OxytocinOxytocicsVasotocinVasopressinsMilk EjectionSupraoptic NucleusPituitary Gland, PosteriorNeurophysinsUterine ContractionDinoprostMyometriumLabor, ObstetricOrnipressinUterusPregnancyParaventricular Hypothalamic NucleusProgesteroneLactationEstrusHypothalamusLabor, InducedCorpus LuteumHistamine ReleaseCalciumLuteolysisPregnancy, AnimalMaternal BehaviorSheepPair BondSocial BehaviorRats, Sprague-DawleyHormone AntagonistsTocolytic AgentsProstaglandins FEndometriumLypressinRadioimmunoassayPostpartum HemorrhageRats, WistarNeuronsNeurosecretionLabor Stage, ThirdUterine InertiaTime FactorsDose-Response Relationship, Drug