Secreção de insulina: envolvimento e importância do cálcio

Abstract

This review of literature focuses on aspects of the involvement and importance of calcium in insulin release, dealing initially with the need of this ion for the insulinotropic action of inumerable secretogogues. This need has been shown under various experimental conditions, in vitro and in vivo, by several methodological approaches. It also treats aspects of calcium compartmentalization in beta cells, pointing out the involvement of a glycemic state in the organism in determining rearrangement in its distribution among the compartments. Finally, based on the notion that primary event which directs insulin release is the increase of the ionized calcium level in the beta cell cytosol, it focuses on the specific cytophysiological function of this cation as the trigger of the microtubular contractile process and/or as the deleter of electrical charges in the beta cell.