[Effect of coffee on blood pressure and activity renin-angiotensin- aldosterone system and catecholamines concentration in patients with essential hypertension].

The purpose of this study was to investigate whether the renin-angiotensin-aldosterone system activity RAAA or plasma catecholamines concentrations and blood pressure are related to distinct patterns of drinking one cup of coffee in hypertensive patients with low or normal plasma renin activity. Plasma renin activity and enzyme converting angiotensin I to angiotensin II activity and serum concentration of aldosterone and catecholamines were measured by radioimmunoassay. Blood pressure was measured by ambulatory monitoring. Our data suggest that drinking one cup of coffee caused after 60 min, to 2 hours elevated systolic and after 60 min diastolic pressure, only in hypertensive patients, with low RAAA habitually drinking coffee. Hypertensive patients with normal RAAA, habitually drinking coffee, after drinking one cup of coffee had elevation only of diastolic blood pressure from 60 min to 120 min after drinking, but systolic blood pressure did not elevate. Plasma catecholamines and aldosterone concentrations, blood renin activity and enzyme converting angiotensin I to angiotensin II activity were not elevated in hypertensive patients with low or normal RAAA after drinking one cup of coffee.