Increased arterial catecholamine concentrations in 50-year-old men with essential hypertension

Abstract

In a recent study of 50-year-old men with long-standing, untreated essential hypertension we found increased arterial and venous plasma concentrations and arterial-venous differences of adrenaline (a—v) and noradrenaline (v—a) as compared to a matching normotensive control group. The aim of the present study was to investigate whether men of this age with hypertension of shorter duration and less severity than in the first study might also have increased plasma catecholamines. Twenty-three hypertensive and 17 age-matched normotensive control men were studied. The hypertensive ones had increased supine heart rate (P<0.05), arterial noradrenaline (P<0.01) and adrenaline (P<0.02) whereas venous catecholamines did not differ between the two groups. The a—v differences (means ± SE) of adrenaline (78 ± 14 vs 42 ± 6 ng/l, P<0.05) and the orthostatic adrenaline response (45 ± 9 vs 24 ± 5 ng/l, P<0.05) were increased in the hypertensive compared to the normotensive group. In the hypertensive, the arterial plasma concentrations of the two catecholamines correlated positively (r = 0.71, P<0.001) as did the a—v differences (r = 0.54, P<0.01). The findings are compatible with increased sympathetic-adrenal activity in men with essential hypertension. Arterial and not venous plasma concentrations must be measured to reveal this difference between normotensive control subjects and patients with essential hypertension of intermediate severity and duration.

Key Words:

• adrenaline
• arterial
• blood pressure
• heart rate
• noradrenaline
• sympathetic