Oxyntomodulin (human, mouse, rat) (trifluoroacetate salt) (Synonyms: Glicentin (33-69), Proglucagon (33-69))

Oxyntomodulin is a peptide hormone involved in regulation of food intake, energy expenditure, and glucose metabolism. It is produced in gut endocrine L-cells via post-translational processing of preproglucagon by prohormone convertase 1/3 following nutrient uptake. Oxyntomodulin is an agonist of the glucagon-like peptide-1 receptor (GLP-1R) and the glucagon receptor (GCGR; IC50s = 4.3 and 355 nM for rat GCGR and GLP-1R, respectively). It is selective for GCGR and GLP-1R over GLP-2R and glucose-dependent insulinotrophic peptide receptor (GIPR), as it stimulates cAMP formation in BHK cells expressing rat GCGR and GLP-1R when used at concentrations of 10 or 100 nM, but has no effect on cells expressing rat GLP-2R or GIPR at either concentration. Oxyntomodulin also stimulates cAMP formation in CHO cells expressing mouse GLP-1R and GCGR (EC50s = 2.5 and 6.2 nM, respectively). In vivo, oxyntomodulin reduces refeeding in 24-hour fasted rats when injected intracerebroventricularly or into the paraventricular nucleus (PVN) of the hypothalamus at doses of 3 and 1 nmol, respectively. Oxyntomodulin (50 nmol/kg twice per day for 7 days) reduces cumulative daily food intake and rate of body weight gain in rats.