Oxytocin Acetate

Oxytocin Acetate (also known as α-Hypophamine acetate) is a synthetic acetate salt form of oxytocin, a cyclic nonapeptide hormone composed of nine amino acids. Oxytocin is primarily synthesized in magnocellular neurons of the paraventricular and supraoptic nuclei of the hypothalamus and is released by the posterior pituitary gland. As a medication and hormone, oxytocin is best known for its role in reproductive biology, facilitating uterine contractions during labor, lactation, and prosocial behaviors. The compound is widely studied in endocrinology, neuroscience, and reproductive research for its pleiotropic effects on parturition, lactation, social bonding, stress responses, and neuroprotection.

Oxytocin acetate exerts its effects through multiple interconnected mechanisms. As the primary ligand for the oxytocin receptor (OXTR)—a G protein-coupled receptor expressed in the myometrium, mammary gland, and central nervous system—oxytocin induces uterine contractions by increasing intracellular calcium (Ca²⁺) levels in myometrial cells. The concentration of oxytocin receptors in the myometrium increases significantly during pregnancy, reaching a maximum in early labor at term. Beyond its classical reproductive functions, oxytocin functions as a stress-coping molecule with anti-inflammatory, antioxidant, and protective effects. Oxytocin also acts as a positive allosteric modulator of μ-opioid receptor (MOR) signaling, enhancing opioid receptor activity. Additionally, oxytocin modulates gene expression in myometrial microvascular endothelial cells and plays a role in social bonding, sexual reproduction, and cognitive processes.

• Reproductive Biology: Investigated for inducing uterine contractions, facilitating labor and delivery, and controlling postpartum bleeding or hemorrhage.
• Lactation Research: Studied for its role in milk ejection and lactation through stimulation of mammary gland myoepithelial cells.
• Neuroendocrinology and Social Behavior: Employed to study social bonding, pair bonding, anxiety modulation, and prosocial behaviors.
• Psychiatric and Neurological Research: Investigated for therapeutic potential in autism spectrum disorders, anxiety, depression, and schizophrenia.
• Stress and Inflammation Research: Utilized to evaluate anti-inflammatory, antioxidant, and stress-coping mechanisms.
• Muscle and Satellite Cell Research: Studied for its role in steroid hormone-stimulated satellite cell proliferation and differentiation in skeletal muscle.

CAS Number: 6233-83-6 (acetate salt); 50-56-6 (free base)
PubChem CID: 12004215
Molecular Formula: C₄₃H₆₆N₁₂O₁₂S₂·C₂H₄O₂ (acetate salt); C₄₃H₆₆N₁₂O₁₂S₂ (free base)
Molecular Weight: 1,067.24 g/mol (acetate salt); 1,007.19 g/mol (free base)
Sequence (Three-Letter Code): H-Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly-NH₂ (Disulfide bridge: Cys¹–Cys⁶)
Sequence (One-Letter Code): CYIQNCPLG-NH₂ (Disulfide bridge: Cys¹–Cys⁶)
Purity: ≥ 99%
Form: White to off-white lyophilized powder
Storage: Store lyophilized at ≤ -20°C in a cool, dry place, protected from light and moisture. In lyophilized form, the compound is stable for extended periods; in solution, store at -20°C and use within 1 month to prevent loss of potency. Aliquot to avoid multiple freeze-thaw cycles
Solubility: Soluble in sterile water, DMSO (14 mg/mL), PBS (pH 7.2, 5 mg/mL), and ethanol (5 mg/mL); prepare working solutions per laboratory protocol