α-adrenoceptors and benign prostatic hyperplasia:: basic principles for treatment with α-adrenoceptor antagonists

The selective blockade of alpha(1)-adrenoceptors (ARs) is now a well-accepted and widely used treatment for patients presenting with lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH) and bladder outlet obstruction. The sites of action of the currently used alpha(1)-AR antagonists when relieving LUTS have not yet been established, but it seems clear that effects on prostatic as well as non-prostatic tissues are important. alpha(1)-ARs in the bladder, urethra, and vas deferens, on ganglia and nerve terminals, and in the central nervous system (CNS) may all influence LUTS and the clinical effects of alpha(1)-AR antagonists. The relevance of alpha(1)-AR subtype selectivity for the clinical usefulness of existing drug therapy has still not been clarified, but it cannot be dismissed that blockading both alpha(1A)- and alpha(1D)-ARs is necessary for optimal clinical effect. Despite the above uncertainties, there seems to be a consensus that clinically available alpha(1)-AR antagonists provide a safe, effective and generally well-tolerated therapy for patients with LUTS.