Adiponectin Receptors

Adiponectin exerts its biological effects mainly by binding to two structurally and functionally distinct G protein-coupled receptors, AdipoR1 and AdipoR2 [1]. Opposite to other seven-transmembrane-domain G protein-coupled receptors, AdipoR1 and AdipoR2 are composed of an internal N-terminus and external C-terminus. In animal models, AdipoR1 is expressed ubiquitously (mostly in skeletal muscle) and exhibits a high affi nity for globular adiponectin. AdipoR2 is predominantly expressed in the liver and has an intermediated affi nity for globular and full-length adiponectin. T-cadherin has been proposed to act as a co-receptor for the high-molecular-weight form of adiponectin on endothelial and smooth muscle cells [2].