Oxytocin

Oxytocin (2mg) — Nonapeptide Neurohormone for Social Bonding and Stress-Response Research

Oxytocin (2mg) is supplied in Australia by Omega Peptides Australia from domestic stock, with same-day dispatch on orders placed before 12pm and an independent certificate of analysis for every batch. Commonly written as oxytocin peptide, OT peptide or oxytocin 2mg vial, it is a nine-amino-acid neurohormone studied for its role in social bonding, trust and stress-axis regulation.

Oxytocin is a naturally occurring cyclic nonapeptide with the sequence Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly-NH2, closed by a disulfide bridge between the two cysteine residues and capped with a C-terminal amide. It is produced in the paraventricular and supraoptic nuclei of the hypothalamus and released systemically by the posterior pituitary. Oxytocin holds a notable place in peptide history: it was the first peptide hormone ever chemically synthesised, by Vincent du Vigneaud in 1953, work that earned the 1955 Nobel Prize in Chemistry.

Oxytocin is studied in three main directions: as the reference ligand for social neuroscience research into bonding, trust and empathy; as a modulator of the hypothalamic-pituitary-adrenal axis with anxiolytic effects in preclinical models; and as a smooth-muscle signalling molecule in uterine and mammary tissue. At the receptor level it activates the oxytocin receptor (OXTR), a Gq-coupled GPCR that also cross-reacts with vasopressin V1a receptors due to the close structural similarity between the two hormones.

Omega Peptides Australia supplies Oxytocin as a high-purity (≥99% HPLC) COA-verified lyophilised powder in a sealed 2mg vial. Orders placed before 12pm are dispatched the same day from stock held within Australia, and the batch Certificate of Analysis for every lot is published in our COA library so the purity and identity of the vial you receive can be checked against the batch number on the label.

Key research areas

• Social bonding and pair-bonding behaviour. Oxytocin is the reference compound in pair-bonding research, most famously in prairie vole models where receptor density in reward circuitry predicts monogamous bonding behaviour. It remains the standard tool for studying attachment formation between mates and between parent and offspring.
• Trust, empathy and social cognition. Human and animal studies have examined oxytocin's role in trust, facial-emotion recognition, empathy and in-group social preference, making it a key compound in social-cognition and behavioural neuroscience research.
• HPA-axis and stress-response modulation. Oxytocin has been studied for its ability to dampen hypothalamic-pituitary-adrenal axis activity, reducing cortisol output and blunting the physiological stress response in preclinical models.
• Anxiolytic effects in preclinical models. Research has examined oxytocin's interaction with the amygdala and fear-extinction circuits, with rodent studies reporting reduced anxiety-like behaviour following administration.
• Smooth-muscle signalling. Oxytocin acts directly on uterine myometrial tissue to drive contraction and on myoepithelial cells in the mammary gland to trigger the milk-ejection reflex, making it a standard tool in reproductive and lactation physiology research.
• Comparative studies with PT-141 and the melanocortin system. Oxytocin is frequently studied alongside melanocortin receptor agonists such as PT-141 to compare oxytocinergic and melanocortin pathways in models of social and sexual behaviour.

How Oxytocin works

Oxytocin binds the oxytocin receptor, a Gq/11-coupled G-protein-coupled receptor expressed in the hypothalamus, amygdala, uterus and mammary gland. Receptor activation stimulates phospholipase C, generating inositol trisphosphate and diacylglycerol; inositol trisphosphate releases calcium from intracellular stores, driving smooth-muscle contraction in the uterus and myoepithelial cells, and modulating neuronal excitability in social and limbic circuits in the brain. Because oxytocin and arginine vasopressin differ by only two amino acids, oxytocin also binds vasopressin V1a receptors at higher concentrations, which is a key consideration when isolating oxytocin-specific effects in receptor-binding and knockout models.

In the central nervous system, oxytocin released from hypothalamic neurons acts locally within the brain independently of its peripheral release into the bloodstream via the posterior pituitary, a dual signalling arrangement that is central to why the compound produces both behavioural effects (bonding, anxiety, trust) and peripheral effects (uterine contraction, milk ejection) through the same molecule.

Specifications

Available sizes and pricing

Oxytocin is supplied in a single 2mg vial. Laboratories that need reconstitution supplies can add the Research Starter Kit, which bundles bacteriostatic water, syringes and alcohol swabs in one pack.

• 2mg vial — $79.99 (about $40.00 per mg)

Quality and COA verification

Every batch of Oxytocin is tested independently by Janoshik Analytical before it is released. The HPLC purity assay quantifies the intact cyclic nonapeptide against deamidated or reduced (open-ring) impurities, and mass spectrometry confirms that the measured molecular mass matches the expected value for the disulfide-bonded sequence. A Certificate of Analysis is issued for every lot and published in our COA library, where it can be matched to the batch number on the vial label. The peptide is lyophilised for long-term stability, sealed in a sterile glass vial with a crimped cap, and packed with cushioning for domestic transit so the powder arrives dry and intact.

Frequently bought together

• Bacteriostatic Water (10mL) — $29.99, the recommended diluent for reconstituting lyophilised Oxytocin.
• PT-141 (10mg) — $69.99, the melanocortin agonist used alongside oxytocin in comparative social and sexual behaviour research.

Research guides

• How to store lyophilised peptides
• COA testing explained
• Peptide reconstitution calculator
• Certificates of Analysis library

Frequently asked questions

What is Oxytocin?
Oxytocin is a naturally occurring nine-amino-acid neurohormone produced in the hypothalamus and released by the posterior pituitary. It is studied for its role in social bonding, trust, stress-axis regulation and uterine and mammary smooth-muscle signalling. It is supplied here as a lyophilised, COA-verified powder for in-vitro laboratory research only.

What is Oxytocin also known as?
It is also written as OT, oxytocin peptide or oxytocin 2mg vial, and is informally referred to as the "bonding hormone" or "love hormone" in general literature due to its role in social attachment research.

How does Oxytocin work?
Oxytocin binds the oxytocin receptor, a Gq-coupled receptor that activates phospholipase C and releases intracellular calcium. This drives smooth-muscle contraction in the uterus and mammary gland and modulates neuronal circuits involved in social behaviour, trust and anxiety. It also cross-reacts with vasopressin V1a receptors due to close structural similarity with vasopressin.

What does the research show about Oxytocin?
Preclinical and human studies report that oxytocin promotes pair-bonding and parental attachment, increases trust and social recognition, reduces HPA-axis activity and cortisol output, and produces anxiolytic effects through amygdala-linked circuits. Peripherally, it is well established as the driver of uterine contraction and the milk-ejection reflex. All of this describes laboratory and preclinical research and does not relate to any use outside that setting.

Can I buy Oxytocin at Chemist Warehouse or a pharmacy in Australia?
The research-grade lyophilised Oxytocin supplied here is a laboratory reagent for research use and is a separate product from any pharmacy-dispensed formulation. It is not sold as a medicine or supplement and is not intended as a substitute for any registered pharmaceutical product.

How do you reconstitute Oxytocin?
Use bacteriostatic water. Draw the required volume into a sterile syringe and add it slowly down the inside wall of the vial so the stream does not strike the lyophilised cake directly. Swirl gently until the solution is clear and do not shake, as agitation can degrade the peptide. Refrigerate the reconstituted vial at 2–8°C and use it within 28 days.

How should Oxytocin be stored?
Keep the unopened lyophilised vial at 2–8°C for short-term storage or at −20°C for long-term storage, protected from light and moisture and away from repeated freeze-thaw cycles. After reconstitution, keep the solution at 2–8°C and use it within 28 days.

Where can I buy Oxytocin in Australia?
Omega Peptides Australia holds Oxytocin in domestic stock and dispatches orders placed before 12pm on the same business day with tracked shipping within Australia. Each batch is backed by an independent Certificate of Analysis that you can review in the COA library before ordering.

What does Oxytocin cost in Australia?
Oxytocin is supplied in a 2mg vial at $79.99, about $40.00 per milligram. Bacteriostatic water is sold separately at $29.99 for 10mL or $14.99 for 3mL.

How do I get Oxytocin online in Australia?
Open the Oxytocin product page, select the 2mg vial, add it to the cart and complete checkout. Orders placed before 12pm are dispatched the same business day from our Australian stock, travelling by tracked domestic courier in plain, discreet packaging with a tracking number emailed as soon as the order ships.

Is Oxytocin legal in Australia?
Omega Peptides Australia supplies Oxytocin strictly for lawful in-vitro laboratory research. Purchasers are responsible for ensuring their intended use complies with all applicable laws.

Oxytocin vs PT-141: which is used for what in research?
Oxytocin acts on the oxytocin receptor and is the standard tool for bonding, trust and stress-axis research, while PT-141 is a melanocortin-4 receptor agonist studied for sexual behaviour and libido pathways. The two are frequently studied side by side to separate oxytocinergic and melanocortin contributions to social and sexual behaviour models.

⚠ For in-vitro research and laboratory use only. Not for human or veterinary use.