G protein-coupled receptors as regulators of energy homeostasis.

G protein-coupled receptors (GPCRs) are versatile regulators of physiological processes. They are also important drug targets. Many of the molecules controlling energy homeostasis act through GPCRs. This article summarizes the regulators of energy homeostasis in the central nervous system: those secreted by the gastrointestinal peptides and those secreted by the endocrine pancreas. Some examples of orphan GPCRs are also given. The regulation of energy homeostasis is conserved in other mammals, including those species relevant in veterinary medicine, and fish. Finally, the genetics of human obesity is briefly summarized. Genetic susceptibility in the current obesogenic environment is likely causing the obesity pandemic. A better understanding of the regulation of energy homeostasis will lead to novel pharmacotherapy for obesity treatment.