What is Oxytocin acetate?

Oxytocin acetate is the acetate salt form of oxytocin, a nine-amino-acid cyclic nonapeptide (Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly-NH2, with a disulfide bridge between the two cysteine residues) and the endogenous ligand for the oxytocin receptor. Synonyms in the research literature include oxytocin diacetate and, less precisely, simply oxytocin; the acetate counter-ion is used to improve handling and solubility of the peptide in laboratory formulations. The free peptide has a molecular formula of C43H66N12O12S2 and a molecular weight of approximately 1007.19 g/mol; the acetate salt is supplied as a lyophilised solid for research use. Identifiers commonly attached to the material include the CAS number 50-56-6 for the free peptide and 6233-83-6 for the diacetate.

The work described on this page centres on the oxytocin receptor (OXTR), a class A G-protein-coupled receptor that signals principally through Gq/11 and the phospholipase C–inositol trisphosphate pathway, and on the closely related vasopressin receptors with which oxytocin and its analogues cross-react.

Research Studies

Oxytocin acetate and uterine involution in dairy cows

A randomised study in cattle compared three substances with ecbolic activity — oxytocin, prostaglandin F2α and scopolamine — for their effect on uterine involution and the resumption of ovarian activity after calving [3]. Eighty bovine were randomly divided into four groups of twenty. The oxytocin group received 50 IU per head of oxytocin acetate within 24 hours of calving; a control group received 5 mL per head of saline; a prostaglandin group received 150 µg per head of d-cloprostenol; and a scopolamine group received 40 mg of scopolamine butylbromide [3]. Blood samples were collected to evaluate hydroxyproline, and the study compared the three treatments against saline for the involution process and ovarian resumption [3]. This is an animal study; findings in dairy cows are not transferable to human physiology without further work.

Oxytocin acetate and endogenous oxytocin release in paediatric pituitary disease

An open-label, interventional pilot trial is recruiting ten youth with arginine-vasopressin deficiency (AVP-D) and ten with pituitary disease (PD), matched for age, sex and BMI, from paediatric endocrinology and neuroendocrinology clinics and from the community [1]. The study tests the hypothesis that oral estrogen/progestin will stimulate endogenous oxytocin release in control subjects [1]. Eligible participants receive two tablets in a single administration containing a total of 1 mg of norethindrone acetate and 70 µg of ethinyl estradiol; blood and saliva are sampled at baseline and approximately 24 hours after study drug administration, alongside neuropsychological assessment of anxiety, mood and emotion regulation [1]. The compound under study here is the estrogen/progestin challenge; oxytocin is the measured outcome, not the administered agent.

Oxytocin and oxytocin response in adults with pituitary disease

A separate open-label pilot study characterises the oxytocin response to a single dose of oral estrogen-progestin in patients with arginine-vasopressin deficiency compared with healthy controls, and examines the association between oxytocin levels and measures of psychopathology (anxiety and depression) and quality of life across groups [2]. The stated hypotheses are that salivary and blood oxytocin response to estrogen-progestin will be lower in arginine-vasopressin deficiency than in healthy controls, and that lower salivary and blood oxytocin levels will be associated with more severe symptoms of anxiety, depression and social-emotional difficulties, as well as lower quality of life [2]. As with the paediatric protocol, oxytocin is the analyte; the intervention is a combined oral estrogen-progestin tablet.

Oxytocin receptor antagonism and preterm labour: retosiban versus atosiban

A randomised, double-blind, double-dummy study compared retosiban with atosiban in women in spontaneous preterm labour [7]. The primary objective was to demonstrate the superiority of retosiban over atosiban in prolonging pregnancy, on the hypothesis that prolonging time to delivery in the absence of harm may benefit the newborn, particularly in women presenting at early gestational ages [7]. Atosiban is described in the protocol as a mixed oxytocin-vasopressin antagonist indicated for short-term use to delay imminent preterm birth in women between 24^0/7 and 33^6/7 weeks' gestation in preterm labour [7]. This study concerns receptor-level antagonism of the oxytocin/vasopressin axis rather than administration of oxytocin acetate itself.

Oxytocin and haemodynamic measurement during caesarean delivery

A study protocol describes measurement of cardiac output in healthy parturients undergoing caesarean delivery under spinal anaesthesia [4]. The protocol does not specify oxytocin acetate as an intervention in the excerpt available; it is included here because oxytocin is routinely relevant to the peripartum setting in which such haemodynamic work is conducted, and because the same research group context appears in related obstetric protocols [5][6]. No finding on oxytocin acetate can be attributed to this record.

Oxytocin and fluid assessment in preeclampsia

A protocol describes ultrasonographic fluid assessment in parturients with preeclampsia undergoing caesarean section [5]. Preeclampsia is described as a multifocal syndrome reported in 2–8% of pregnancies, diagnosed in the second half of pregnancy by two separate measurements of systolic blood pressure ≥140 mmHg and/or diastolic blood pressure ≥90 mmHg in the same arm, together with proteinuria >300 mg in a 24-hour urine collection; the risk of serious complications such as pulmonary oedema, cerebrovascular accidents, coagulopathy and haemorrhage is reported as 10- to 30-fold higher among parturients with severe preeclampsia [5]. Severe preeclampsia is defined by one or more features including severe hypertension (systolic arterial pressure 160 mmHg and/or diastolic arterial pressure 110 mmHg on more than one occasion) [5]. This record does not report an oxytocin acetate finding.

Oxytocin and colloid versus crystalloid comparison in preeclampsia

A further protocol compares a combination of colloids and crystalloids with crystalloids alone in women with preeclampsia undergoing elective caesarean delivery under spinal anaesthesia [6]. As with the preceding obstetric records, the intervention is a fluid strategy, not oxytocin acetate, and no oxytocin finding is reported in the available excerpt.

Oxytocin agonist combined with rTMS in a mouse model of postpartum depression

A study in mice examined the combination of repetitive transcranial magnetic stimulation (rTMS) and an oxytocin agonist and reported attenuation of depression-like behaviour after postpartum depression in that model [8]. The paper situates postpartum depression within the DSM-5 category of major depressive disorder with peripartum onset, generally arising within the first trimester following delivery, and describes the condition as an acute psychiatric state characterised by feelings of worthlessness [8]. This is an animal study; the findings are specific to the mouse model used and do not establish effects in humans.

Comparison of study contexts

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This material is sold for laboratory research only, and we do not provide dosing or medical guidance. Nothing on this page is a recommendation for human use. Anyone considering a compound for themselves should speak to a licensed clinician.

Sources

• [1] Identifying Oxytocin Deficiency in Pediatric Patients With Pituitary Disease — https://clinicaltrials.gov/study/NCT07568509
• [2] Identifying Oxytocin Deficiency in Adults With Pituitary Disease — https://clinicaltrials.gov/study/NCT06460948
• [3] Oxytocin, prostaglandin F2α, and scopolamine for uterine involution of dairy cows — https://europepmc.org/article/PMC/PMC11096567
• [4] Changes in Cardiac Output During Cesarean Delivery Under Spinal Anesthesia — https://clinicaltrials.gov/study/NCT05269537
• [5] Ultrasonography for Fluid Assessment in Parturients With Preeclampsia Undergoing Cesarean Section — https://clinicaltrials.gov/study/NCT04370847
• [6] Combined Colloids And Crystalloids Versus Crystalloids in Women With Preeclampsia Undergoing Cesarean Delivery — https://clinicaltrials.gov/study/NCT03252496
• [7] A Randomized Study Comparing the Efficacy and Safety of Retosiban Versus Atosiban for Women in Spontaneous Preterm Labour — https://clinicaltrials.gov/study/NCT02292771
• [8] Combination of rTMS and oxytocin agonist attenuate depression-like behavior after postpartum depression in mice — https://pubmed.ncbi.nlm.nih.gov/39832612/