Comparison of binding affinities of a series of oxytocin analogues to uterine and mammary gland receptors and their biological potencies
The affinity of 12 oxytocin analogues of similar structure but differences in conformational freedom and agonistic and antagonistic properties to receptors in guinea pig uterus and rat mammary gland membrane preparations was determined by competitive binding experiments using tritiated oxytocin. The values obtained for the apparent dissociation constant K D were compared to the values of biological activities from classical pharmacological tests ( uterotonic test in vitro and galactogogic test in vivo).