Glucagon receptor

The glucagon receptor is a 62 is_associated_with::kDa is_associated_with::protein that is activated by is_associated_with::glucagon and is a member of the class B is_associated_with::G-protein coupled family of receptors, coupled to G alpha i, Gs and to a lesser extent G alpha q. Stimulation of the receptor results in activation of is_associated_with::adenylate cyclase and increased levels of is_associated_with::intracellular cAMP. In humans, the glucagon receptor is encoded by the GCGR is_associated_with::gene.

Glucagon receptors are mainly expressed in is_associated_with::liver and in is_associated_with::kidney with lesser amounts found in is_associated_with::heart, is_associated_with::adipose tissue, is_associated_with::spleen, is_associated_with::thymus, is_associated_with::adrenal glands, is_associated_with::pancreas, is_associated_with::cerebral cortex, and is_associated_with::gastrointestinal tract.

Structure
The 3D crystallographic structures of the seven transmembrane helical domain (7TM) and the extracellular domain (ECD) of the glucagon receptor have been determined.

Clinical significance
A is_associated_with::missense mutation in the GCGR gene is associated with is_associated_with::diabetes mellitus type 2.

Inactivating is_associated_with::mutation of glucagon receptor in humans causes resistance to is_associated_with::glucagon and is associated with pancreatic alpha cell is_associated_with::hyperplasia, is_associated_with::nesidioblastosis, is_associated_with::hyperglucagonemia, and pancreatic is_associated_with::neuroendocrine tumors.