Wrapping around the alveolus are special myoepithelial cells that squeeze down and push the milk out of the lumen of the alveolus, down the lactiferous ducts, and out one of the pores on the nipple.

腺泡外是一层特殊的肌上皮细胞，会推挤乳汁离开腺泡管腔进入乳腺导管并从乳头的毛孔分泌而出。