REVISION DE TEMAS CARDIOLOGICOS. FARMACOS VASODILATADORES QUE ACTUAN ESTIMULANDO A LA GUANILATO CICLASA EN EL MUSCULO LISO VASCULAR

Many exogenous and endogenous vasodilator substances produce their effects by stimulation of guanylate cyclase in vascular smooth muscle and increasing cyclic 3',5' - guanosin monophosphate (cGMP) levels. Activation of such enzyme leads to vasodilatation. Possibly as a consequence of a change in the pattern of protein phosphorylation, including dephosphorylation of the light chain myosin and of a decrease in the bioavailability of free calcium. Guanylate cyclase exists in two different forms in the vascular smooth muscle cells: a cytosolic (soluble) and the other associated to membranes (particulate). The nitrovasodilators and vasodilators with endothelium dependent activity, act by main stimulation of the soluble guanylate cyclase, while the atrial natriuretic factor acts specifically on the particulate form of the enzyme. Guanylate cyclase represents the final path in the vasodilation induced by diverse endogenous and exogenous substances; an aspect that has created a great interest among investigators due to its possible physiological, physiopathological and therapeutic implications. The more relevant aspects related with the mechanism of action of this numerous group of drugs are deeply analyzed in the present review.