Stimulation of maternal behavior after bilateral infusions of ovine (o) PRL (40 ng/side) into the MPOA region of steroid-primed, nulliparous rats. ** P < 0.01 versus vehicle controls. Taken from Bridges, R.S., Numan, M., Ronsheim, P.M., Mann, P.E., Lupini, C.E., 1990. Central prolactin infusions stimulate maternal behavior in steroid-treated, nulliparous female rats. Proceedings of the National Academy of Sciences USA 87(20), 8003–8007, with permission..