Oxytocin: What It Is & What It Does
A small hormone your body makes. It acts on nerve cells in the brain and is studied for its part in social behaviour, which is why people call it the love hormone.
In short
Oxytocin is a hormone your body makes, and a very small one, only nine building blocks long. It acts on nerve cells inside the brain, and most of the research on it looks at social behaviour. That is where the love hormone nickname comes from. Pepcore supplies oxytocin as a lyophilised powder at 10 mg per vial, with a batch number on every one.
Related peptides. Kisspeptin-10 · PT-141 · Mixing guide
What does oxytocin do?
The short answer.
Oxytocin acts on nerve cells inside the brain. Most of the research on it looks at social behaviour, which is why people call it the love hormone.
It is also released into the blood, where it acts on muscle tissue. That effect is how it was discovered, over a century ago.
Where it came from
A short history.
It was found in 1906, when an English scientist showed that an extract from the pituitary gland had a strong effect on muscle tissue. Working out what the active ingredient actually was took another forty years.
In 1953 an American chemist, Vincent du Vigneaud, worked out the order of the nine building blocks and then built the molecule from scratch. It was the first hormone of its kind anyone had ever made in a laboratory, and it behaved like the real thing. He won the Nobel Prize for it in 1955.
Easier ways to make it followed within a few years, which is why laboratories have been able to get hold of it ever since.
The numbers
What is in the vial.
| Name | Oxytocin |
| Building blocks | 9 amino acids, formed into a small loop |
| Molecular formula | C₄₃H₆₆N₁₂O₁₂S₂ |
| Molecular weight | ~1007.19 g/mol |
| CAS number | 50-56-6 |
| Purity | ≥ 99% HPLC |
| Supplied as | Lyophilised powder, 10 mg |
| Shipped from | The Netherlands, within the EU |
Sources
Where the above comes from. Titles are the originals, each links to PubMed.
Bodanszky M et al. · 1959 · Nature
Synthesis of oxytocin by the nitrophenyl ester method
Gimpl G et al. · 2001 · Physiological Reviews
The oxytocin receptor system: structure, function, and regulation
Jones C et al. · 2017 · Dialogues in Clinical Neuroscience
Oxytocin and social functioning
Jurek B et al. · 2018 · Physiological Reviews
The Oxytocin Receptor: From Intracellular Signaling to Behavior
Wiśniewski K · 2019 · Methods in Molecular Biology
Design of Oxytocin Analogs
Froemke RC et al. · 2021 · Annual Review of Neuroscience
Oxytocin, Neural Plasticity, and Social Behavior
Storage and mixing
The loop is the fragile part.
Keep the dry powder cold. At -20 °C it lasts a long time, and a normal fridge is fine for short periods. To mix it, add bacteriostatic water slowly down the inside wall of the vial. Never onto the powder, and never shake it. Roll it gently until it dissolves.
One link holds the loop shut, and shaking or repeated freezing is how that link breaks. Once it breaks the shape is gone, and the shape is the whole point. Our mixing guide goes through it step by step, and the peptide calculator works out the concentration.
Frequently asked
What comes up most often.
What is oxytocin?
A hormone your body makes, only nine building blocks long. It acts on nerve cells inside the brain, and most of the research on it looks at social behaviour. All Pepcore products are for laboratory research only.
Why is it called the love hormone?
Because of the brain research. Oxytocin turns up in work on social behaviour, and the press shortened that to the love hormone. It is a nickname, not a finding.
Why is the powder white?
Colour usually comes from a metal, such as the copper in GHK-Cu. Oxytocin has no metal in it, so the freeze-dried powder is white. The vial holds 10 mg by weight, which can look like very little.
How do I store and mix it?
Keep the dry powder cold, at -20 °C for the long term. Add bacteriostatic water slowly down the inside wall of the vial, never straight onto the powder, and never shake it. Avoid freezing and thawing it over and over. The peptide calculator works out concentrations.
Oxytocin at Pepcore
Lyophilised powder, 10 mg per vial, ≥ 99% HPLC purity, certificate of analysis on request. Shipped within the EU from the Netherlands.
All Pepcore products are intended for laboratory research only. They are not for human or veterinary consumption.
For laboratory research use only – not for human or veterinary use. All Pepcore products are sold strictly as research materials for in vitro use. They are not medicines, supplements, foods or cosmetics. Sold only to adults aged 18 and over.