Peter King

The ACTH Receptor and Its Mutations

ACTH stimulates steroidogenesis by acting on a single highly specific cell surface receptor in the adrenal cortex. ACTH also has weaker affinity for all the other four members of the melanocortin receptor family, which are expressed in a variety of tissues. The principal endogenous agonists for these other receptors are α- and γ- melanocyte stimulating hormones (α -and γ- MSH), but these peptides are unable to bind to the ACTH receptor. This chapter aims to describe the characterization of this receptor prior to its cloning in 1992 and the subsequent studies of receptor regulation and function. Finally, the defects of this receptor in human disease are described.