A short polypeptide hormone, C43H66N12O12S2, released from the posterior lobe of the pituitary gland, that stimulates the contraction of smooth muscle of the uterus during labor and facilitates ejection of milk from the breast during nursing.

• 催产素一种少量多肽荷尔蒙C43H66N12O12S2从脑垂体后叶释放出的，在分娩时使子宫松软肌肉收缩，并在哺乳期加速乳汁从乳房中流出