Ejection of milk from breast is due to?

Ans. a (Oxytocin). (Ref. Guyton physiology 11th ed. 1040)Sr. No.Posterior lobe of pitutary gland secretesFunction1Vasopressin (antidiuretic hormone, ADH)Promotes water retention2OxytocinCauses milk ejection, contraction of pregnant uterusEffect of Oxytocin on the UterusOxytocin in a nine amino acid peptide that is synthesized in hypothalamic neurons and transported down axons of the posterior pituitary for secretion (secreted by the neurohypophysis) that specifically causes uterine contraction.Ejection (or "Let-Down") Process in Milk Secretion--Function of Oxytocin# Milk is secreted continuously into the alveoli of the breasts, but milk does not flow easily from the alveoli into the ductal system and, therefore, does not continually leak from the breast nipples. Instead, the milk must be ejected from the alveoli into the ducts before the baby can obtain it. This is caused by a combined neurogenic and hormonal reflex that involves the posterior pituitary hormone oxytocin.