Resumo

CONTRERAS, F et al. Receptores Sur y Sulfonilureas en el tratamiento de la Diabetes Mellitus Tipo 2. AVFT [online]. 2002, vol.21, n.2, pp.148-155. ISSN 0798-0264.

The sulfonylureas are well-known insulin secretagogues widely used as oral hypoglycemic agents in the treatment of type 2 diabetes mellitus. Recent studies have revealed that their principle target is the sulfonylurea receptor, a component of the ATP-sensitive potassium channel (K_-ATP). Closure of the K_+-ATP channel causes membrane depolarization which, in turn, triggers calcium influx through voltage-gated Ca²⁺ channels, and thereby stimulates the exocytosis of insulin-containing secretory granules. K_{+ - ATP} channels are formed from KIR6, 2 and sulfonylurea receptor (SUR) subunits. KIR6, 2 forms the channel pore, while the sulfonylurea receptor acts as a regulatory subunit. Three subtypes of SURs have been recognized to date: pancreatic type (SUR1), the inhibition of which facilitates insulin secretion; cardiac type (SUR2A), which provides myocardial protection; and vascular smooth muscle type (SUR2B), which plays a role in vasorelaxation.

Palavras-chave : Type 2 diabetes; Oral hypoglycemic; Receptor SUR; Sulfonylureas.