Histidine analogues of oxytocin and vasopressin as efficient ligands for Zn2+ ions - Potentiometric and NMR studies

We have characterized the interaction between the Zn2+ ions and the histidine analogues of oxytocin and arginine-vasopressin. Potentiometric methods were used for the determination of the stoichiometry of the complexes formed and the calculation of their stability constants. The NMR measurements revealed detailed structures of the complexes and confirmed the binding mode at physiological pH.