AGONIST AND ANTAGONIST ACTIVITIES OF PEPTIDES RELATED TO 26RFA, THE LAST MEMBER OF THE RFAMIDE PEPTIDE SUPERFAMILY

摘要

The term RFamide-related peptides (RFRPs) designates a family of biologically active peptides that possess the common signature Arg-Phe-NH2 at their C-terminal extremity . 26RFa, a novel RFRP characterized in our laboratory, is the endogenous ligand of the orphan receptor GPR103. The structure of 26RFa has been strongly preserved from amphibians to mammals , indicating that this peptide subserves important biological functions. The genes encoding the 26RFa precursor and GPR103 are both actively expressed in hypothalamic nuclei involved in the control of energy homeostasis , suggesting that 26RFa may regulate feeding behavior. Indeed, icv administration of 26RFa induces a potent orexigenic effect in mouse. It has been recently shown that GPR103-deficient mice exhibit a kyphotic hump and suffer from osteopenia. Analysis of the human