Analysis of pancreatic beta-cell receptors binding the sulfanilamide drugs widely used in therapy of type II diabetes, such as glybenclamide, glypizide, and glyclazide, showed that these drugs are characterized by excellent parameters of specific binding to these receptors. The receptors were tested for two parameters: number of binding sites and dissociation constant. Glybenclamide was the most active of the drugs we tested, the other two agents being less active. Binding of these agents was reversible. The problem of identification of the examined receptors of sulfanilamides with K+-ATP-sensitive channels, similarly active conductors of the information transported by the sulfanilamide drugs in the mechanism of insulin secretion, is discussed.