Rôle of sympathetic nervous system in essential hypertension

Supra-normal supine and stimulated plasma levels of noradrenaline and/or adrenaline, presumably reflecting increased sympatho-adrenal activity, have been found in a proportion of patients with essential hypertension. In established hypertension a disturbed relationship between plasma noradrenaline concentration and pressor response to noradrenaline has been observed. It is suggested that sympathetic nervous activity and pressor response to noradrenaline together form an important determinant of the arterial blood pressure level.