An Investigation into the Pathogenesis of Hypertension in Acromegaly

1977 ◽  
Vol 53 (1) ◽  
pp. 87-91 ◽  
Author(s):  
M. H. Snow ◽  
D. A. Piercy ◽  
Valerie Robson ◽  
R. Wilkinson
Keyword(s):  
Blood Pressure ◽  
Growth Hormone ◽  
Plasma Renin Activity ◽  
Plasma Renin ◽  
Renin Activity ◽  
Exchangeable Sodium ◽  
Endocrine Disease ◽  
Control Subjects ◽  
Normotensive Subjects ◽  
Sodium Overload

1. In 29 patients with acromegaly, plasma renin activity and growth hormone were measured during fasting and recumbency on free diet. Exchangeable sodium was measured in all cases and expressed as a percentage of the expected value on the basis of lean body mass. 2. Twenty-two control subjects without evidence of cardiovascular, renal or endocrine disease were studied in the same way. 3. There was a significant increase in exchangeable sodium and suppression of plasma renin activity in the acromegalic patients in comparison with control subjects. 4. There was a significant positive correlation between exchangeable sodium and plasma growth hormone. 5. Hypertensive acromegalic patients (diastolic blood pressure ≥ 100 mmHg) tend to have a lower (although not significantly so) exchangeable sodium than normotensive subjects. 6. We conclude that (a) suppression of plasma renin activity in acromegaly can be explained by sodium retention, (b) hypersecretion of growth hormone is probably responsible for the increased exchangeable sodium, and (c) sodium overload cannot be directly related to blood pressure but may contribute to the increased occurrence of hypertension in acromegaly.

Solitary Kidney and Ageing as Causes of Low Renin and Aldosterone Concentrations: Relevance to ‘Low-Renin’ Essential Hypertension

1976 ◽  
Vol 51 (s3) ◽  
pp. 177s-180s ◽  
Author(s):  
R. Gordon ◽  
Freda Doran ◽  
M. Thomas ◽  
Frances Thomas ◽  
P. Cheras
Keyword(s):  
Blood Pressure ◽  
Essential Hypertension ◽  
Plasma Renin Activity ◽  
Plasma Volume ◽  
Plasma Renin ◽  
Renin Activity ◽  
Dietary Sodium ◽  
Sodium Restriction ◽  
Normotensive Subjects ◽  
The Mean

1. As experimental models of reduced nephron population in man, (a) twelve men aged 15–32 years who had one kidney removed 1–13 years previously and (b) fourteen normotensive men aged 70–90 years were studied. Results were compared with those in eighteen normotensive men aged 18–28 years and eleven men aged 19–33 years with essential hypertension. 2. While the subjects followed a routine of normal diet and daily activity, measurements were made, after overnight recumbency and in the fasting state, of plasma volume and renin activity on one occasion in hospital and of blood pressure on five to fourteen occasions in the home. Blood pressure was also measured after standing for 2 min and plasma renin activity after 1 h standing, sitting or walking. Twenty-four hour urinary aldosterone excretion was also measured. 3. The measurements were repeated in the normotensive subjects and subjects in (a) and (b) above after 10 days of sodium-restricted diet (40 mmol of sodium/day). 4. The mean plasma renin activity (recumbent) in essential hypertensive subjects was higher than in normotensive subjects. In subjects of (a) and (b) above, it was lower than normotensive subjects, and was not increased by dietary sodium restriction in subjects of (a). 5. The mean aldosterone excretion level was lower in old normotensive subjects than in the other groups, and increased in each group after dietary sodium restriction. 6. Mean plasma volume/surface area was not different between the four groups and in normotensive, essential hypertensive and nephrectomized subjects but not subjects aged 70–90 years was negatively correlated with standing diastolic blood pressure.

Sodium and Renin in the Hypertension of Early Renal Disease

1978 ◽  
Vol 55 (s4) ◽  
pp. 301s-303s ◽  
Author(s):  
S. F. Wong ◽  
M. I. Mitchell ◽  
V. Robson ◽  
R. Wilkinson
Keyword(s):  
Blood Pressure ◽  
Renal Disease ◽  
Plasma Renin Activity ◽  
Plasma Renin ◽  
Renin Activity ◽  
Exchangeable Sodium ◽  
Hypertensive Patients ◽  
Body Build ◽  
Activity Response ◽  
Normal Controls

1. Plasma renin activity, response to saralasin and exchangeable sodium have been measured in 43 patients with early renal disease. 2. Blood pressure was directly proportional to plasma renin activity. However, mean plasma renin activity was lower in patients with renal disease than in normal controls. 3. Blood pressure fell in response to saralasin infusion in proportion to the pre-infusion plasma renin activity. 4. Exchangeable sodium in hypertensive patients with renal disease did not exceed that in normotensive patients in contrast to earlier reports. Discrepancies may arise from the difficulty in interpreting measured exchangeable sodium in relation to body build.

Familial Hypertension and Hormonal Profile, Renal Haemodynamics and Body Fluids of Young Normotensive Subjects

1978 ◽  
Vol 55 (s4) ◽  
pp. 367s-371s ◽  
Author(s):  
G. Bianchi ◽  
G. B. Picotti ◽  
G. Bracchi ◽  
D. Cusi ◽  
M. Gatti ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Plasma Renin Activity ◽  
Plasma Flow ◽  
Renal Plasma Flow ◽  
Plasma Catecholamines ◽  
Plasma Renin ◽  
Significant Negative Correlation ◽  
Renin Activity ◽  
Compensatory Mechanism ◽  
Normotensive Subjects

1. Almost all the factors that may cause a rise in blood pressure are, in turn, influenced by the increase in blood pressure per se. Thus any primary involvement of one or more of these factors in the pathogenesis of essential hypertension must be evaluated before or during the development of hypertension. 2. Young normotensive subjects both of whose parents are hypertensive have a much higher probability of developing hypertension than those whose parents are both normotensive. 3. The following measurements were made in 56 subjects of the first group (both parents hypertensive) and 35 of the second group (both parents normotensive), matched for age, sex and body surface area: renal plasma flow and glomerular filtration rate, using p-aminohippurate and inulin clearance; 24 h urinary excretion of aldosterone, protein and electrolytes; plasma renin activity; plasma volume. Plasma catecholamines and cardiac index were also measured in 26 subjects of the first group and 25 subjects of the second group using a radioenzymic method and echocardiography. 4. All these factors were similar in the two groups except that renal plasma flow was higher in the first group (767·2 ± 30 versus 650·7 ± 17 ml/min, P < 0·01). Plasma renin activity tended to be lower in subjects with a higher renal plasma flow, but there was no significant negative correlation between the two factors. 5. The possibility that the higher renal plasma flow in subjects with a high probability of developing hypertension is a compensatory mechanism for a primary intrarenal defect is discussed.

Reduced Plasma Renin Activity in Essential Hypertension: Effects of Blood Pressure, Age and Sodium

1976 ◽  
Vol 51 (s3) ◽  
pp. 185s-188s ◽  
Author(s):  
G. W. Thomas ◽  
J. G. G. Ledingham ◽  
L. J. Beilin ◽  
A. N. Stott
Keyword(s):  
Blood Pressure ◽  
Essential Hypertension ◽  
Plasma Renin Activity ◽  
Inverse Relationship ◽  
Plasma Renin ◽  
Renin Activity ◽  
Hypertensive Patients ◽  
Significant Inverse Relationship ◽  
Control Subjects ◽  
And Control

1. Supine plasma renin activity and its responsiveness to erect posture and frusemide were reduced in fifty-one patients with essential hypertension, compared with fifty-one age- and sex-matched control subjects. 2. Twenty-four hour urinary sodium excretion was similar in hypertensive patients and control subjects, but after intravenous frusemide hypertensive patients excreted significantly less sodium. 3. A significant inverse relationship between plasma renin activity and diastolic blood pressure was demonstrated in hypertensive patients and in normotensive control subjects. 4. A significant inverse relationship between plasma renin activity and age, independent of blood pressure, was shown in hypertensive patients and control subjects. 5. It is concluded that the reduced renin values found in essential hypertension are, in part, the result of the elevated blood pressure acting on the kidney.

Plasma Catecholamines and Renin Activity in Response to Exercise in Patients with Essential Hypertension

1975 ◽  
Vol 49 (5) ◽  
pp. 511-514
Author(s):  
J. Chodakowska ◽  
K. Nazar ◽  
B. Wocial ◽  
M. Jarecki ◽  
B. Skórka
Keyword(s):  
Blood Pressure ◽  
Essential Hypertension ◽  
Plasma Renin Activity ◽  
Plasma Catecholamines ◽  
Plasma Renin ◽  
Work Load ◽  
Renin Activity ◽  
Plasma Noradrenaline ◽  
Hypertensive Patients ◽  
Control Subjects

1. The effect of physical exercise on blood pressure, plasma catecholamines and plasma renin activity was studied in fourteen patients with essential hypertension and in eight healthy subjects. 2. Resting plasma noradrenaline and adrenaline and plasma renin activity of the hypertensive patients did not differ from those of the control subjects. 3. In response to graded exercise producing successive heart rates of 120, 140 and 160 beats/min, significantly greater increases of blood pressure were found in the patients than in the control subjects. 4. Plasma noradrenaline increased significantly in both groups at all levels of exercise, the responses being significantly greater in the hypertensive patients. 5. The mean arterial blood pressure was significantly correlated with plasma noradrenaline concentration in the control subjects but not in the hypertensive patients. 6. In the hypertensive group plasma adrenaline increased significantly after exercise at all work loads whereas, in the control group, significant increase occurred only at the highest work load. The differences in the response of the two groups were significant at each work load. 7. Plasma renin activity increased significantly after exercise at the heart rate of 120 beats/min, both in the hypertensive patients and in the control subjects. The magnitude of the response was similar in the two groups.

Biochemical Correlates of the Increase in Blood Pressure with Age

1978 ◽  
Vol 55 (s4) ◽  
pp. 377s-379s ◽  
Author(s):  
C. E. Grim ◽  
M. H. Weinberger ◽  
D. P. Henry ◽  
F. C. Luft ◽  
N. S. Fineberg
Keyword(s):  
Blood Pressure ◽  
Plasma Renin Activity ◽  
Sodium Intake ◽  
Plasma Renin ◽  
Normal Subjects ◽  
Renin Activity ◽  
Multiple Correlation Analysis ◽  
Normotensive Subjects ◽  
Relationship Of ◽  
The Relationship

1. Blood pressure, plasma renin activity, plasma aldosterone, urinary noradrenaline during sleep (UNA-S) and several estimates of sodium intake were determined in 379 normotensive subjects (age 13–70) to investigate the relationship of these variables to blood pressure. 2. Blood pressure was correlated with age, weight, plasma renin activity UNA-S, and estimates of sodium intake. These variables were frequently intercorrelated. 3. Multiple-correlation analysis revealed that after removal of the effects of age, blood pressure was related to weight, plasma renin activity, UNA-S and estimates of sodium intake. 4. However, multiple-regression analysis failed to demonstrate an effect of plasma renin activity, UNA-S, or estimates of sodium intake on blood pressure when the effects of age, weight, race and sex were removed. 5. Careful matching of subjects by age, weight, race and sex in studies of blood pressure and biochemical factors in normal subjects is crucial to proper interpretation of such data.

Acute and Chronic Effects of Nifedipine on Plasma Renin Activity and Plasma Adrenaline and Noradrenaline in Controls and Hypertensive Patients

1979 ◽  
Vol 57 (s5) ◽  
pp. 115s-117s ◽  
Author(s):  
L. Corea ◽  
N. Miele ◽  
M. Bentivoglio ◽  
E. Boschetti ◽  
E. Agabiti-Rosei ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Plasma Renin Activity ◽  
Plasma Renin ◽  
Renin Activity ◽  
Sublingual Administration ◽  
Plasma Adrenaline ◽  
Hypertensive Patients ◽  
Long Term Treatment ◽  
Normotensive Subjects

1. Nifedipine, a calcium antagonist drug, was given sublingually (10 mg) to seven normal subjects and 19 patients with essential hypertension. In addition, 12 of the hypertensive subjects then received nifedipine (10 mg thrice daily) for 3 weeks. 2. Sublingual administration of nifedipine in hypertensive patients induced a prompt and sustained reduction of blood pressure, without a significant increase of heart rate; in normotensive subjects blood pressure did not change, and heart rate was significantly increased. After chronic treatment, blood pressure remained reduced and heart rate did not rise. 3. Plasma catecholamines and plasma renin activity increased significantly in normotensive subjects after acute administration. 4. After both acute and chronic administration, only plasma noradrenaline was significantly increased in hypertensive patients; in long-term treatment, it was increased in both the lying and standing positions. 5. Nifedipine is an active antihypertensive drug, which may induce some degree of sympathetic activation.

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