E-ZE-P 2MG 10 S.G. CAPS

Indication For the treatment of symptomatic BPH and mild to moderate hypertension. Mechanism of action In general a1-adrenergic receptors mediate contraction and hypertrophic growth of smooth muscle cells. a1-Receptors are 7-transmembrane domain receptors coupled to G proteins Gq/11. Three a1-receptor subtypes which share approximately 75% homology in their transmembrane domains have been identified: a1A (chromosome 8) a1B (chromosome 5) and a1D (chromosome 20). Terazosin is the first a1-receptor antagonist to demonstrate selectivity for the a1A-receptor. All three receptor subtypes appear to be involved in maintaining vascular tone. The a1A-receptor maintains basal vascular tone while the a1B-receptor mediates the vasocontrictory effects of exogenous a1-agonists. Activation of a1-receptors activates Gq-proteins which results in intracellular stimulation of phospholipases C A2 and