De-stiffening Strategy, Sodium Balance, and Blockade of the Renin–Angiotensin System

2014 ◽  
pp. 519-529
Author(s):  
Athanase D. Protogerou ◽  
Michel E. Safar ◽  
Gerard E. Plante ◽  
Jacques Blacher
Keyword(s):  
Renin Angiotensin System ◽  
Sodium Balance ◽  
Angiotensin System ◽  
Renin Angiotensin

RENIN, CORTISOL AND PLASMA VOLUME IN MARINE TELEOST FISHES ADAPTED TO DILUTE MEDIA

1976 ◽  
Vol 70 (1) ◽  
pp. 47-59 ◽  
Author(s):  
HIROKO NISHIMURA ◽  
W. H. SAWYER ◽  
R. F. NIGRELLI
Keyword(s):  
Fresh Water ◽  
Plasma Volume ◽  
Renin Angiotensin System ◽  
Plasma Renin ◽  
Sodium Balance ◽  
Plasma Sodium ◽  
Teleost Fishes ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
American Eels

SUMMARY The renin–angiotensin system has been found in teleost fishes from both marine and freshwater environments. In an attempt to define whether activity of the renin–angiotensin system is related to sodium balance in fishes, we transferred two euryhaline teleosts from seawater to hypo-osmotic media. Plasma renin activity decreased in American eels, Anguilla rostrata, after they were transferred from seawater to fresh water, and it did not change in the aglomerular toadfish, Opsanus tau, after transfer from 50% seawater to 5% seawater. Plasma sodium concentrations decreased significantly in toadfish in 5% seawater and in one group of eels in fresh water. Plasma levels of cortisol, a major mineralocorticoid in teleosts, and plasma volume, measured in eels, remained relatively constant. There are no clear correlations between plasma renin levels and those of plasma sodium or plasma cortisol. These results provide no evidence that the need of these fishes to conserve sodium when in hypo-osmotic media stimulates the renin–angiotensin system.

Role of the renin-angiotensin system in potassium control

1980 ◽  
Vol 238 (5) ◽  
pp. R359-R363
Author(s):  
D. B. Young ◽  
R. E. McCaa
Keyword(s):  
Potassium Concentration ◽  
Renin Angiotensin System ◽  
Plasma Potassium ◽  
Sodium Balance ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Low Sodium ◽  
Group I ◽  
Urinary Potassium ◽  
Group Ii

To determine the importance of the renin-angiotensin system in control of plasma potassium concentration and excretion, potassium control was studied in two groups of dogs in response to a 20-fold increase in sodium intake (from 10 to 200 meq/day). Group I was intact whereas group II lacked feedback control of the renin-angiotensin system, which was eliminated by continuous infusion of 10 ng . kg-1 . min-1 angiotensin II. This rate of infusion reduced endogenous plasma renin activity (PRA) to undetectable levels throughout the study. The sodium forcing did not result in measurable changes in plasma potassium concentration or excretion in group I, in which PRA fell to 40% and plasma aldosterone concentration (PAC) to 60% of the low sodium levels. In group II the same sodium forcing produced a 12% decrease in plasma potassium concentration and a 79% increase in urinary potassium excretion. PAC also fell to 60% of the low sodium level in group II. The results demonstrate the importance of the renin-angiotensin system as a link between the nephron and the zona glomerulosa that is essential in controlling plasma potassium concentration and excretion during changes in sodium balance.

Atrial natriuretic peptides in essential hypertension: basal plasma levels and relationship to sodium balance

1991 ◽  
Vol 69 (10) ◽  
pp. 1592-1600 ◽  
Author(s):  
G. A. Sagnella ◽  
N. D. Markandu ◽  
M. G. Buckley ◽  
M. A. Miller ◽  
D. R. J. Singer ◽  
...  
Keyword(s):  
Essential Hypertension ◽  
Natriuretic Peptides ◽  
Renin Angiotensin System ◽  
Dietary Sodium ◽  
Sodium Balance ◽  
Potential Importance ◽  
Atrial Natriuretic Peptides ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Atrial Natriuretic

The identification of the atrial natriuretic peptides (ANP) as a new hormonal system has provided a new perspective on the mechanisms controlling renal sodium excretion and abnormalities in sodium homeostasis. The present article focuses on the potential importance of ANP (ANF 99–126) in essential hypertension with particular reference to circulating ANP levels and the relationship between the ANP and the renin–angiotensin system in the control of sodium balance and blood pressure. There is now considerable evidence demonstrating that a substantial proportion of patients with essential hypertension have raised circulating ANP levels. Given the known biological actions of ANP, these raised levels point to important compensatory mechanisms. This is further supported by studies during alterations in dietary sodium intake, as sodium restriction highlighted important relationships between ANP and the renin angiotensin system. The potential importance of ANP in essential hypertension is strengthened by recent demonstration of natriuretic and antihypertensive actions associated with small increases in circulating ANP as induced by administration of exogenous ANP. Furthermore, the recent development of orally active inhibitors of ANP metabolism now provides a basis to determine the therapeutic importance of specific manipulation of endogenous ANP levels in patients with essential hypertension.Key words: ANF, essential hypertension, sodium balance.

Blood pressure effects of renin inhibition by human renin antiserum in normotensive marmosets

1984 ◽  
Vol 246 (3) ◽  
pp. F309-F316 ◽  
Author(s):  
J. B. Michel ◽  
J. Wood ◽  
K. Hofbauer ◽  
P. Corvol ◽  
J. Menard
Keyword(s):  
Blood Pressure ◽  
Enzyme Inhibitor ◽  
Renin Angiotensin System ◽  
Pressure Effects ◽  
Sodium Balance ◽  
New World Monkeys ◽  
Common Marmosets ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Human Renin

The effects on blood pressure of an antiserum against pure human kidney renin were studied in conscious and anesthetized (pentobarbital, 24 mg X kg-1 i.p.) small new world monkeys (common marmosets). The antiserum inhibited the enzymatic activity of renin by 50% in a dilution of 1:45,000 in marmoset and 1:50,000 in human plasma. The antiserum (0.2 ml i.v.) decreased blood pressure in conscious marmosets on normal sodium intake by 15 +/- 5 (SD) mmHg and after salt depletion by 31 +/- 13 mmHg. A converting enzyme inhibitor (teprotide, 2 mg X kg-1 i.v.) induced a comparable fall in blood pressure: -16 +/- 10 and -30 +/- 10 mmHg, respectively. Similar effects were observed on blood pressure of anesthetized marmosets. The correlation between pretreatment plasma renin concentration and the maximum fall in blood pressure was significant and identical for the experiments with antiserum and teprotide. These results demonstrate that antisera against human renin can be used for the specific blockade of the renin-angiotensin system in primates. In normotensive marmosets the renin-angiotensin system participates in the maintenance of blood pressure, to a degree depending on the state of sodium balance.

Differential renal effects of cyclooxygenase inhibition in sodium-replete and sodium-deprived dog

1980 ◽  
Vol 239 (4) ◽  
pp. F360-F365 ◽  
Author(s):  
M. Cynthia Blasingham ◽  
Alberto Nasjletti
Keyword(s):  
Blood Flow ◽  
Angiotensin Ii ◽  
Renal Blood Flow ◽  
Renin Angiotensin System ◽  
Receptor Blocker ◽  
Sodium Balance ◽  
Angiotensin System ◽  
Renal Effects ◽  
Renin Angiotensin ◽  
Arterial Blood

We studied the renal effects of the cyclooxygenase inhibitor sodium meclofenamate (M) (5 mg/kg, iv) in the pentobarbital-anesthetized dog that had been maintained on an elevated (100 meq/day) or on a reduced (<5 meq/day) sodium intake, and during the administration of angiotensin II in the sodium-replete dog, or the angiotensin receptor blocker [Sar1–Ala8]angiotensin II in the sodium-deprived dog. In the sodium-replete dog, M did not affect mean arterial blood pressure (MABP), renal blood flow (RBF), glomerular filtration rate (GFR), or urine volume (V), but reduced the urinary excretion of sodium (UNa V) by 47%, and of immunoreactive PGE2 (iPGE2) by 90%. However, in the sodium-replete dog during angiotensin II infusion (3 ng · kg-1 · min-1, iv), M reduced RBF by 35%, GFR by 24%, V by 71%, and iPGE2m by 94%. Similarly, in the sodium-deprived dog M reduced RBF by 34%, GFR by 28%, and iPGE2 excretion by 89%. However, M did not affect RBF or GFR in the sodium-deprived dog during infusion of [Sar1-Ala8]angiotensin II (6 μg · kg-1 · min-1, iv), although iPGE2 excretion was reduced by 84%. This study demonstrates that the effects of M on renal hemodynamics in the dog vary with the state of sodium balance and suggests that a prostaglandin(s) contributes to maintenance of renal blood flow during activation of the renin-angiotensin system. meclofenamate; renal prostaglandins; renin-angiotensin system; receptor blocker; renal hemodynamic and excretory function Submitted on October 17, 1979 Accepted on May 9, 1980

Studies on the Renin-Angiotensin System in a Kininogen-Deficient Individual

1983 ◽  
Vol 65 (2) ◽  
pp. 121-126 ◽  
Author(s):  
Patrick Y. Wong ◽  
Gordon H. Williams ◽  
Robert W. Colman
Keyword(s):  
Angiotensin Ii ◽  
Plasma Renin Activity ◽  
Renin Angiotensin System ◽  
Plasma Renin ◽  
Renin Activity ◽  
Dietary Sodium ◽  
Sodium Balance ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Normal Individuals

1. The physiological responses of the renin-angiotensin system were studied in an individual with kininogen deficiency (patient 1) with absent plasma bradykinin and markedly impaired prekallikrein conversion into kallikrein. After sodium depletion, patient 1 had a low plasma renin activity (1.4 pmol of ANG I h−1 ml−1) and a low angiotensin II concentration (36 pg/ml) compared with values in 11 normal individuals (4.0 ± 0.94 pmol of ANG I h−1 ml−1) and 63 ±6 pg/ml respectively). 2. Unlike normal individuals, in the kininogen-deficient subject there was no significant fall of renin activity or angiotensin II after dietary sodium repletion. Intravenous sodium repletion also failed to further decrease plasma renin activity or angiotensin II. 3. The usual two- to three-fold rise in plasma renin activity and angiotensin II observed in normal subjects on assumption of the upright posture after ingestion of 200 mg of sodium/day failed to occur in the kininogen-deficient individual. 4. These data in vivo are in agreement with observations in vitro that once plasma kallikrein forms it may be important in converting prorenin into renin. In the absence of kininogen, activation of prekallikrein to kallikrein is grossly defective, which may in part account for the diminished response of the renin-angiotensin system to changes in sodium balance and posture.

Sodium Retention Versus Renin–Angiotensin System In Experimental Renal Hypertension

1973 ◽  
Vol 51 (3) ◽  
pp. 238-241 ◽  
Author(s):  
J. F. Liard
Keyword(s):  
Blood Pressure ◽  
Renal Hypertension ◽  
Renin Angiotensin System ◽  
Sodium Balance ◽  
Sodium Retention ◽  
Sodium Depletion ◽  
Dual Nature ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Experimental Renal Hypertension

The relative importance of sodium retention versus the renin–angiotensin pressor response in hypertension caused by constriction of one renal artery and contralateral nephrectomy in the rat was assessed. Attempts were made to lower the blood pressure by changing sodium balance while plasma renin activity was measured. Acute sodium depletion (furosemide) had no measurable effect on the pressure seemingly because activation of the renin–angiotensin system prevented a fall in pressure. However, the pressure decreased rapidly and markedly in response to sodium depletion when the renin-angiotensin system was suppressed by (a) removing the sole remaining kidney after the sodium depletion or (b) pretreating the animals with deoxycorticosterone and salt. These results emphasize the dual nature of the control of blood pressure by the kidney in experimental renal hypertension.

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