CONCLUSION
We have developed two new radioligands (an agonist and an antagonist) for the GLP-2R; both with high affinity to the human, rat and mouse GLP-2R. With these, we show differential binding kinetics of agonist and antagonist to the GLP-2R, and confirm GLP-2R expression at the protein level in the GI tract’s SEMFs and in the pancreatic islet cells. Moreover, we demonstrate cross-activity with -binding and -activity of GLP-2 within the GLP-1R system. These observations are of importance for tissue localization and structural characterization for not only the GLP-2R, but also for other class B1 GPCRs.