AgRP, physiological role of an inverse agonist

Abstract The melanocortin (MC) system distinguishes itself by the presence of both endogenous agonists—melanocortins as well as endogenous inverse agonists, namely agouti and agouti-related protein (AgRP). The melanocortin system plays an important role in the regulation of pigmentation and body weight. Endogenous inverse agonists provide a means of fine-tuning physiological processes. Disturbances in the balance between melanocortin receptor constitutive activity, melanocortins, and AgRP may contribute to susceptibility for disorders in energy balance (obesity and anorexia).