Purity ~85% (SDS-PAGE). Neurophysin 1 specifically binds oxytocin.Oxytocin causes contraction of the smooth muscle of the uterus and of the mammary gland. Source: Recombinant protein corresponding to aa32-125 from human Oxytocin-neurophysin 1, fused to His-tag at N-terminal and fused to Myc-tag at C-terminal, expressed in E. coli. Molecular Weight: ~14.6kD AA