[New findings on the use of specific alpha-1 adrenergic blockers in the treatment of high blood pressure]

Abstract

Adrenergic alpha-receptors blockers have been used for a long time in the treatment of hypertension. The use of original non-selective alpha 1-blockers was restricted by the occurrence of undesirable side-effects. Therapeutic interest in alpha-blockers was restored after the discovery of selective adrenergic alpha 1-blockers. Since 1976 when the first selective alpha 1-blocker, prazosine, appeared on the market a number of quinazoline derivatives was developed (terazosine, doxazosine, trimazosine) and non-quinazoline alpha 1-blockers (indoramine, ketanserine, urapidil etc.). Selective alpha 1-blockers normalize the BP by reducing the pathologically raised peripheral vascular resistance without changing the cardiac output. They influence the capacity as well as resistant vascular system and reduce thus the pre-load and after-load. Alpha 1-blockers do not affect, or increase slightly the renal blood flow without altering glomerular filtration. Treatment with selective alpha 1-blockers is associated with a smaller tachycardia than treatment with direct vasodilatating agents or non-selective alpha-blockers. Contrary to saluretics and some beta-blockers, alpha 1-blockers have a favourable effect on plasma lipoproteins, insulin resistance, glucose metabolism and they support the regression of hypertrophy of the vascular wall and the left ventricle. Alpha 1-blockers are effective as monotherapy and when combined with other antihypertensive drugs. They are well tolerated with a small number of undesirable side-effects. Selective alpha 1-blockers reduce the BP in a haemodynamically favourable way and exert a favourable effect on other risk factors of ischaemic heart disease in hypertonic patients.(ABSTRACT TRUNCATED AT 250 WORDS)