Role of Persistent Vascular Renin after Bilateral Nephrectomy in Goldblatt-Two Kidney Hypertension

1978 ◽  
Vol 55 (s4) ◽  
pp. 23s-26s ◽  
Author(s):  
H. Thurston ◽  
B. C. Hurst ◽  
R. F. Bing ◽  
J. D. Swales

1. Aortic homogenate contains renin-like activity which on incubation generates angiotensin I over a wide pH range. 2. Rat aortic renin measured at an incubation pH of 6·5 rose and fell in parallel to plasma renin with salt depletion and salt-loading respectively. Renin measured at an incubation pH of 5·3 showed little relationship with plasma renin. 3. Aortic renin (pH 6·5) was elevated in Goldblatt-two kidney hypertension and slowly fell for 24 h after bilateral nephrectomy whereas the fall in plasma renin was complete by the first hour. Aortic renin (pH 5·3) was also high, but did not fall after bilateral nephrectomy. 4. Aortic renin (pH 6·5) is probably derived from plasma renin whereas renin measured at pH 5·3 is probably a tissue renin. 5. The prolonged half-life of aortic renin (pH 6·5) explains the observation that the renin—angiotensin system appears to be active in maintaining blood pressure for several hours after bilateral nephrectomy whereas the decline in plasma renin is rapid and does not continue significantly beyond 1 h.

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 ◽  
...  

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.


1979 ◽  
Vol 236 (3) ◽  
pp. H409-H416 ◽  
Author(s):  
M. Shibota ◽  
A. Nagaoka ◽  
A. Shino ◽  
T. Fujita

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.


1982 ◽  
Vol 243 (1) ◽  
pp. E48-E51 ◽  
Author(s):  
H. Suzuki ◽  
M. Handa ◽  
K. Kondo ◽  
T. Saruta

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.


1994 ◽  
Vol 4 (12) ◽  
pp. 1987-1994 ◽  
Author(s):  
T Shinzato ◽  
M Miwa ◽  
S Nakai ◽  
H Morita ◽  
H Odani ◽  
...  

First, this investigation showed that plasma levels of inosine, hypoxanthine, and xanthine, which are metabolites of adenosine, rose sharply when blood pressure dropped suddenly along with symptoms during a hemodialysis session (sudden hypotension), but not when it decreased gradually with eventual symptoms (gradual hypotension). Because adenosine has an action to dilate vessels, this result indicates the possibility that the increased release of adenosine would be a cause of sudden hypotension. Second, it was found that the frequency of sudden hypotension decreases with the administration of caffeine, which is an adenosine-receptor antagonist, whereas the frequency of gradual hypotension did not change. This result supports the above-mentioned hypothesis that adenosine may well be a mediator of sudden hypotension, but not of gradual hypotension. Third, our investigation demonstrated no significant differences in plasma norepinephrine level, in plasma renin activity, or in mean blood pressure between the hemodialysis session in which caffeine was administered and the session in which a placebo was given. These findings suggest that the effect of caffeine administration to prevent sudden hypotension is not mediated by the stimulation of the sympathetic nervous system or activation of the renin-angiotensin system, but by the adenosine-receptor antagonism.


1968 ◽  
Vol 59 (3) ◽  
pp. 519-528 ◽  
Author(s):  
J. D. Elema ◽  
M. J. Hardonk ◽  
Joh. Koudstaal ◽  
A. Arends

ABSTRACT In order to evaluate a possible role of the renin-angiotensin system in enzyme histochemical changes of the rat adrenal cortex seen after acute hyponatraemia, the effect of a preceding total nephrectomy was investigated. By this procedure it was found that the alterations were largely inhibited. The results therefore favour a role of the renin-angiotensin system in these changes. Moreover it was found that bilateral nephrectomy alone also induced an enhanced zona glomerulosa activity which may be due to a direct effect of changes in potassium homoeostasis.


1976 ◽  
Vol 51 (s3) ◽  
pp. 125s-127s
Author(s):  
H. Thurston ◽  
J. D. Swales

1. Infusion of angiotensin II antagonist failed to restore the blood pressure of short-term Goldblatt 2-kidney hypertensive rats to normal levels before and after sodium restriction. 2. The blood pressure of both normal and sodium-restricted Goldblatt 2-hypertensive rats remained elevated 6 h after bilateral nephrectomy. 3. The residual hypertension found during antagonist infusion and after bilateral nephrectomy is not maintained by the renin—angiotensin system or sodium retention.


1980 ◽  
Vol 239 (3) ◽  
pp. F271-F280 ◽  
Author(s):  
J. E. Hall ◽  
A. C. Guyton ◽  
M. J. Smith ◽  
T. G. Coleman

The present study was designed to quantitate the role of the renin-angiotensin system (RAS) in determining the chronic relationships between arterial pressure (AP), renal hemodynamics, and Na excretion. In six control dogs, Na balance was achieved during chronic step increases in Na intake from 5 to 500 meq/day with small increases in AP (<7 mmHg), moderate increases in GFR (19%), and decreases in filtration fraction (FF) and plasma renin activity. Similar increases in Na intake in six dogs with angiotensin II (AII) fixed, due to constant intravenous infusion of 5 ng . kg-1 . min-1 AII, caused large increases in AP (42%), GFR (31%) FF, and calculated renal Na reabsorption (TNa) above control. In six dogs with AII formation blocked with SQ 14,225, Na balance at intakes of 5-80 meq/day occurred at reduced AP, GFR, FF, and TNa, although plasma aldosterone concentration (PAC) was not substantially different from that in control dogs. At Na intakes above 240 meq/day, AP was not altered by SQ 14,225. These data indicate that during chronic changes in Na intake the RAS plays a major role, independent of changes in PAC, in allowing Na balance without large changes in GFR or AP. The mechanism whereby AII conserves Na chronically is through increased TNa, since steady-state TNa was increased by AII and decreased by SQ 14,225.


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