Captopril treatment: inter‐dose variations in renin, angiotensins I and II, aldosterone and blood pressure.

Abstract

1The ability of captopril, 150 mg three times daily by mouth, to effect sustained reduction in plasma angiotensin II, with converse increases in circulating angiotensin I, and in active, inactive and total renin concentrations, has been assessed. 2 During prolonged treatment with captopril alone, and 12 h after the last dose of the drug, plasma angiotensin II remained approximately one-sixth of basal concentrations, while angiotensin I and renin concentrations were proportionately increased. However, further increases in angiotensin I, and in active, inactive and total renin concentrations, were seen 2 and 6 h after the morning dose of 150 mg captopril. 3 Inter-dose variations in plasma aldosterone and blood pressure were not closely related to concurrent variations in the renin-angiotensin system. 4 Arguments are presented for relying on measurements of plasma renin and angiotensin concentrations rather than of renin activity or aldosterone in assessing the effectiveness of converting enzyme inhibition.

The renin‐angiotensin system during converting enzyme inhibition with captopril in patients with severe treatment‐resistant hypertension

“…Measurements of circulating levels of angiotensin I1 by means of a specific and sensitive radioimmunoassay provide the most relevant approach to an understanding of the role of the renin-angiotensin system in the maintenance and/or development of high blood pressure. Further, the introduction of converting enzyme inhibitors makes it possible to quantify the effectiveness of enzyme inhibition by the concomitant reduction in plasma angiotensin I1 concentration and to relate these to the blood pressure response [24].…”

Converting-enzyme inhibitor enalapril (MK421) in treatment of hypertension with renal artery stenosis.

“…Measurements were made of total body and exchangeable sodium and potassium before and during long-term treatment. [2][3][4][5][6][7][8][9][10][11][12][13][14] Data were analysed using repeated measures analysis of variance, with logarithmic transformation where appropriate. Blood pressures were compared at a total of six time points: before dosing and two and six hours later, after three months of enalapril, and at corresponding times before treatment.…”