Potential future developments in the field of antihypertensive drugs.

Since an understanding of the pathogenesis of essential hypertension is unlikely to be imminent, there is little chance that antihypertensive therapy will become curative in the near future. What progress can be expected in symptomatic therapy? In the past, nearly all major mechanisms involved in the regulation of blood pressure have become targets of antihypertensive drugs; they include the sympathetic neuro-effector system, neuronal substrates of central cardiovascular regulation, the kidney, the renin angiotensin aldosterone system and the vascular smooth muscle cell. Among drugs that influence the function of the sympathetic nervous system, the clinical potential of one mechanism of action has not yet been explored: it is the inhibition of noradrenaline release through stimulation of inhibitory receptors located at the adrenergic nerve terminals of the cardiovascular system (inhibitory presynaptic receptors). Among the multiple presynaptic receptors, dopamine receptors appear to be a particularly interesting target. The not entirely expected activity of angiotensin converting enzyme (ACE) inhibitors in essential hypertension prompted the search for renin inhibitors. Whether interruption of the cascade of the renin angiotensin system at the first reaction step by renin inhibitors, as compared to the interference at the second step by ACE inhibitors, will yield relevant progress in antihypertensive drug therapy remains to be seen.