Which tissue responds to oxytocin to promote lactation?

• A. Breast
• B. Liver
• C. Skeletal muscle
• D. Pancreas

Answer: (A)

Oxytocin triggers milk ejection by acting on the mammary gland. The tissue that responds to this hormone is breast tissue, specifically the myoepithelial cells surrounding the milk-producing alveoli. When oxytocin binds to receptors on these cells, they contract and squeeze milk into the ducts, enabling let-down. Milk production itself is driven mainly by prolactin, not oxytocin, which is why the other tissues listed (liver, skeletal muscle, pancreas) aren’t the sites of oxytocin’s milk-ejection action.