[3H]-[Thr4,Gly7]OT: a highly selective ligand for central and peripheral OT receptors.

摘要: Oxytocin receptors in rat hippocampal synaptic plasma membranes were compared with mammary gland and uterine oxytocin receptors. For this purpose, a highly specific oxytocic agonist [Thr4,Gly7]oxytocin was tritiated. We demonstrated that ligand labels selectively. Scatchard analyses revealed high affinity for all the investigated, equilibrium dissociation constants between 1.0 2.0 nM. Binding appeared to take place at single population of receptor sites. Competition experiments confirmed arginine vasopressin but also do not discriminate more efficiently vasopressin. This lack specificity is affected by applying different concentrations Mg ions.