The Role of Vascular Capacitance in the Genesis of Essential Hypertension

1976 ◽  
Vol 51 (s3) ◽  
pp. 203s-205s
Author(s):  
M. Ulrych

1. Analysis of relationships between blood volume, vascular capacitance, cardiopulmonary and peripheral blood volumes, labelled albumin disappearance rate, plasma renin activity, blood pressure and age was performed in essential hypertensive males. 2. The results indicate that capacitance bed constriction probably occurs with age in essential hypertension leading to an increase in the product blood volume × vascular capacitance tone even in the presence of low blood volume. 3. A metabolic defect in the venous vascular bed along with an abnormality of regulation of renal sodium excretion is postulated.

1976 ◽  
Vol 51 (s3) ◽  
pp. 211s-213s
Author(s):  
M. Ulrych ◽  
Z. Ulrych

1. Relationships between labelled albumin disappearance rate (LADR), plasma volume, blood volume, plasma renin activity (PRA) and blood pressure (BP) were studied in normotensive control subjects and patients with hypertension of different aetiology and severity. In essential hypertensive patients without complications an inverse linear relationship was found between blood pressure and plasma or blood volume. 2. Very close inverse correlations were found between LADR and PRA in both normotensive subjects and patients with uncomplicated essential hypertension. LADR appears to be an excellent reference standard for PRA. 3. It is postulated that LADR mainly reflects the relation between circulating fluid and vascular capacitance tone. LADR is increased in hypertension and blood volume may still be inappropriately high.


1977 ◽  
Vol 62 (2) ◽  
pp. 209-218 ◽  
Author(s):  
Peter Weidmann ◽  
David Hirsch ◽  
Carlo Beretta-Piccoli ◽  
Francois C. Reubi ◽  
Walter H. Ziegler

1976 ◽  
Vol 51 (s3) ◽  
pp. 177s-180s ◽  
Author(s):  
R. Gordon ◽  
Freda Doran ◽  
M. Thomas ◽  
Frances Thomas ◽  
P. Cheras

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.


1982 ◽  
Vol 12 (1) ◽  
pp. 145
Author(s):  
Soon Kyu Suh ◽  
Sae Wha Yoo ◽  
Soon Chang Park ◽  
Joon Sock Kim ◽  
Kyung Ho Kang ◽  
...  

2010 ◽  
Vol 391 (12) ◽  
Author(s):  
M. David Percival ◽  
Sylvie Toulmond ◽  
Nathalie Coulombe ◽  
Wanda Cromlish ◽  
Sylvie Desmarais ◽  
...  

Abstract Renin is the first enzyme in the renin-angiotensin-aldosterone system which is the principal regulator of blood pressure and hydroelectrolyte balance. Previous studies suggest that cathepsin B is the activator of the prorenin zymogen. Here, we show no difference in plasma renin activity, or mean arterial blood pressure between wild-type and cathepsin B knockout mice. To account for potential gene compensation, a potent, selective, reversible cathepsin B inhibitor was developed to determine the role of cathepsin B on prorenin processing in rats. Pharmacological inhibition of cathepsin B in spontaneously hypertensive and double transgenic rats did not result in a reduction in renal mature renin protein levels or plasma renin activity. We conclude that cathepsin B does not play a significant role in this process in rodents.


1983 ◽  
Vol 244 (1) ◽  
pp. R74-R77 ◽  
Author(s):  
J. Schwartz ◽  
I. A. Reid

The role of vasopressin in the regulation of blood pressure during water deprivation was assessed in conscious dogs with two antagonists of the vasoconstrictor activity of vasopressin. In water-replete dogs, vasopressin blockade caused no significant changes in mean arterial pressure, heart rate, plasma renin activity (PRA), or plasma corticosteroid concentration. In the same dogs following 48-h water deprivation, vasopressin blockade increased heart rate from 85 +/- 6 to 134 +/- 15 beats/min (P less than 0.0001), increased cardiac output from 2.0 +/- 0.1 to 3.1 +/- 0.1 1/min (P less than 0.005), and decreased total peripheral resistance from 46.6 +/- 3.1 to 26.9 +/- 3.1 U (P less than 0.001). Plasma renin activity increased from 12.4 +/- 2.2 to 25.9 +/- 3.4 ng ANG I X ml-1 X 3 h-1 (P less than 0.0001) and plasma corticosteroid concentration increased from 3.2 +/- 0.7 to 4.9 +/- 1.2 micrograms/dl (P less than 0.05). Mean arterial pressure did not change significantly. When the same dogs were again deprived of water and pretreated with the beta-adrenoceptor antagonist propranolol, the heart rate and PRA responses to the antagonists were attenuated and mean arterial pressure decreased from 103 +/- 2 to 91 +/- 3 mmHg (P less than 0.001). These data demonstrate that vasopressin plays an important role in blood pressure regulation during water deprivation in conscious dogs.


1982 ◽  
Vol 46 (9) ◽  
pp. 954-963 ◽  
Author(s):  
YASUHIRO NODA ◽  
KOSHIRO FUKIYAMA ◽  
KENSHI KUMAMOTO ◽  
SHUICHI TAKISHITA ◽  
TERUKAZU KAWASAKI ◽  
...  

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