The 'swift birth' hormone
Oxytocin
A small hormone, just nine amino acids long, made in the brain.
- Size
- 9 amino acids
- Made in
- The hypothalamus, in the brain
- Named
- 1906
- Job
- Childbirth, breastfeeding and bonding
The story
In 1906, British scientist Sir Henry Dale found that an extract from the pituitary gland made the uterus contract. He named the active substance oxytocin, from the Greek for "swift birth".
Almost 50 years later, in 1953, American chemist Vincent du Vigneaud worked out its sequence and then made it from scratch in the lab. It was the first peptide hormone ever made synthetically, and it won him the 1955 Nobel Prize in Chemistry.
Good to know
Oxytocin is famous for its role in childbirth and breastfeeding. Scientists also study its role in social bonding and trust, which is why you'll sometimes hear it called the "love hormone".
Its nine amino acids form a small ring, held closed by a bond between two cysteines. You can see how much it weighs in the calculator.
Did you know?
Henry Dale went on to win a Nobel Prize of his own in 1936, for work on how nerves send signals, not for oxytocin.