Britannica Sources used in this answer

Which hormones are released into the bloodstream from the posterior pituitary gland?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

human endocrine system The principal glands of the female and male human endocrine systems.

The posterior pituitary gland releases two primary hormones into the bloodstream:

Vasopressin: Also known as antidiuretic hormone (ADH), this hormone regulates blood pressure and helps the body conserve water by increasing the reabsorption of water in the kidneys.12
Oxytocin: This hormone stimulates uterine contractions during labor and facilitates milk ejection during breast-feeding.13

Although these hormones are secreted from the posterior pituitary, they are actually synthesized in the hypothalamus within the supraoptic and paraventricular nuclei. From there, they are transported through axons and stored in the posterior pituitary until nerve signals trigger their release into the general circulation.14