Atosiban (Synonyms: RW22164; RWJ22164)

Name: Atosiban
Brand: MedChemExpress
SKU: HY-17572
Rating: 5.0 (7 reviews)

Cat. No.: HY-17572 Purity: 99.44%: Data Sheet
COA

SDS
Handling Instructions
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Atosiban (RW22164; RWJ22164) is a nonapeptide competitive vasopressin/oxytocin receptor antagonist, and is a desamino-oxytocin analogue. Atosiban is the main tocolytic agent and has the potential for spontaneous preterm labor research.

For research use only. We do not sell to patients.

Custom Peptide Synthesis

CAS No. : 90779-69-4

Size	Stock	Quantity
5 mg	In-stock	Estimated Time of Arrival: December 31
10 mg	In-stock	Estimated Time of Arrival: December 31
25 mg	In-stock	Estimated Time of Arrival: December 31
50 mg	In-stock	Estimated Time of Arrival: December 31
100 mg	In-stock	Estimated Time of Arrival: December 31
200 mg	Get quote
500 mg	Get quote

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Customer Review

Based on 7 publication(s) in Google Scholar

Other Forms of Atosiban:

Atosiban acetate In-stock
Atosiban (Standard) Get quote

7 Publications Citing Use of MCE Atosiban

•Front Neurosci. 2021 Sep 10:15:723064. [Abstract]

In Vivo Efficacy Study

Bio/Physico-chemical Assay

: Atosiban purchased from MedChemExpress. Usage Cited in: Neuron. 2026 Mar 26:S0896-6273(26)00120-0.; Representative traces and quantification of oEPSC amplitude with OXTR agonist (TGOT, red) or antagonist (Atosiban, blue). The results showed that during high-frequency stimulation (50 Hz), TGOT increased the amplitude of the first oEPSC, while Atosiban (1 μM) reduced it, indicating that OXTR activation strengthened synaptic transmission.

: Atosiban purchased from MedChemExpress. Usage Cited in: Curr Biol. 2025 Sep 26:S0960-9822(25)01182-0. [Abstract]; Atosiban (50 μM, 500 nL; bilaterally microinjected into the dorsal bed nucleus of the stria terminalis (dBNST)) administration induced anxiety-like behaviors, as evidenced by reduced exploratory activity in both the OF and EPM tests in sham-treated mice.

: Atosiban purchased from MedChemExpress. Usage Cited in: Neurosci Bull. 2025 Aug 6. [Abstract]; The icv injection of an oxytocin antagonist Atosiban (OTA, 5 mg/mL; i.c.v.) prevented mechanical allodynia in female cage-mate, female stranger, and male stranger rats; and the icv injection of oxytocin in male stranger rats induced mechanical allodynia after 30-min social interaction with painful CCI rats.

: Atosiban purchased from MedChemExpress. Usage Cited in: Neurosci Bull. 2025 Aug 6. [Abstract]; Immunofluorescence showing c-Fos-positive cells in the mPFC (as a control group) and ACC (aACC, mACC, and pACC) after icv injection of an oxytocin antagonist (Atosiban (OTA, 5 mg/mL; i.c.v.) ) in females or oxytocin in males after social interaction with painful CCI rats. Left: representative immunofluorescent staining images. Right: data summary. Tissues were collected immediately after 30-min social interaction (n = 6 rats).

: Atosiban purchased from MedChemExpress. Usage Cited in: Front Neurosci. 2021 Sep 10:15:723064. [Abstract]; The time spent in the social interaction zone was measured in the social interaction test. Pretreatment with atosiban (2.5 ng/μL; once daily for 5 days; injected into the medial prefrontal cortex (mPFC)) 30 min before each oxytocin infusion in the mPFC showed a trend of attenuation of the social interaction behavior, which was improved by oxytocin in ketamine-treated mice, although there was no significant difference between groups.

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Biological Activity
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References
Customer Review

Description

In Vitro

Atosiban inhibits the oxytocin-mediated release of IP3 from the myometrial cell membrane. There is reduced release of intracellular, stored calcium from the sacroplasmic reticulum of myometrial cells, and reduced influx of Ca²⁺ from the extracellular space through voltage gated channels. In addition, Atosiban suppresses oxytocin-mediated release of PGE and PGF from the decidua^[1].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

In Vivo

The posterior pituitary hormones, oxytocin and arginine vasopressin, differ in structure by only two amino acids, and Atosiban influences physiological effects of arginine vasopressin on the feto-maternal cardiovascular and renal systems. In late-gestation sheep, the administration of Atosiban for 1 hour fails to induce fetomaternal cardiovascular changes^[1].
Atosiban blocks the activation of oxytocin-receptor-expressing neurons in the parabrachial nucleus of mice^[2].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

Clinical Trial

Molecular Weight

994.19

Formula

C₄₃H₆₇N₁₁O₁₂S₂

CAS No.

90779-69-4

Appearance

Solid

Color

White to off-white

Shipping

Room temperature in continental US; may vary elsewhere.

Storage

Sealed storage, away from moisture

Powder	-80°C	2 years
	-20°C	1 year

*In solvent : -80°C, 6 months; -20°C, 1 month (sealed storage, away from moisture)

Solvent & Solubility

In Vitro:

DMSO : ≥ 200 mg/mL (201.17 mM; Hygroscopic DMSO has a significant impact on the solubility of product, please use newly opened DMSO)

H₂O : 16.67 mg/mL (16.77 mM; Need ultrasonic)

*"≥" means soluble, but saturation unknown.

Preparing
Stock Solutions

Concentration Solvent Mass	1 mg	5 mg	10 mg

1 mM	1.0058 mL	5.0292 mL	10.0584 mL
5 mM	0.2012 mL	1.0058 mL	2.0117 mL
10 mM	0.1006 mL	0.5029 mL	1.0058 mL

View the Complete Stock Solution Preparation Table

* Please refer to the solubility information to select the appropriate solvent. Once prepared, please aliquot and store the solution to prevent product inactivation from repeated freeze-thaw cycles.
Storage method and period of stock solution: -80°C, 6 months; -20°C, 1 month (sealed storage, away from moisture). When stored at -80°C, please use it within 6 months. When stored at -20°C, please use it within 1 month.

* Note: If you choose water as the stock solution, please dilute it to the working solution, then filter and sterilize it with a 0.22 μm filter before use.

Molarity Calculator
Dilution Calculator

Mass (g) = Concentration (mol/L) × Volume (L) × Molecular Weight (g/mol)

Concentration _(start) × Volume _(start) = Concentration _(final) × Volume _(final)

This equation is commonly abbreviated as: C₁V₁ = C₂V₂

Concentration _(start)

Volume _(start)

Concentration _(final)

Volume _(final)

In Vivo:

Select the appropriate dissolution method based on your experimental animal and administration route.

For the following dissolution methods, please ensure to first prepare a clear stock solution using an In Vitro approach and then sequentially add co-solvents:
To ensure reliable experimental results, the clarified stock solution can be appropriately stored based on storage conditions. As for the working solution for in vivo experiments, it is recommended to prepare freshly and use it on the same day.
The percentages shown for the solvents indicate their volumetric ratio in the final prepared solution. If precipitation or phase separation occurs during preparation, heat and/or sonication can be used to aid dissolution.

Protocol 1

Add each solvent one by one: 10% DMSO 40% PEG300 5% Tween-80 45% Saline
Solubility: ≥ 1.67 mg/mL (1.68 mM); Clear solution

This protocol yields a clear solution of ≥ 1.67 mg/mL (saturation unknown).
Taking 1 mL working solution as an example, add 100 μL DMSO stock solution (16.7 mg/mL) to 400 μL PEG300, and mix evenly; then add 50 μL Tween-80 and mix evenly; then add 450 μL Saline to adjust the volume to 1 mL.
Preparation of Saline: Dissolve 0.9 g sodium chloride in ddH₂O and dilute to 100 mL to obtain a clear Saline solution.
Protocol 2

Add each solvent one by one: 10% DMSO 90% (20% SBE-β-CD in Saline)
Solubility: ≥ 1.67 mg/mL (1.68 mM); Clear solution

This protocol yields a clear solution of ≥ 1.67 mg/mL (saturation unknown).
Taking 1 mL working solution as an example, add 100 μL DMSO stock solution (16.7 mg/mL) to 900 μL 20% SBE-β-CD in Saline, and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C, storage for one week): 2 g SBE-β-CD powder is dissolved in 10 mL Saline, completely dissolve until clear.
Protocol 3

Add each solvent one by one: 10% DMSO 90% Corn Oil
Solubility: ≥ 1.67 mg/mL (1.68 mM); Clear solution

This protocol yields a clear solution of ≥ 1.67 mg/mL (saturation unknown). If the continuous dosing period exceeds half a month, please choose this protocol carefully.
Taking 1 mL working solution as an example, add 100 μL DMSO stock solution (16.7 mg/mL) to 900 μL Corn oil, and mix evenly.

In Vivo Dissolution Calculator

Please enter the basic information of animal experiments:

Dosage

mg/kg

Animal weight
(per animal)

Dosing volume
(per animal)

μL

Number of animals

Recommended: Prepare an additional quantity of animals to account for potential losses during experiments.

Calculation results:

Working solution concentration: mg/mL

This product has good water solubility, please refer to the measured solubility data in water/PBS/Saline for details.

The concentration of the stock solution you require exceeds the measured solubility. The following solution is for reference only.If necessary, please contact MedChemExpress (MCE).

Purity & Documentation

Purity: 99.44%

Select Batch:

Data Sheet (278 KB) SDS (479 KB)

COA (255 KB) RP-HPLC (109 KB) MS (179 KB) Elemental Analysis Report (114 KB)

Handling Instructions (2659 KB)

References

[1]. Sanu O, et al. Critical appraisal and clinical utility of atosiban in the management of preterm labor. Ther Clin Risk Manag. 2010 Apr 26;6:191-9. [Content Brief]

[2]. Philip J Ryan, et al. Oxytocin-receptor-expressing Neurons in the Parabrachial Nucleus Regulate Fluid Intake. Nat Neurosci. 2017 Dec;20(12):1722-1733. [Content Brief]

Complete Stock Solution Preparation Table

Optional Solvent	Concentration Solvent Mass	1 mg	5 mg	10 mg	25 mg

H₂O / DMSO	1 mM	1.0058 mL	5.0292 mL	10.0584 mL	25.1461 mL
	5 mM	0.2012 mL	1.0058 mL	2.0117 mL	5.0292 mL
	10 mM	0.1006 mL	0.5029 mL	1.0058 mL	2.5146 mL
	15 mM	0.0671 mL	0.3353 mL	0.6706 mL	1.6764 mL
DMSO	20 mM	0.0503 mL	0.2515 mL	0.5029 mL	1.2573 mL
	25 mM	0.0402 mL	0.2012 mL	0.4023 mL	1.0058 mL
	30 mM	0.0335 mL	0.1676 mL	0.3353 mL	0.8382 mL
	40 mM	0.0251 mL	0.1257 mL	0.2515 mL	0.6287 mL
	50 mM	0.0201 mL	0.1006 mL	0.2012 mL	0.5029 mL
	60 mM	0.0168 mL	0.0838 mL	0.1676 mL	0.4191 mL
	80 mM	0.0126 mL	0.0629 mL	0.1257 mL	0.3143 mL
	100 mM	0.0101 mL	0.0503 mL	0.1006 mL	0.2515 mL

* Note: If you choose water as the stock solution, please dilute it to the working solution, then filter and sterilize it with a 0.22 μm filter before use.

Atosiban Related Classifications

Help & FAQs

Do most proteins show cross-species activity?
Species cross-reactivity must be investigated individually for each product. Many human cytokines will produce a nice response in mouse cell lines, and many mouse proteins will show activity on human cells. Other proteins may have a lower specific activity when used in the opposite species.

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Atosiban (Synonyms: RW22164; RWJ22164)

Customer Review

Other Forms of Atosiban:

Atosiban Related Antibodies

7 Publications Citing Use of MCE Atosiban

Featured Recommendations

•Related Screening Libraries:

•Related Small Molecules:

•Related Proteins:

View All Vasopressin Receptor Isoform Specific Products:

Biological Activity

Purity & Documentation

References

Customer Review

Atosiban Related Antibodies

Molarity Calculator

Dilution Calculator

Complete Stock Solution Preparation Table

Atosiban Related Classifications

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Your Recently Viewed Products:

Customer Review

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