[Beta 3-receptors: incidence and properties, possible clinical significance].

Beta 3-adrenoceptors is a term used for atypical beta-adrenoceptors which do not fit into either the beta 1- or beta 2-receptor as classified by pharmacological methods. The receptor has been cloned and is thus also genetically defined. Beta 3-adrenoceptors appear to be widely distributed. Until now their importance has been based on studies using agonists with high potency, but yet not selective for beta 3-adrenoceptors. The distribution and functional importance in humans are unclear, and will probably not be clarified before selective antagonists and labelled ligand are developed. Agonists for the beta 3-adrenoceptors may be of clinical value in the treatment of obesity, non-insulin dependent diabetes mellitus, gastrointestinal disorders like irritable colon, inflammatory lung diseases and depression.