Plasma Renin Levels and Systemic Haemodynamics in Essential Hypertension

1977 ◽  
Vol 52 (6) ◽  
pp. 591-597 ◽  
Author(s):  
R. Fagard ◽  
A. Amery ◽  
T. Reybrouck ◽  
P. Lijnen ◽  
L. Billiet ◽  
...  

1. Plasma renin concentration, intra-arterial pressure, cardiac output and total peripheral resistance have been studied in 50 patients with essential hypertension and normal renal function. 2. Total peripheral resistance and plasma renin were negatively correlated (r = −0·45), indicating that ‘high-renin’ essential hypertension is not necessarily associated with arteriolar vasoconstriction. 3. The inverse relation between mean arterial pressure and plasma renin (r = −0·46) suggests a role for the renal baroreceptor mechanism in the suppression of renin in ‘low-renin’ hypertension. 4. Cardiac output was positively related to plasma renin concentration (r = +0·42). 5. Multiple regression analysis indicates that the described relationships were independent of age.

1971 ◽  
Vol 41 (3) ◽  
pp. 219-231 ◽  
Author(s):  
M. A. D. H. Schalekamp ◽  
X. H. Krauss ◽  
M. P. A. Schalekamp-Kuyken ◽  
G. Kolsters ◽  
W. H. Birkenhäger

1. In twenty-two patients representing different stages of benign essential hypertension, hyperosmotic saline was administered intravenously. Determinations of intra-arterial pressure, renal plasma flow, glomerular filtration rate and plasma renin concentration were carried out before and, in the majority, also during and after saline infusion. Changes in cardiac output were followed in ten patients. Plasma volume and extracellular volume were determined in the control period only, although haemodilution was assessed by haematocrit readings. 2. Excess of sodium excretion showed a wide range and was related to the patient's age, as well as to a set of parameters reflecting intrarenal pressure patterns; hypernatriuresis consistently occurred in older patients, in whom renal vascular resistance and nitration fraction were elevated and plasma renin was suppressed. It could not be clarified whether hypernatriuresis together with renin suppression were determined by intrarenal pressure relationships or by an independent age-related factor in the hypertensive patient. 3. Excess of sodium excretion was not related to increments in arterial pressure, cardiac output, renal blood flow or glomerular filtration rate. 4. Plasma renin concentration failed to show consistent changes after hyperosmotic saline infusion. 5. It is concluded that natriuresis is not mediated by changes in the activity of the renin-angiotensin system. Hypernatriuresis appears to be a feature of progressive benign hypertension.


1979 ◽  
Vol 57 (s5) ◽  
pp. 359s-362s ◽  
Author(s):  
P. Van Brummelen ◽  
A. Man In 't Veld ◽  
M. A. D. H. Schalekamp

1. Blood pressure, systemic haemodynamics, plasma volume, renin and aldosterone were measured during placebo treatment and after 1, 4 and 12 weeks of hydrochlorothiazide in 13 patients with uncomplicated essential hypertension. Nine of these patients were also studied after 24 and 36 weeks of treatment. 2. Mean arterial pressure was lowered significantly during hydrochlorothiazide treatment. In seven patients the fall in mean arterial pressure was greater than 10% (responders); four of these were studied for 36 weeks. The remainder were considered non-responders. 3. Hydrochlorothiazide lowered cardiac output. The maximal decrease was observed after 12 weeks of treatment (P < 0·01). In responders this was followed by a return to pretreatment values and a significant decrease in total peripheral resistance, whereas in non-responders cardiac output remained reduced and total peripheral resistance was permanently elevated. 4. Changes in plasma volume, renin and aldosterone were not significantly different in responders and non-responders although non-responders tended to show a greater degree of plasma volume depletion and a more pronounced increase in plasma aldosterone. 5. Thus it is unlikely that the initial decrease in cardiac output is an important determinant of the long-term haemodynamic effect of thiazide diuretics.


1979 ◽  
Vol 57 (s5) ◽  
pp. 437s-439s ◽  
Author(s):  
F. H. Messerli ◽  
J. G. R. Decarvalho ◽  
Barbara Christie ◽  
E. D. Frohlich

1. Six patients with borderline hypertension underwent training in exteroceptive biofeedback (BFB) in order to increase or decrease arterial pressure. 2. Systemic haemodynamics, intravascular volume and peripheral renin activity were determined before, during and after training sessions. 3. BFB training resulted in a significant reduction in mean arterial pressure (from 116 ± 4·6 to 101 ± 2·5 mmHg) mediated through a fall in total peripheral resistance; cardiac output, heart rate, intravascular volume and plasma renin activity remained unchanged. 4. In contrast, the increase or decrease of arterial pressure that occurred during BFB training was produced predominantly through changes in cardiac output and heart rate respectively, whereas total peripheral resistance under these circumstances remained unaffected. 5. The haemodynamic effects of BFB seem remarkably similar to the immediate or chronic effects of β-adrenoreceptor blockade, initially producing a fall in cardiac output followed by a reduced arterial pressure associated with a decreased total peripheral resistance.


1983 ◽  
Vol 61 (2) ◽  
pp. 149-153 ◽  
Author(s):  
Charles D. Ciccone ◽  
Edward J. Zambraski

Eight adult Yucatan miniature swine were implanted with deoxycorticosterone acetate (DOCA) impregnated silicone strips (100 mg∙kg−1). After 16 weeks of DOCA treatment mean arterial pressure (MAP) increased to 183 ± 4 mmHg (1 mmHg = 133.322 Pa). In four normal animals arterial pressure was 126 ± 8 mmHg. The increase in MAP in the DOCA animalas was due to an elevated total peripheral resistance (TPR) with cardiac output remaining normal. In tests with conscious animals, phenoxybenzamine (1 mg∙kg−1) significantly decreased arterial pressure via a selective decrease in TPR. Neither meclofenamate, metoprolol, nor captopril affected MAP in these DOCA hypertensive animals. Dose–response curves to exogenous norepinephrine and angiotensin II revealed that the DOCA animals had an increased pressor sensitivity to both of these agents. These data suggest that in the DOCA hypertensive Yucatan swine an increase in alpha adrenergic activity and (or) an increase in smooth muscle responsiveness to circulating catecholamines is responsible for the increase in blood pressure as a result of an increase in total peripheral resistance.


1987 ◽  
Vol 252 (5) ◽  
pp. H894-H899 ◽  
Author(s):  
Y. W. Chien ◽  
E. D. Frohlich ◽  
N. C. Trippodo

To examine mechanisms by which administration of atrial natriuretic peptide (ANP) decreases venous return, we compared the hemodynamic effects of ANP (0.5 microgram X min-1 X kg-1), furosemide (FU, 10 micrograms X min-1 X kg-1), and hexamethonium (HEX, 0.5 mg X min-1 X kg-1) with those of vehicle (VE) in anesthetized rats. Compared with VE, ANP reduced mean arterial pressure (106 +/- 4 vs. 92 +/- 3 mmHg; P less than 0.05), central venous pressure (0.3 +/- 0.3 vs. -0.7 +/- 0.2 mmHg; P less than 0.01), and cardiac index (215 +/- 12 vs. 174 +/- 10 ml X min-1 X kg-1; P less than 0.05) and increased calculated resistance to venous return (32 +/- 3 vs. 42 +/- 2 mmHg X ml-1 X min X g; P less than 0.01). Mean circulatory filling pressure, distribution of blood flow between splanchnic organs and skeletal muscles, and total peripheral resistance remained unchanged. FU increased urine output similar to that of ANP, yet produced no hemodynamic changes, dissociating diuresis, and decreased cardiac output. HEX lowered arterial pressure through a reduction in total peripheral resistance without altering cardiac output or resistance to venous return. The results confirm previous findings that ANP decreases cardiac output through a reduction in venous return and suggest that this results partly from increased resistance to venous return and not from venodilation or redistribution of blood flow.


1958 ◽  
Vol 194 (2) ◽  
pp. 268-274 ◽  
Author(s):  
E. M. Krieger ◽  
W. F. Hamilton

Seventeen dogs, kept in excellent clinical condition by means of peritoneal lavage, were studied before and after unilateral and bilateral nephrectomy. Heart rate, cardiac output, arterial pressure and total peripheral resistance were measured by the pulse contour method, validated for cardiac output against the dye injection method in the renoprival state. These same measurements were made at the peak of the pressure response to a battery of pressor stimuli including epinephrine, levarterenol, central vagus stimulation and ganglionic stimulation. Twelve normal dogs were subjected to insulin glucose infusion, reducing serum potassium levels below normal, and given the same cardiovascular reactivity tests. The resting hemodynamics of the nephrectomized animals was quite abnormal though the arterial pressure was normal. After both unilateral and bilateral nephrectomy the total peripheral resistance was significantly reduced and the flow greatly increased. In response to pressor stimuli there was an increase in arterial pressure and resistance and a reduction in flow. These changes were significantly augmented in the renoprival state but not after unilateral nephrectomy. The responses to pressor stimuli were greatly diminished by lowered serum potassium levels in 1 nephrectomized dog and in 12 normal dogs. The effect of the change in potassium levels was diminished by vagotomy and ganglionic blockade.


1981 ◽  
Vol 61 (6) ◽  
pp. 663-670 ◽  
Author(s):  
W. P. Anderson ◽  
P. I. Korner ◽  
J. A. Angus ◽  
C. I. Johnston

1. Mild, moderate and severe renal artery stenosis was induced in uninephrectomized conscious dogs by inflating a renal artery cuff to lower distal pressure to 60, 40 or 20 mmHg respectively. The renal artery was narrowed progressively over the next 3 days by further inflation of the cuff to relower the distal renal artery pressure to the initial values. 2. Graded progressive stenosis produced graded progressive rises in blood pressure, plasma renin activity and total renal resistance to flow over the 3 day period, followed by a return to control values 24 h after cuff deflation. 3. The rise in total renal resistance to flow was almost entirely due to the stenosis, with only small changes occurring in renal vascular resistance. 4. in moderate and severe stenosis cardiac output did not alter significantly and thus increases in blood pressure were due to increases in total peripheral resistance. in these groups the resistance to blood flow of the stenosis accounted respectively for about 36 and 26% of the rises in total peripheral resistance. Vasoconstriction of the other non-renal vascular beds accounted for the remainder of the increase in total peripheral resistance. 5. in mild stenosis the changes in both cardiac output and total peripheral resistance were variable and not statistically significant. in this group the rise in stenosis resistance was compensated by vasodilatation of the non-renal vascular beds. 6. in all groups rises in plasma renin activity and blood pressure correlated with the haemodynamic severity of the stenosis. 7. Thus the resistance to blood flow of the moderate and severe renal artery stenoses accounted for one-quarter to one-third of the increases in total peripheral resistance. The remainder of the increase in total peripheral resistance was due to vasoconstriction of nonrenal beds.


1990 ◽  
Vol 68 (3) ◽  
pp. 384-391 ◽  
Author(s):  
Carl F. Rothe ◽  
A. Dean Flanagan ◽  
Roberto Maass-Moreno

We tested the hypothesis that the changes in venous tone induced by changes in arterial blood oxygen or carbon dioxide require intact cardiovascular reflexes. Mongrel dogs were anesthetized with sodium pentobarbital and paralyzed with veruronium bromide. Cardiac output and central blood volume were measured by indocyanine green dilution. Mean circulatory filling pressure, an index of venous tone at constant blood volume, was estimated from the central venous pressure during transient electrical fibrillation of the heart. With intact reflexes, hypoxia (arterial Pao2 = 38 mmHg), hypercapnia (Paco2 = 72 mmHg), or hypoxic hypercapnia (Pao2 = 41; Paco2 = 69 mmHg) (1 mmHg = 133.32 Pa) significantly increased the mean circulatory filling pressure and cardiac output. Hypoxia, but not normoxic hypercapnia, increased the mean systemic arterial pressure and maintained the control level of total peripheral resistance. With reflexes blocked with hexamethonium and atropine, systemic arterial pressure supported with a constant infusion of norepinephrine, and the mean circulatory filling pressure restored toward control with 5 mL/kg blood, each experimental gas mixture caused a decrease in total peripheral resistance and arterial pressure, while the mean circulatory filling pressure and cardiac output were unchanged or increased slightly. We conclude that hypoxia, hypercapnia, and hypoxic hypercapnia have little direct influence on vascular capacitance, but with reflexes intact, there is a significant reflex increase in mean circulatory filling pressure.Key words: cardiovascular reflex, vascular capacitance, hypoxia, hypercapnia, mean circulatory filling pressure, venoconstriction.


1976 ◽  
Vol 51 (s3) ◽  
pp. 525s-526s
Author(s):  
H. Æ. Jensen ◽  
K. Rasmussen ◽  
N. Mosbæk

1. The β1-adrenoreceptor-blocking agent atenolol was studied in the treatment of twelve out-patients with essential hypertension. 2. With a mean dose of 110 mg of atenolol daily (range 75–200 mg/day) we observed a pronounced decrease in blood pressure. 3. Only minimal side effects were seen. 4. Cardiac output decreased from 4·6 to 3·4 l/min during treatment. This decrease did not correlate with the decrease in blood pressure but correlated well with the changes in calculated total peripheral resistance.


1975 ◽  
Vol 49 (4) ◽  
pp. 353-358 ◽  
Author(s):  
P. L. Padfield ◽  
M. E. M. Allison ◽  
J. J. Brown ◽  
A. F. Lever ◽  
R. G. Luke ◽  
...  

1. Intravenous frusemide produced in normal subjects a prompt rise of plasma renin concentration which correlated with urinary sodium. 2. The renin response to frusemide was suppressed in patients with primary hyperaldosteronism. 3. In patients with low-renin hypertension and normal renin essential hypertension, the renin response to frusemide was similarly suppressed. 4. Suppression of the renin response to frusemide is therefore a feature of hypertension not confined to patients with primary hyperaldosteronism and low-renin hypertension. 5. Thus low-renin hypertension does not appear to constitute a distinct diagnostic entity. 6. It is suggested that suppression of the renin response is part of a long-term renal adaptation to high blood pressure.


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