Chimeric relaxin peptides highlight the role of the A-chain in the function of H2 relaxin

► Chimeric peptides combining H2 relaxin-B/INSL peptides-A have been synthesized. ► The peptides demonstrate reduced activity highlighting the importance of the A-chain. ► A-chain chimeras can be produced with receptor specificity. ► H2 relaxin chimeric peptides may be templates for specific RXFP1 agonist development.