased arterial blood pressure in the experimental hypertension. But the exact nature of the cause and maintenance of early and late Phase of renal hypertension is still controversial. Increased renin-angiotensin system has been suggested. To clarify the altered renin-angiotensin system in the early phase of two kidney one clip Goldblatt hypertension(2K1C GH), experiments were carried out in the rats of 3,7, and 14 days of 2K1C GH rats, sham-operated, and control rats. Responses of the plasma renin activity to the intravenous infusion of L-isoproterenol were dose-dependent. Responses of the plasma renin activity to the intravenous L-isoproterenol in 2K1C GH rats were not different from sham-operated control rats. Hypotensive responses of the 2K1C GH rats were not different from sham-operated rats. Suppression by intravenous infusion of angiotensin II of plasma renin activity showed a dose-dependent manner. Suppression by angiotensin ll of plasma renin activity was attenuated or abolished in the early phase of 2K1C GH rats. Intravenous infusion of arginine vasopressin(AVP) showed a dose-dependent suppression of plasma renin activity, Attenuated responses by AVP of plasma renin activity were noticed in the early phase of 2K1C GH rats. These results suggest that the altered renin-angiotensin system in the early phase of the two kidney one clip Goldblatt hypertension may be caused by failure of the short loop negative feedback control mechanism.

• The Korean Journal of Physiology and Pharmacology
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• 제24권4호
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• pp.319-328
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• 2020

High fructose intake induces hyperglycemia and hypertension. However, the mechanism by which fructose induces metabolic syndrome is largely unknown. We hypothesized that high fructose intake induces activation of the renin-angiotensin system (RAS), resulting in hypertension and metabolic syndrome. We provided 11-week-old Sprague-Dawley rats with drinking water, with or without 20% fructose, for two weeks. We measured serum renin, angiotensin II (Ang II), and aldosterone (Aldo) using ELISA kits. The expression of RAS genes was determined by quantitative reverse transcription polymerase chain reaction. High fructose intake increased body weight and water retention, regardless of food intake or urine volume. After two weeks, fructose intake induced glucose intolerance and hypertension. High fructose intake increased serum renin, Ang II, triglyceride, and cholesterol levels, but not Aldo levels. High fructose intake increased the expression of angiotensinogen in the liver; angiotensin-converting enzyme in the lungs; and renin, angiotensin II type 1a receptor (AT1aR), and angiotensin II type 1b receptor (AT1bR) in the kidneys. However, expression of AT1aR and AT1bR in the adrenal glands did not increase in rats given fructose. Taken together, these results indicate that high fructose intake induces activation of RAS, resulting in hypertension and metabolic syndrome.

• The Korean Journal of Physiology and Pharmacology
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• 제3권3호
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• pp.315-320
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• 1999

Molecular regulation of the renin-angiotensin system (RAS) was investigated in deoxycorticosterone acetate (DOCA)-salt hypertension. The expression of renin, angiotensinogen and angiotensin II receptor genes in the kidney and liver was determined by Northern blot analysis in rats which were made DOCA-salt hypertensive over the period of 2 or 4 weeks. Along with the hypertension, renin mRNA was decreased in the remnant kidney. The expression of angiotensinogen gene was not significantly altered in the kidney, but was significantly decreased in the liver. The expression of angiotensin II receptor gene was increased in the kidney, while it remained unaltered in the liver. The duration of hypertension did not affect the altered gene expression. It is suggested that the components of RAS are transcriptionally regulated in DOCA-salt hypertension in a tissue-specific manner.

• The Korean Journal of Physiology
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• 제20권2호
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• pp.236-248
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• 1986

Alterations of renin-angiotensin system have been suggested as one of the mechanisms increasing arterial blood pressure in experimental and clinical hypertension. But the exact nature of high blood pressure in the early and late phase of renal hypertension is still controversial. To clarify the nature of renin release in both unclipped and clipped kidney of two kidney one clip Goldblatt lypertensive rat, experiments have been done in kidney slices, which were obtained from the rats of 3 and 7 days of operation. Basal rate of renin release was suppressed in unclipped kidney slices compared to clipped kidney Norepinephrine increased renin release from unclipped kidney slices, but not from clipped kidney slices. Suppressions by angiotensin Il and arginine vasopressin of renin release were attenuated in the clipped kidney slices compared to unclipped and sham-operated kidney slices. Increases by verapamil and trifluoperazine of renin release were attenuated in the clipped kidney slices compared to unclipped and sham-operated kidney slices. These results suggest that the negative feedback control mechanism of the renin-angiotensin system by angiotensin Il and arginine vasopressin is attenuated in the clipped kidney of two kidney one clip Goldblatt hypertensive rat, and that one of the altered mechanisms may be caused by certain regulatory changes of intracellular calcium and/or calcium-calmodulin complex in the juxtaglomerular cells.

• 대한핵의학회지
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• 제10권1호
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• pp.1-14
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• 1976

The etiologic role of renin-angiotensin system and sodium-volume status in the pathophysiology of various forms of hypertension was investigated. Plasma renin activity (PRA) was measured by radioimmunoassay, while sodium-volume status was evaluated by the determination of total exchangeable sodium(NaE) using isotope dilution method. The subjects consisted of 25 controls, 24 patients with essential hypertension, with chronic renal failure (13 with hypertension, 9 without hypertension) and with malignant hypertension. The results were as follows: 1. An inverse correlation between NaE and PRA was noted in control subjects (r=-0.598, p<0.001) and normal renin essential hypertension(r=-0.551, p<0.05) and the chronic renal failure with hypertension. (r=-0.790, p<0.001) 2. NaE increased markedly the in chronic renal failure with hypertension ($66.9{\pm}8.69mEq/kg$ of LBM, p<0.001) and the chronic renal failure without hypertension ($54.9{\pm}9.28mEq/kg$ of LBM, p<0.05), while mild increase was noted in malignant hypertension ($51.7{\pm}6.24mEq/kg$ of LBM, 0.05$50.1{\pm}7.24mEq$) as well as in its renin subgroups.(p>0.1) 3. Absolute value of PRA was not deviated significantly from control group ($2.53{\pm}1.416ng/ml/hr$) except in malignant hypertension ($6.09{\pm}2.042$, p<0.001). But PRA was inappropriately high in relation to prevailing NaE in the chronic renal failure with hypertension (eleven of thirteen patients) and malignant hypertension (ten of fourteen patients), while PRA variatiation was within physiologic range in the chronic renal failure without hypertension. 4. The NaE-PRA product was markedly increased in the chronic renal failure with hypertension ($514.4{\pm}42.10$, p<0.001) and in malignant hypertension ($442.7{\pm}55.03$, p<0.001), while moderately increased NaE-PRA product was noted in the chronic renal failure without hypertension ($402.6{\pm}59.67$, p<0.001). No significant difference in NaE-PRA product was noted in essential hypertension ($354.4{\pm}62.38$, p>0.1). It is suggested that renin-angiotensin system plays a predominant role in the pathogenesis of malignant hypertension and in hypertension of chronic renal failure, though sodium retention is also contributing factor. PRA variation in essential hypertension does not appear to be associated with any consistent change in Na-volume status, suggesting the existence of another mechanism in the genesis of hypertension and PRA variation.

• The Korean Journal of Physiology
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• 제19권2호
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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.

• The Korean Journal of Physiology and Pharmacology
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• 제5권3호
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• pp.253-258
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• 2001

The present study was aimed to examine whether the expression of renin is associated with that of cyclooxygenase-2 (COX-2) in the kidney. Male Sprague-Dawley rats were made two-kidney, one clip (2K1C) or deoxycorticosterone acetate (DOCA)-salt hypertensive, to stimulate or to inhibit the endogenous renin-angiotensin system, respectively. The expression of renin and COX-2 mRNA was determined in the cortex of the kidney by reverse transcription-polymerase chain reaction. 2K1C hypertensive rats showed an increased expression of renin as well as of COX-2 in the clipped kidney. The expression of renin was decreased in parallel with that of COX-2 in the contralateral non-clipped kidney. Removal of the renal arterial clip reversed the expression of both genes, along with the blood pressure, to the control level. On the other hand, DOCA-salt hypertension was associated with parallel decreases of renin and COX-2 expression. These results indicate that renin and COX-2 genes are coordinately expressed in the kidney.

• 한국환경성돌연변이발암원학회지
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• 제22권1호
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• pp.12-21
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• 2002

Genetic polymorphisms of the renin-angiotensin system (RAS) have been associated with hypertension in various ethnic groups, but no relation between these polymorphisms and hypertension has yet been systematically evaluated. To assess the relationship between allelic variation of RAS genes and hypertension, we performed the case-control studies using genetic markers in Korean normotensives and hypertensives. The allele and genotype frequencies of RAS genes in Korean population were not significantly different between normotensives and hypertensives. To investigate the distribution of allele frequencies among various populations, the data obtained in this study were compared to those in other ethnic groups studied previously. Except for T174M polymorphism of angiotensinogen (AGT) gene, allele frequencies of RAS genes were different among racial groups. The reason for these differences may be due to the difference in various genetic or environmental background or due to the effects by various sample size studied. In addition, it can be emphasized that carefully designed studies are required to minimize the ethnic heterogeneity of the case and control populations.

• Clinical and Experimental Pediatrics
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• 제62권4호
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• pp.144-147
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• 2019

The most common type of refractory hypertension found in children is secondary hypertension, which is a potentially curable disease. Reninoma, a renin-secreting juxtaglomerular cell tumor, is a rare cause of severe hypertension that is usually diagnosed in adolescents and young adults. Surgical resection of the tumor completely cures the hypertension of patients with reninoma. The typical clinical presentation of reninoma includes hypokalemia, metabolic alkalosis, and features secondary to the increased activation of the renin-angiotensin system without renal artery stenosis. We report a case of reninoma in a female adolescent with a typical clinical presentation, in which surgical removal of the tumor completely cured hypertension. We discuss here the clinical features, imaging studies, and immunohistochemical examination of the tumor used to establish the diagnosis of reninoma and for the management of the condition.

• 대한한의학방제학회지
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• 제24권3호
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• pp.175-193
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• 2016

Objective : Diuretics are effective on the patients with hypertension and heart failure, as well as edema by regulating the function of kidney, which is key organ to maintain the balance of the different electrolytes in the body. The present review article is designed to review the diuretic effect of Korean medicinal prescription base on the experimental studies.Method : For this purpose, every article related to ‘diuresis’ and 'Korean medicinal prescription' were analysed from articles which published at domestic and international journals.Results : 1. Representative Korean medicine prescriptions showed diuretic effect along with electrolyte excretion were Oryeong-san, Paeryung-tang, Hwangryungbokryung-tang and Daeganghwal-tang. 2. Some Korean medicinal prescription including Oryeong-san, Jueryeong-tang, Sipcho-tang distribute diuresis through the inhibition of renin-angiotensin-system. 3. Oryeong-san, Bojungchiseup-tang had a diuretic effect on the down-regulation of aquaporin water channel in the renal collecting duct.Conclusion : Korean medicinal transcriptions have a diuretic effect through several types of mechanism such as along with electrolytes excretion, inhibition of renin-angiotensin system, and down-regulation of water channels.