排乳 Sound of Higher brain child's cry centers Hypothalamus ⊙ PIH cell Oxytocin neuron Portal system +PIH Antenor Posteror pituitary pitultary Inhibition of prolactin cells is removed Prolactin ↑Oxytocin Milk secretion Milk Smooth muscle ejected contraction Baby Mechanoreceptors suckling in nipple● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● 排 乳