Evidence of increased peripheral catecholamine release in patients with long-standing, untreated essential hypertension.

In 20 middle-aged men with untreated sustained essential hypertension for more than 5 years, both plasma adrenaline and noradrenaline were positively and significantly correlated with blood pressure. In both hypertensives and 19 normotensive control subjects supine arterial adrenaline concentrations were more than twice the venous concentrations consistent with adrenal production of this catecholamine. Adrenaline a--v(arterial-venous)differences(mean +/- SE) were significantly higher in the hypertensive group (82 +/- 15 pg/ml) than in the controls (50 +/- 5 pg/ml) indicating increased release of adrenaline in the hypertensives (P less than 0.05). Similarly, v-a(venous-arterial) differences of noradrenaline were significantly higher in the hypertensive (44 +/- 20 pg/ml) than in the control group (-10 +/- 16 pg/ml) indicating peripheral noradrenaline release in patients with essential hypertension. The findings are compatible with increased forearm noradrenaline and adrenal adrenaline release in these patients with long-standing untreated essential hypertension.