Essential hypertension: neural considerations.

Abstract

Current evidence suggests that the sympathetic nervous system plays a predominant role in some fraction of essential hypertension. Patients in whom such mechanisms are likely to be operative are young people with mild or labile hypertension. These mechanisms are expressed clinically through orthostatic hypertension, rapid heart rate, modestly elevated cardiac output, and normal or slightly elevated peripheral vascular resistance. The vascular resistance is inappropriately high for the level of cardiac output, and this is reflected in a mildly elevated blood pressure. This evidence carries therapeutic implications and suggests that sympatholytic drugs should be the first line of therapy. An additional pressor mechanism may arise from increased sympathetic activity along renal efferent nerves that impairs sodium excretion and another possible mechanism is stimulation of brain centers through impulses from the kidneys carried in renal afferent nerves.