Role of renin-angiotensin system in glucocorticoid hypertension in rats

1982 ◽  
Vol 243 (1) ◽  
pp. E48-E51 ◽  
Author(s):  
H. Suzuki ◽  
M. Handa ◽  
K. Kondo ◽  
T. Saruta
Keyword(s):  
Blood Pressure ◽  
Intravenous Injection ◽  
Enzyme Inhibitor ◽  
Renin Angiotensin System ◽  
Plasma Renin ◽  
Dependent Manner ◽  
Concurrent Administration ◽  
Angiotensin System ◽  
Renin Angiotensin

The role of the renin-angiotensin system in the regulation of the blood pressure of dexamethasone-treated rats (Dex) was evaluated using saralasin, an angiotensin II antagonist, and SQ 14225 (SQ) (d-3-mercapto-2-methylpropranoyl-1-proline), an angiotensin-converting enzyme inhibitor. During a 7-day period blood pressure rose 65 +/- 10 mmHg (P less than 0.001) in Dex with no significant changes in plasma renin activity. Concurrent administration of dexamethasone and SQ attenuated the elevation of blood pressure (P less than 0.05). In the conscious, freely moving state, intravenous injection of SQ (10, 30, 100 micrograms/kg) reduced blood pressure of DEX in a dose-dependent manner (P less than 0.05). Also, intravenous injection of saralasin (10 micrograms.kg-1 . min-1) reduced blood pressure significantly (P less than 0.01). Bilateral nephrectomy abolished the effects of saralasin and SQ on blood pressure in Dex. These results indicate that the elevation of blood pressure in DEX depends partially on the renin-angiotensin system.

EVIDENCE OF A FUNCTIONAL RENIN-ANGIOTENSIN SYSTEM IN THE CHANNEL CATFISH (ICTALURUS PUNCTATUS)

2018 ◽  
Vol 70 (1) ◽  
Author(s):  
Justin C. Hunt ◽  
Kenneth A. Davis ◽  
Max G. Sanderford
Keyword(s):  
Blood Pressure ◽  
Ictalurus Punctatus ◽  
Channel Catfish ◽  
Enzyme Inhibitor ◽  
Renin Angiotensin System ◽  
Suitable Model ◽  
Dependent Manner ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Volume Balance

Abstract Salination of freshwater (FW) bodies has the potential to affect homeostatic regulation of osmotic and volume balance in FW organisms. The renin-angiotensin system (RAS) plays an important role in volume balance by maintaining blood pressure in marine and seawater acclimated euryhaline fish, but little is known about the RAS in FW adapted fish. The purpose of the present study was to first determine if the FW channel catfish (Ictalurus punctatus), demonstrates evidence of a functional RAS. Channel catfish (n = 6) were implanted with a catheter in the dorsal aorta to measure dorsal aortic pressure (PDA) and infuse drugs. Infusion of [Asn1,Val5,Asn9]-angiotensin I (ANGI) at 100, 400, and 1000 ng/kg significantly increased PDA in a dose dependent manner (P < 0.05). Pretreatment with 2 mg/kg of the angiotensin converting enzyme inhibitor, Captopril (CAP), essentially eliminated the pressor response to the highest dose of ANGI (P < 0.05). Finally, infusion of 400 ng/kg [Asn1,Val5]-angiotensin II (ANGII) significantly increased PDA from baseline (P < 0.05). The results suggest that channel catfish appear to have an operational RAS and may serve as a suitable model in which to study the role of ANGII in blood pressure regulation in FW adapted fish.

Response of Chronic Renovascular Hypertension to Surgical Correction or Prolonged Blockade of the Renin–Angiotensin System by Two Inhibitors in the Rat

1980 ◽  
Vol 58 (1) ◽  
pp. 15-20 ◽  
Author(s):  
H. Thurston ◽  
R. F. Bing ◽  
E. S. Marks ◽  
J. D. Swales
Keyword(s):  
Blood Pressure ◽  
Enzyme Inhibitor ◽  
Blood Pressure Response ◽  
Renin Angiotensin System ◽  
Plasma Renin ◽  
Chronic Hypertension ◽  
Converting Enzyme ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Converting Enzyme Inhibitor

1. Removal of the renal artery constriction but not of the clipped kidney restored the blood pressure to normal levels in Goldblatt two-kidney rats with hypertension of more than 4 months' duration. 2. Despite the differences in blood pressure response, both surgical procedures lowered plasma renin concentration to normal or below normal values. 3. Administration of the oral converting enzyme inhibitor SQ 14 225 produced a marked fall in blood pressure in Goldblatt kidney rats with chronic hypertension. However, a prolonged infusion of the angiotensin II antagonist saralasin was quite ineffective. The difference in response to the two inhibitors may have been due to bradykinin potentiation by the converting enzyme inhibitor. 4. Although plasma renin is often elevated in Goldblatt two-kidney rats with hypertension of more than 4 months' duration, the renin-angiotensin system plays no role in the maintenance of blood pressure at this stage.

The Renin Angiotensin System and Bipolar Disorder: A Systematic Review

2020 ◽  
Vol 27 (6) ◽  
pp. 520-528 ◽  
Author(s):  
Izabela Guimarães Barbosa ◽  
Giulia Campos Ferreira ◽  
Diomildo Ferreira Andrade Júnior ◽  
Cássio Rocha Januário ◽  
André Rolim Belisário ◽  
...  
Keyword(s):  
Systematic Review ◽  
Bipolar Disorder ◽  
Cardiovascular Diseases ◽  
Renin Angiotensin System ◽  
Plasma Renin ◽  
Angiotensin Receptors ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Search Terms

Bipolar Disorder (BD) is a chronic a multifactorial psychiatric illness that affects mood, cognition, and functioning. BD is associated with several psychiatric conditions as well clinical comorbidities, particularly cardiovascular diseases. The neurobiology of BD is complex and multifactorial and several systems have been implicated. Considering that the Renin Angiotensin System (RAS) plays an important role in cardiovascular diseases and that recently evidence has suggested its role in psychiatric disorders, the aim of the present study is to summarize and to discuss recent findings related to the modulation of RAS components in BD. A systematic search of the literature using the electronic databases MEDLINE and LILACS was conducted through March 2019. The search terms were: “Bipolar Disorder”; “Renin Angiotensin System”; “Angiotensin 2”; “Angiotensin receptors”; “Angiotensin 1-7”; “ACE”; “ACE2”; “Mas Receptor”. We included original studies assessing RAS in BD patients. Two hundred twenty-two citations were initially retrieved. Eleven studies were included in our systematic review. In the majority of studies (6 of 8), the ACE insertion/deletion (I/D) polymorphism did not differ between BD patients and controls. BD patients presented higher plasma renin activity in comparison with controls. The studies evaluating the RAS molecules in BD are very scarce and heterogeneous. The literature suggests a potential role of RAS in BD. Further studies are necessary to investigate this relationship.

Anti-Hypertensive Effect of Water Extract of Danshen on Renovascular Hypertension Through Inhibition of the Renin Angiotensin System

2002 ◽  
Vol 30 (01) ◽  
pp. 87-93 ◽  
Author(s):  
Dae Gill Kang ◽  
Yong Gab Yun ◽  
Jang Hyun Ryoo ◽  
Ho Sub Lee
Keyword(s):  
Plasma Concentration ◽  
Water Extract ◽  
Renin Angiotensin System ◽  
Plasma Renin ◽  
Dependent Manner ◽  
Converting Enzyme ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Ace Activity ◽  
Dose Dependent

A study was designed to elucidate the mechanism of anti-hypertensive effects of Danshen in the two-kidney, one clip (2K1C) Goldblatt renovascular hypertensive model, which is the renin-angiotensin system (RAS)-dependent hypertensive model. We investigated the effects of water extracts of Danshen on the angiotensin converting enzyme (ACE) activities, systolic blood pressure (SBP), and hormone levels in the plasma of 2K1C rats. ACE activity was inhibited by the addition of Danshen extract in a dose-dependent manner. SBP was decreased significantly after administration of Danshen extract in 2K1C, whereas plasma renin activity (PRA) was not changed. The plasma concentration of aldosterone (PAC) was decreased significantly in 2K1C group administered with Danshen extract, whereas the plasma concentration of ANP was increased by administration of Danshen extract for three weeks. These results suggest that Danshen has an anti-hypertensive effect through the inhibition of ACE, an essential regulatory enzyme of RAS.

Renin-angiotensin system in stroke-prone spontaneously hypertensive rats

1979 ◽  
Vol 236 (3) ◽  
pp. H409-H416 ◽  
Author(s):  
M. Shibota ◽  
A. Nagaoka ◽  
A. Shino ◽  
T. Fujita
Keyword(s):  
Blood Pressure ◽  
Spontaneously Hypertensive Rats ◽  
Renin Angiotensin System ◽  
Plasma Renin ◽  
Malignant Hypertension ◽  
Hypertensive Rats ◽  
Salt Loading ◽  
Angiotensin System ◽  
Spontaneously Hypertensive ◽  
Renin Angiotensin

The development of malignant hypertension was studied in stroke-prone spontaneously hypertensive rats (SHR) kept on 1% NaCl as drinking water. Along with salt-loading, blood pressure gradually increased and reached a severe hypertensive level (greater than 230 mmHg), which was followed by increases in urinary protein (greater than 100 (mg/250 g body wt)/day) and plasma renin concentration (PRC, from 18.9 +/- 0.1 to 51.2 +/- 19.4 (ng/ml)/h, mean +/- SD). At this stage, renal small arteries and arterioles showed severe sclerosis and fibrinoid necrosis. Stroke was observed within a week after the onset of these renal abnormalities. The dose of exogenous angiotensin II (AII) producing 30 mmHg rise in blood pressure increased with the elevation of PRC, from 22 +/- 12 to 75 +/- 36 ng/kg, which was comparable to that in rats on water. The fall of blood pressure due to an AII inhibitor, [1-sarcosine, 8-alanine]AII (10(microgram/kg)/min for 40 min) became more prominent with the increase in PRC in salt-loaded rats, but was not detected in rats on water. These findings suggest that the activation of renin-angiotensin system participates in malignant hypertension of salt-loaded stroke-prone SHR rats that show stroke signs, proteinuria, hyperreninemia, and renovascular changes.

What Stimulates the Renin—Angiotensin System in Rats with two-Kidney Renal Hypertension?

1983 ◽  
Vol 64 (5) ◽  
pp. 463-470
Author(s):  
Y. Takata ◽  
A. E. Doyle ◽  
M. Veroni ◽  
S. G. Duffy
Keyword(s):  
Blood Pressure ◽  
Plasma Renin Activity ◽  
Renin Angiotensin System ◽  
Plasma Renin ◽  
Renin Activity ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Contralateral Kidney ◽  
The One ◽  
Renin Content

1. Blood pressure, the hypotensive effect of captopril, plasma renin activity, renal renin content and kidney weight were measured in the two-kidney—one-clip model, the one-kidney—one-clip model and the two-kidney—one-clip model with the ureter of the contralateral kidney ligated in rats. The ureteric ligation was performed to abolish urinary excretion from the contralateral kidney in the two-kidney—one-clip model. 2. The development of hypertension after renal artery constriction was earlier and greater in the one-kidney—one-clip model and the two-kidney—one-clip model with ureter of the contralateral kidney ligated than in the two-kidney—one-clip model. A single oral dose of captopril produced a greater fall in blood pressure in both the two-kidney models than in the one-kidney—one-clip group. 3. Plasma renin activity and renal renin content of the clipped kidney were higher in the two-kidney model rats, whether or not the ureter had been ligated, than in the one-kidney—one-clip model animals, although more than half the rats from the two-kidney model had normal values. There was a significant correlation between plasma renin activity and the response to captopril in all groups, whereas in none of the three groups was the correlation between plasma renin activity and blood pressure significant. 4. The clipped kidney had a higher renin content than did the contralateral kidney, and the weight of the ischaemic kidney was decreased compared with the contralateral kidney whether it was untouched or had its ureter ligated. The weight of the clipped kidney was in the order one-kidney—one-clip model > two-kidney—one-clip model with ureter of the contralateral kidney ligated > two-kidney—one-clip model. 5. It was concluded that the renin-angiotensin system was stimulated to the similar degree in some animals for the two-kidney—one-clip models, whether or not the ureter of the contralateral kidney had been ligated, compared with the one-kidney—one-clip animals. This finding suggests that the contralateral kidney can stimulate renin secretion and synthesis in the clipped kidney independently of Na+ excretion.

scholarly journals Rosiglitazone, a Ligand to PPARγ, Improves Blood Pressure and Vascular Function through Renin-Angiotensin System Regulation

PPAR Research ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
María Sánchez-Aguilar ◽  
Luz Ibarra-Lara ◽  
Leonardo Del Valle-Mondragón ◽  
María Esther Rubio-Ruiz ◽  
Alicia G. Aguilar-Navarro ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Angiotensin Ii ◽  
In Silico ◽  
Vascular Function ◽  
Renin Angiotensin System ◽  
Dependent Manner ◽  
Insulin Sensitizer ◽  
Angiotensin System ◽  
Renin Angiotensin

Rosiglitazone (RGZ), a peroxisome proliferator-activated receptor gamma (PPARγ) ligand, has been reported to act as insulin sensitizer and exert cardiovascular actions. In this work, we hypothesized that RGZ exerts a PPARγ–dependent regulation of blood pressure through modulation of angiotensin-converting enzyme (ACE)-type 2 (ACE2)/angiotensin-(1-7)/angiotensin II type-2 receptor (AT2R) axis in an experimental model of high blood pressure. We carried on experiments in normotensive (Sham) and aortic coarctation (AoCo)-induced hypertensive male Wistar rats. Both sham and AoCo rats were treated 7 days with vehicle (V), RGZ (5 mg/kg/day), or RGZ+BADGE (120 mg/kg/day) post-coarctation. We measured blood pressure and vascular reactivity on aortic rings, as well as the expression of renin-angiotensin system (RAS) proteins. We found that RGZ treatment in AoCo group decreases blood pressure values and improves vascular response to acetylcholine, both parameters dependent on PPARγ-stimulation. RGZ lowered serum angiotensin II (AngII) but increased Ang-(1-7) levels. It also decreased 8-hydroxy-2′-deoxyguanosine (8-OH-2dG), malondialdehyde (MDA), and improved the antioxidant capacity. Regarding protein expression of RAS, RGZ decreases ACE and angiotensin II type 1 receptor (AT1R) and improved ACE2, AT2R, and Mas receptor in AoCo rats. Additionally, an in silico analysis revealed that 5′UTR regions of RAS and PPARγ share motifs with a transcriptional regulatory role. We conclude that RGZ lowers blood pressure values by increasing the expression of RAS axis proteins ACE2 and AT2R, decreasing the levels of AngII and increasing levels of Ang-(1-7) in a PPARγ-dependent manner. The in silico analysis is a valuable tool to predict the interaction between PPARγ and RAS.

Role of adrenal renin-angiotensin system in the control of aldosterone secretion in sodium-restricted rats

2000 ◽  
Vol 278 (6) ◽  
pp. E1027-E1030 ◽  
Author(s):  
Giuseppina Mazzocchi ◽  
Ludwik K. Malendowicz ◽  
Anna Markowska ◽  
Giovanna Albertin ◽  
Gastone G. Nussdorfer
Keyword(s):  
Enzyme Inhibitor ◽  
Renin Angiotensin System ◽  
Zona Glomerulosa ◽  
Normal Diet ◽  
Angiotensin Ii Receptor ◽  
Aldosterone Secretion ◽  
Angiotensin System ◽  
Renin Angiotensin

This study examined the effect of the pharmacological manipulation of adrenal renin-angiotensin system (RAS) on aldosterone secretion from in situ perfused adrenals of rats kept on a normal diet and sodium restricted for 14 days. Neither the angiotensin-converting enzyme inhibitor captopril nor the nonselective angiotensin II receptor antagonist saralasin and the AT1 receptor-selective antagonist losartan affected basal aldosterone output in normally fed rats. In contrast, they concentration dependently decreased aldosterone secretion in sodium-restricted animals, with maximal effective concentration ranging from 10− 7 to 10− 6 M. Captopril (10− 6 M), saralasin (10− 6 M), and losartan (10− 7 M) counteracted aldosterone response to 10 mM K+ in sodium-restricted rats but not in normally fed animals. Collectively, these findings provide evidence that adrenal RAS plays a role in the regulation of aldosterone secretion, but only under conditions of prolonged stimulation of zona glomerulosa probably leading to overexpression of adrenal RAS.

Is angiotensin essential in drinking induced by water deprivation and caval ligation?

1981 ◽  
Vol 240 (1) ◽  
pp. R75-R80 ◽  
Author(s):  
M. C. Lee ◽  
T. N. Thrasher ◽  
D. J. Ramsay
Keyword(s):  
Blood Pressure ◽  
Angiotensin Ii ◽  
Water Intake ◽  
Water Deprivation ◽  
Essential Role ◽  
Vena Cava ◽  
Renin Angiotensin System ◽  
Angiotensin System ◽  
Renin Angiotensin

The role of the renin-angiotensin system in drinking induced by water deprivation and caval ligation was assessed by infusion of saralasin into the lateral ventricles of rats. This technique was first validated by demonstrating its capability to specifically antagonize drinking to both systemic and central angiotensin II. However, neither the latency to drink nor the amount of water consumed following 24- or 30-h water deprivation was affected by saralasin. Furthermore, saralasin had no significant effect on the recovery of blood pressure or on the water intake following ligation of the abdominal vena cava. These observations suggest that the renin-angiotensin system alone does not play an essential role in the control of drinking following water deprivation or caval ligation in rats.

Sign in / Sign up

Export Citation Format

Share Document