Counteracting the sympathetic nervous system in essential hypertension

Purpose of review: This paper will provide an up-to-date overview of the adrenergic effects of the different classes of antihypertensive drugs in uncomplicated hypertension, as well as in hypertension associated with obesity, renal failure, diabetes or congestive heart failure. Recent findings: Animal and human studies unequivocally show that sympathetic activation characterizes the hypertensive state and participates in the development, maintenance and progression of elevated blood pressure values. Evidence has also been provided that elevated sympathetic cardiovascular influences are involved in the pathogenesis of left ventricular hypertrophy, vascular hypertrophy and atherogenesis, as well as in the occurrence of metabolic disarray (i.e. metabolic syndrome, hypercholesterolemia, hyperinsulinemia and insulin resistance), which frequently accompany the hypertensive state. Antihypertensive drugs with confirmed sympathoinhibitor effects are represented by beta-blockers, angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers. In the case of the latter two classes of antihypertensive compounds the sympathoinhibitory effects have been shown to be associated with beneficial metabolic and cardiovascular effects, a finding that supports the use of these drugs in complicated hypertension. Summary: Investigation of the adrenergic effects of antihypertensive drugs has had a significant impact on cardiovascular pharmacology and hypertension treatment. Although remarkable progress has been made on this topic in recent years, future studies aimed at assessing the sympathetic effects of combination drug treatment will be helpful in improving the clinical use of the association of two or more drugs in hypertension treatment.