Oxytocin

Oxytocin Peptide – OXTR Signaling, Neuroendocrine & Reproductive Research

Cyclic Nonapeptide Hormone for Oxytocin Receptor Biology, Uterine Contractility, Lactation, Social Neuroscience & Cellular Signaling Research

Oxytocin is an endogenous cyclic nonapeptide hormone and neuropeptide involved in reproductive physiology, lactation, neuroendocrine communication and the regulation of selected social and emotional processes.

Produced primarily by neurons in the hypothalamus, oxytocin is transported to the posterior pituitary for release into the bloodstream. Oxytocin is also released within the central nervous system, where it acts as a neuromodulatory signaling molecule.

Its principal molecular target is the oxytocin receptor (OXTR), a G protein-coupled receptor expressed in multiple tissues.

Oxytocin research encompasses several interconnected fields:

• Oxytocin receptor (OXTR) pharmacology

• Hypothalamic and posterior pituitary physiology

• Uterine smooth muscle contractility

• Parturition and reproductive endocrinology

• Mammary myoepithelial cell signaling

• Milk ejection physiology

• Social cognition and behavioral neuroscience

• Maternal and infant-associated behavior

• Stress-associated neuroendocrine responses

• Neuronal signaling and synaptic plasticity

• GPCR signaling and intracellular calcium regulation

• Peptide stability and analytical characterization

Unlike many experimental research peptides, oxytocin is also an established pharmaceutical active ingredient used in licensed medicines for specific obstetric indications.

However, a research-grade oxytocin preparation is not equivalent to an approved pharmaceutical product.

ICAME Pharmacy Oxytocin is intended strictly for laboratory research and development purposes. Not for human or veterinary use.

What Is Oxytocin?

Oxytocin is a naturally occurring peptide hormone consisting of nine amino acid residues.

It belongs to the neurohypophyseal hormone family, alongside the structurally related hormone vasopressin.

The hormone is synthesized mainly in magnocellular neurons of the hypothalamic paraventricular and supraoptic nuclei.

These neurons produce oxytocin as part of a larger precursor protein.

Following processing, oxytocin is transported along neuronal axons and stored in neurosecretory terminals within the posterior pituitary.

Physiological stimulation can trigger its release into systemic circulation.

Oxytocin is particularly important in two well-established peripheral functions:

Uterine contractions during labor

Milk ejection during lactation

Within the brain, oxytocin participates in more complex signaling networks associated with reproductive behavior, social processing and stress responses.

The effects of oxytocin vary according to receptor expression, tissue type, physiological conditions and experimental context.

Oxytocin Molecular Structure

Oxytocin is a cyclic nonapeptide containing nine amino acids.

Its structure includes a disulfide bond between two cysteine residues.

This bond creates a six-residue ring with a short peptide tail.

Molecular Characteristics

These characteristics refer to the oxytocin peptide itself.

Different pharmaceutical or research formulations may contain additional excipients, counterions or other components.

Oxytocin Amino Acid Sequence

The amino acid sequence of oxytocin is:

Cys–Tyr–Ile–Gln–Asn–Cys–Pro–Leu–Gly–NH₂

The corresponding one-letter sequence is:

CYIQNCPLG-NH₂

Amino Acid Composition

The cysteine residues at positions 1 and 6 form an intramolecular disulfide bridge.

This structural feature is important for the peptide's conformation and receptor interactions.

The C-terminal glycine residue is amidated.

Terminal chemistry and disulfide integrity are important considerations when identifying and characterizing synthetic oxytocin.

Why Is Oxytocin a Cyclic Peptide?

Oxytocin is classified as a cyclic peptide because part of its structure forms a closed ring.

The ring is created by a covalent disulfide bond.

Unlike peptides cyclized through an amide linkage, oxytocin contains a sulfur–sulfur bridge.

Structural Research Areas

Disulfide bond formation

Peptide folding

Receptor recognition

Molecular conformation

Structure–activity relationships

Oxidation and reduction chemistry

Peptide stability

Disruption of the disulfide bond can alter the peptide's molecular structure and biological activity.

For this reason, analytical characterization should verify the expected intact molecular species.

Discovery and Scientific History of Oxytocin

Oxytocin has an important place in the history of peptide chemistry.

In the early twentieth century, researchers identified biological activity associated with extracts of the posterior pituitary.

Sir Henry Dale described uterine-contracting activity in 1906.

Subsequent research established oxytocin as a distinct peptide hormone.

In the 1950s, Vincent du Vigneaud and colleagues determined its structure and achieved its chemical synthesis.

This work represented a major milestone in peptide chemistry.

Oxytocin became one of the first peptide hormones to be synthesized chemically.

The discovery helped establish foundational methods for peptide structure determination and synthesis.

Today, oxytocin remains a widely studied molecule in endocrinology, neuroscience and pharmacology.

How Does Oxytocin Work?

Oxytocin produces many of its effects by binding to the oxytocin receptor.

OXTR belongs to the class A family of G protein-coupled receptors.

Receptor activation can trigger intracellular signaling pathways.

A major pathway involves the Gq/11 family of G proteins.

Simplified Oxytocin Signaling Pathway

Oxytocin

↓

OXTR Binding

↓

Gq/11 Protein Activation

↓

Phospholipase C-β Activation

↓

PIP₂ Hydrolysis

↓

IP₃ + DAG Formation

↓

Intracellular Calcium Signaling + Protein Kinase C Activation

↓

Tissue-Specific Cellular Responses

In smooth muscle cells, increased intracellular calcium contributes to contraction.

In neurons, OXTR signaling may influence excitability, synaptic transmission and intracellular signaling networks.

OXTR can also engage other signaling mechanisms, including Gi-associated pathways, depending on cellular context.

Therefore, the biological activity of oxytocin should not be reduced to a single universal signaling response.

Oxytocin and the OXTR Receptor

The oxytocin receptor is a seven-transmembrane G protein-coupled receptor.

It is encoded by the OXTR gene.

OXTR expression has been identified in reproductive tissues and multiple regions of the nervous system.

Principal Research Areas

Receptor binding

G protein coupling

Intracellular calcium signaling

Phospholipase C activation

Protein kinase C signaling

Receptor desensitization

Receptor internalization

Cellular signal integration

Receptor density and signaling efficiency can vary between tissues and physiological states.

These differences contribute to the diversity of oxytocin responses.

Oxytocin and Gq/11 Signaling

Gq/11 proteins are important mediators of oxytocin receptor activity.

Following receptor activation, Gq/11 stimulates phospholipase C.

Phospholipase C cleaves the membrane phospholipid PIP₂ into:

Inositol 1,4,5-trisphosphate (IP₃)

Diacylglycerol (DAG)

IP₃ promotes calcium release from intracellular stores.

DAG participates in protein kinase C activation.

Together, these signals regulate multiple cellular functions.

This mechanism is particularly relevant to smooth muscle contraction and neuronal signaling.

Oxytocin and Intracellular Calcium

Calcium ions are important intracellular signaling molecules.

Oxytocin receptor activation can increase intracellular calcium through several mechanisms.

These include calcium release from intracellular stores and changes in calcium entry across cellular membranes.

Calcium-Associated Research

Smooth muscle contraction

Cellular excitability

Neurotransmitter release

Protein kinase activity

Signal transduction

Gene regulation

The magnitude and duration of calcium responses depend on cell type and experimental conditions.

Oxytocin and Hypothalamic Research

The hypothalamus is a major site of oxytocin synthesis.

Two particularly important hypothalamic regions are:

Paraventricular Nucleus (PVN)

Supraoptic Nucleus (SON)

Oxytocin-producing neurons participate in neuroendocrine signaling.

Some neurons project to the posterior pituitary.

Others participate in central nervous system circuits.

Hypothalamic Research Areas

Neuropeptide synthesis

Neuronal activity

Hormone release

Stress-associated signaling

Reproductive physiology

Social behavior

Neuroendocrine feedback

The relationship between central and peripheral oxytocin activity is complex.

Peripheral oxytocin measurements do not necessarily provide a reliable representation of central nervous system signaling.

Oxytocin and Posterior Pituitary Physiology

The posterior pituitary stores and releases oxytocin produced in the hypothalamus.

Oxytocin is transported along axons within the hypothalamic–neurohypophyseal system.

Physiological stimulation can trigger release into the circulation.

Research Topics

Neurosecretory vesicles

Axonal transport

Stimulus-dependent hormone release

Neuroendocrine feedback

Peripheral hormone signaling

Hypothalamic–pituitary physiology

The posterior pituitary is primarily a release site rather than the principal site of oxytocin synthesis.

Oxytocin and Uterine Contraction Research

One of the most established biological actions of oxytocin is its ability to stimulate uterine smooth muscle contraction.

Oxytocin receptors are expressed in the myometrium.

Receptor expression and uterine responsiveness change during pregnancy and around labor.

Simplified Uterine Signaling

Oxytocin

↓

Myometrial OXTR Activation

↓

PLC / IP₃ Signaling

↓

Increased Intracellular Calcium

↓

Activation of Contractile Machinery

↓

Uterine Smooth Muscle Contraction

This pathway is central to the physiological and pharmaceutical actions of oxytocin.

Research Areas

Myometrial receptor expression

Calcium signaling

Smooth muscle contractility

Labor-associated physiology

Receptor regulation

Hormonal signaling

Uterine tissue pharmacology

Unlike speculative research applications, oxytocin's uterotonic effects are clinically established.

However, these effects also create significant safety risks when oxytocin is used inappropriately.

Oxytocin and Labor Physiology

Labor involves coordinated hormonal, mechanical and neurological processes.

Oxytocin participates in uterine contractions and feedback mechanisms associated with childbirth.

Cervical stretching and other physiological stimuli can influence oxytocin release.

Positive Feedback

A simplified physiological model is:

Cervical Stretch

↓

Neural Signaling to the Hypothalamus

↓

Oxytocin Release

↓

Uterine Contraction

↓

Additional Cervical Stretch

This feedback process contributes to labor physiology.

However, childbirth is regulated by many interacting pathways, including prostaglandins, inflammatory mediators and mechanical factors.

Oxytocin is not the sole regulator of labor.

Oxytocin and Postpartum Hemorrhage Research

Postpartum hemorrhage is excessive bleeding following childbirth.

Uterine atony, or insufficient uterine contraction, is an important cause.

Oxytocin stimulates uterine contraction and is a well-established uterotonic medicine.

Licensed oxytocin preparations are used in obstetric care under professional supervision.

The World Health Organization recommends quality-assured oxytocin as an important option for postpartum hemorrhage prevention.

Research Topics

Uterine atony

Myometrial contractility

Uterotonic pharmacology

Postpartum physiology

Receptor responsiveness

Pharmaceutical stability

Maternal safety

Clinical monitoring

Important Distinction

The clinical effectiveness of licensed oxytocin medicines does not establish that research-grade oxytocin is suitable for medical administration.

Research products are not substitutes for regulated obstetric medicines.

Oxytocin and Lactation Research

Oxytocin plays a central role in the milk ejection reflex.

Milk production and milk ejection are different physiological processes.

Prolactin is important for milk synthesis.

Oxytocin is important for milk ejection.

Oxytocin acts on myoepithelial cells surrounding mammary alveoli.

Contraction of these cells helps move milk into the ductal system.

Simplified Milk Ejection Pathway

Nipple Stimulation

↓

Neural Signaling

↓

Hypothalamic Activation

↓

Oxytocin Release

↓

Mammary Myoepithelial Cell Contraction

↓

Milk Ejection

Lactation Research Areas

Myoepithelial contractility

Neuroendocrine reflexes

Hormone release

Mammary gland physiology

Oxytocin receptor signaling

Maternal physiology

Oxytocin's role in milk ejection is well established, but it should not be confused with the primary hormonal regulation of milk production.

Oxytocin and Social Behavior Research

Oxytocin has attracted substantial interest in behavioral neuroscience.

It has sometimes been described informally as the “love hormone” or “bonding hormone.”

These expressions are oversimplified.

Oxytocin signaling is involved in complex neural systems that process social information.

Its effects depend on context, individual characteristics and experimental conditions.

Research Areas

Social recognition

Social reward processing

Attachment-associated behavior

Social memory

Emotional processing

Interpersonal responses

Neural network activity

Human studies have produced mixed findings.

Oxytocin does not reliably increase trust, empathy or prosocial behavior in every setting.

Oxytocin and Social Cognition

Social cognition refers to processes involved in interpreting and responding to social information.

Researchers have investigated oxytocin in studies involving:

Facial emotion recognition

Eye gaze

Social attention

Social memory

Interpersonal decision-making

Social reward processing

Neural responses to social stimuli

Some controlled studies report measurable effects.

Others find small, inconsistent or context-dependent responses.

Therefore, oxytocin should not be described as a proven universal enhancer of social cognition.

Oxytocin and Trust Research

Early human studies generated interest in oxytocin's possible influence on interpersonal trust.

However, subsequent research revealed considerable complexity.

Responses may depend on:

Social context

Experimental task

Individual differences

Prior experiences

Sex-related variables

Clinical characteristics

Measurement methods

Oxytocin may alter social information processing without necessarily producing uniformly positive social behavior.

Claims that oxytocin reliably makes people more trusting are scientifically oversimplified.

Oxytocin and Attachment Research

Oxytocin is involved in biological systems relevant to maternal behavior and social attachment.

Animal research has provided important evidence connecting oxytocin signaling with reproductive and affiliative behaviors.

Human research has examined associations between oxytocin-related biology and attachment processes.

However, attachment is influenced by many interacting factors.

Oxytocin is not a single chemical explanation for love, bonding or relationship quality.

Oxytocin and Maternal Behavior

Oxytocin participates in physiological and behavioral processes associated with reproduction.

Animal studies have examined its influence on maternal care and offspring-directed behavior.

Human research has investigated oxytocin-associated neural responses and maternal–infant interactions.

Research Topics

Maternal neural signaling

Reproductive behavior

Infant-associated sensory processing

Neuroendocrine responses

Attachment-related pathways

Stress regulation

However, oxytocin levels do not provide a simple or reliable measure of parental attachment quality.

Oxytocin and Stress Research

Oxytocin has been investigated in stress-related neuroendocrine pathways.

The hypothalamic–pituitary–adrenal (HPA) axis is a major component of the physiological stress response.

Some experimental studies suggest that oxytocin signaling can influence stress-associated responses.

Potential research areas include:

HPA-axis signaling

Cortisol-associated responses

Autonomic activity

Stress-related neural circuits

Social buffering

Emotional regulation

However, results differ across experimental conditions.

Oxytocin is not an established general treatment for stress or anxiety.

Oxytocin and Anxiety Research

Oxytocin has been investigated in animal models and human experiments involving anxiety-associated processes.

Some studies report changes in neural activity or behavioral responses.

Others find inconsistent or null effects.

The influence of oxytocin may depend on individual characteristics and environmental context.

It has not been established as a broadly effective anxiolytic medicine.

Oxytocin and the Amygdala

The amygdala participates in emotional and social information processing.

Human neuroimaging studies have examined whether oxytocin influences amygdala responses.

Reported findings vary according to experimental design and participant characteristics.

Research Topics

Emotional stimulus processing

Social salience

Threat-associated neural responses

Functional connectivity

Amygdala activity

Context-dependent neural modulation

Oxytocin's effects on the amygdala should not be described as uniformly suppressive or beneficial.

Oxytocin and Social Reward Processing

Social reward processing involves neural responses to positive social experiences.

Research has investigated oxytocin-associated activity in brain regions including:

Striatum

Amygdala

Prefrontal cortex

Anterior cingulate cortex

Insula

Other social-processing networks

A systematic review of intranasal oxytocin studies reported some effects on social reward consumption.

However, findings varied across tasks and participants.

These results do not establish oxytocin as a treatment for social difficulties.

Oxytocin and Intranasal Research

Intranasal oxytocin has been widely investigated in human behavioral neuroscience.

Researchers have explored whether intranasal administration can influence central nervous system signaling.

Major Research Questions

Does oxytocin reach relevant brain regions?

How does peripheral exposure relate to central activity?

Which neural circuits are affected?

How reproducible are behavioral findings?

Do responses differ between individuals?

Can experimental effects translate into clinical benefits?

Evidence suggests that intranasal administration can produce measurable central effects in some circumstances.

However, delivery mechanisms, reproducibility and clinical significance remain active research questions.

The presence of published intranasal studies does not make research-grade oxytocin nasal preparations safe or authorized for self-administration.

Oxytocin and Autism Spectrum Research

Oxytocin has been investigated in studies involving social communication and autism spectrum disorder.

The rationale involves oxytocin's role in social information processing.

Some early studies reported promising outcomes.

However, larger and more rigorous research has produced mixed or negative findings.

Oxytocin is not established as an effective general treatment for autism spectrum disorder.

Research continues into whether particular subgroups, outcomes or experimental approaches may be relevant.

Oxytocin and Psychiatric Research

Oxytocin has been investigated in several psychiatric research contexts.

These include:

Social anxiety

Autism-related social processing

Schizophrenia-associated social cognition

Stress-related conditions

Social reward processing

Emotional recognition

However, evidence remains insufficient to establish oxytocin as a broadly effective psychiatric treatment.

Results from small experimental studies should not be presented as proof of clinical efficacy.

Oxytocin and Neuronal Plasticity

Neuronal plasticity refers to changes in neural structure and function.

Oxytocin receptor signaling can influence neuronal activity and synaptic processes.

Preclinical studies have investigated:

Synaptic transmission

Neuronal excitability

Circuit modulation

Calcium-dependent signaling

Neurite-associated processes

Activity-dependent plasticity

These findings contribute to understanding the central oxytocin system.

However, they do not establish that oxytocin improves memory, intelligence or general cognitive performance in humans.

Oxytocin and Memory Research

Oxytocin has been investigated in studies involving social memory and recognition.

Animal research provides evidence that oxytocin signaling participates in certain forms of social recognition.

Human research has explored its influence on processing and remembering social information.

Effects may vary by task and context.

Oxytocin is not an established general memory-enhancing treatment.

Oxytocin and Sexual Behavior Research

Oxytocin participates in neuroendocrine systems associated with reproductive and sexual physiology.

Research has examined oxytocin-related signaling during sexual responses.

Potential research topics include:

Reproductive neuroendocrinology

Autonomic signaling

Social and emotional processing

Sexual-response pathways

Hormone release

Central nervous system activity

However, oxytocin is not an established treatment for sexual dysfunction or a clinically proven libido enhancer.

Oxytocin and Metabolic Research

Oxytocin signaling has also been investigated in experimental metabolic research.

Animal studies have examined its potential roles in energy balance and feeding-related pathways.

Research topics include:

Food intake

Energy homeostasis

Hypothalamic signaling

Metabolic regulation

Autonomic responses

Receptor-mediated physiological effects

However, oxytocin has not been established as a safe or effective weight-loss medicine.

Metabolic effects observed in animals do not necessarily translate into meaningful human clinical outcomes.

Oxytocin vs. Vasopressin

Oxytocin and vasopressin are closely related neurohypophyseal peptide hormones.

Both contain nine amino acid residues and an intramolecular disulfide bond.

However, they differ in amino acid sequence and principal physiological roles.

Oxytocin and vasopressin receptor systems are structurally related.

At certain concentrations, receptor cross-reactivity can occur.

This is an important consideration in pharmacological research.

Oxytocin vs. Carbetocin

Carbetocin is a synthetic oxytocin analogue.

It was developed as a longer-acting uterotonic compound.

Both molecules interact with oxytocin receptor-associated systems.

However, they differ in chemical structure and pharmacokinetic characteristics.

Approved carbetocin products and approved oxytocin products have distinct labeling and clinical requirements.

Oxytocin vs. KPV

Oxytocin and KPV are structurally and functionally distinct peptides.

Oxytocin is a cyclic nonapeptide hormone.

KPV is a linear tripeptide derived from the C-terminal region of α-MSH.

The two peptides should not be considered interchangeable.

Oxytocin Receptor Desensitization Research

Prolonged receptor stimulation can alter GPCR responsiveness.

Oxytocin receptor desensitization is an important area of receptor pharmacology.

Research may examine:

Receptor phosphorylation

β-Arrestin-associated mechanisms

Receptor internalization

Changes in downstream signaling

Receptor recycling

Altered tissue responsiveness

These processes are relevant to understanding how cells respond to sustained receptor activation.

They also illustrate why oxytocin responses may differ with exposure conditions.

Oxytocin Clinical Applications vs. Research Applications

Oxytocin is unusual among research peptides because it has established medical uses.

It is therefore essential to distinguish between pharmaceutical oxytocin and research-grade peptide material.

Licensed Pharmaceutical Oxytocin

Approved products are used for specific obstetric indications according to local labeling and clinical protocols.

These may include medically supervised induction or augmentation of labor and prevention or management of postpartum hemorrhage.

Such products must meet applicable pharmaceutical quality, manufacturing and regulatory requirements.

Research-Grade Oxytocin

Research-grade oxytocin is intended for laboratory investigation.

It is not automatically manufactured, tested or authorized to the same standards as an approved medicine.

It should not be used for human or veterinary administration.

Key Distinction

The fact that oxytocin is an approved drug substance does not mean every product labeled “oxytocin” is an approved medicine.

Product-specific authorization and quality requirements remain essential.

Oxytocin Safety Considerations

Oxytocin has clinically significant physiological effects.

Its safety depends on the formulation, indication, patient characteristics and medical supervision.

Excessive Uterine Stimulation

Excessive uterine contractions can create serious maternal and fetal risks.

Cardiovascular Effects

Oxytocin can influence vascular and cardiovascular physiology.

Rapid systemic exposure may be associated with hypotension and other hemodynamic changes.

Water Intoxication and Hyponatremia

Oxytocin can produce antidiuretic effects under certain conditions.

Excessive exposure, particularly in relevant fluid-management contexts, can contribute to water intoxication and low serum sodium.

Receptor Cross-Reactivity

Oxytocin and vasopressin receptor systems are related.

Off-target receptor interactions may be relevant under certain experimental conditions.

Formulation Quality

Peptide degradation, impurities and inadequate storage can affect product quality.

Unregulated Human Use

Research-grade products may lack the validated manufacturing, sterility and quality requirements of approved pharmaceutical products.

Central Nervous System Effects

Behavioral and neuroendocrine effects can be context-dependent and are not fully predictable.

Research-grade oxytocin must not be used as a substitute for prescribed obstetric medication or as an unapproved behavioral or wellness treatment.

Oxytocin Peptide Stability

Oxytocin stability is an important consideration in both research and pharmaceutical science.

Its structure includes a disulfide bond and multiple peptide bonds.

Potential degradation processes include:

Oxidation-related changes

Disulfide-associated reactions

Peptide bond degradation

Deamidation-related pathways

Aggregation or adsorption

Temperature-dependent degradation

pH-dependent chemical changes

Actual stability depends on the formulation and environmental conditions.

Storage requirements should be based on validated, product-specific stability data.

No universal storage or reconstitution procedure should be assumed for all oxytocin products.

Oxytocin and Analytical Characterization

Appropriate analytical testing is essential for peptide research.

High-Performance Liquid Chromatography (HPLC)

HPLC can help characterize peptide purity and degradation-related impurities.

Liquid Chromatography–Mass Spectrometry (LC-MS)

LC-MS can support molecular identity confirmation.

Mass Spectrometry

Mass analysis can verify consistency with the expected peptide molecular mass.

Disulfide Integrity

Analytical testing may be used to confirm the expected oxidized peptide structure.

Peptide Content

Content analysis helps distinguish the quantity of oxytocin from the total mass of formulation material.

Stability Testing

Stability studies help establish appropriate conditions for research materials.

Certificate of Analysis

A batch-specific COA should identify the compound and provide relevant analytical results.

A purity percentage alone does not establish that a product meets pharmaceutical standards.

Scientific Evidence and Research Limitations

Well-Established Findings

• Oxytocin is an endogenous nine-amino-acid peptide hormone.

• It contains a disulfide bridge between Cys¹ and Cys⁶.

• Its molecular formula is C₄₃H₆₆N₁₂O₁₂S₂.

• Its molecular weight is approximately 1,007.19 g/mol.

• It is synthesized primarily in the hypothalamus.

• The posterior pituitary releases oxytocin into circulation.

• OXTR is its principal receptor.

• OXTR commonly signals through Gq/11, PLC, IP₃ and calcium pathways.

• Oxytocin stimulates uterine smooth muscle contraction.

• Oxytocin mediates milk ejection.

• Approved oxytocin medicines have established obstetric applications.

Areas Requiring Further Research

• The precise relationship between central and peripheral oxytocin signaling.

• Individual differences in social behavioral responses.

• The reproducibility of intranasal oxytocin findings.

• Its clinical utility in psychiatric conditions.

• The long-term effects of experimental central oxytocin exposure.

• Receptor signaling differences across tissues.

• The therapeutic significance of metabolic research findings.

• The influence of receptor desensitization on prolonged responses.

Potential Oxytocin Research Applications

Oxytocin may be relevant to appropriately controlled laboratory investigations involving:

• Oxytocin receptor pharmacology

• OXTR gene expression

• GPCR signaling

• Gq/11 pathways

• PLC / IP₃ / DAG signaling

• Intracellular calcium regulation

• Smooth muscle contractility

• Myometrial physiology

• Uterine receptor expression

• Lactation and mammary cell biology

• Hypothalamic neuroendocrinology

• Posterior pituitary physiology

• Neuropeptide release

• Neuronal plasticity

• Social cognition

• Social reward processing

• Maternal behavior

• Stress-associated neural signaling

• Amygdala-associated responses

• Intranasal peptide research

• Receptor desensitization

• Oxytocin–vasopressin receptor comparisons

• Peptide stability

• Disulfide bond chemistry

• Analytical peptide characterization

These research applications should not be confused with approved clinical indications.

Oxytocin Research Overview

Compound Name: Oxytocin

Alternative Names: OXT / OT / Oxytocinum

Classification: Cyclic Nonapeptide Hormone

Amino Acid Length: 9

Sequence: Cys–Tyr–Ile–Gln–Asn–Cys–Pro–Leu–Gly–NH₂

One-Letter Sequence: CYIQNCPLG-NH₂

Molecular Formula: C₄₃H₆₆N₁₂O₁₂S₂

Molecular Weight: Approximately 1,007.19 g/mol

CAS Number: 50-56-6

PubChem CID: 439302

Structural Feature: Cys¹–Cys⁶ Disulfide Bond

Principal Receptor: OXTR

Main Signaling Pathway: Gq/11–PLC–IP₃–Ca²⁺

Primary Research Fields: Reproductive Physiology / Neuroendocrinology / Social Neuroscience

Approved Human Medical Uses: Yes, for specific indications and authorized pharmaceutical products

Research Product Intended Use: Laboratory Research Only

ICAME Pharmacy Product Information

Product Name: Oxytocin

Brand: ICAME Pharmacy

Product Category: Research Peptide

Research Classification: Cyclic Nonapeptide Hormone

Principal Research Target: Oxytocin Receptor (OXTR)

Research Areas: Reproductive Biology / Neuroendocrine Signaling / Cellular Pharmacology / Neuroscience

Intended Use: Laboratory Research & Development Only

Product specifications should be confirmed using the actual product label and batch-specific analytical documentation.

Relevant quality information includes:

• Verified amino acid sequence

• Molecular identity

• Disulfide bond integrity

• Peptide purity

• Peptide content

• Impurity profile

• Counterion composition, where applicable

• Analytical methodology

• Certificate of Analysis (COA)

• Batch or lot identification

• Validated stability and storage conditions

No claims of pharmaceutical quality, sterility, injectable suitability or clinical authorization should be made without appropriate supporting evidence.

Important Research Use Notice

FOR RESEARCH USE ONLY (RUO)

This ICAME Pharmacy product is intended exclusively for legitimate laboratory, analytical and scientific research purposes.

Not for human or veterinary use. Not for diagnostic, therapeutic, obstetric, psychiatric, performance-enhancing, sexual enhancement or other clinical purposes. Not for direct administration to humans or animals.

Oxytocin is a biologically active peptide hormone.

Approved pharmaceutical oxytocin products are used in specific medical settings under professional supervision.

However, research-grade oxytocin is not equivalent to an approved medicine.

Inappropriate exposure can cause significant physiological effects, including uterine stimulation and other systemic complications.

Experimental findings involving social behavior, stress or cognition do not establish clinical efficacy for those applications.

Information presented on this page is intended solely for scientific and educational purposes and does not constitute medical advice, prescribing information, dosage guidance or instructions for human use.

About ICAME Pharmacy

ICAME Pharmacy provides specialized research products for professional laboratory and scientific applications.

Our portfolio focuses on compounds relevant to peptide science, receptor pharmacology, reproductive biology, molecular signaling and neuroendocrine research.

We emphasize accurate product identification, responsible research use, scientific transparency and clear communication of evidence limitations.

For batch-specific analytical documentation and product inquiries, please contact ICAME Pharmacy.

Frequently Asked Questions About Oxytocin

What is oxytocin?

Oxytocin is a naturally occurring cyclic nine-amino-acid peptide hormone involved in reproductive physiology, lactation and neuroendocrine signaling.

Is oxytocin a peptide?

Yes. Oxytocin is a nonapeptide containing nine amino acid residues.

What is the amino acid sequence of oxytocin?

Cys–Tyr–Ile–Gln–Asn–Cys–Pro–Leu–Gly–NH₂.

What is the molecular formula of oxytocin?

C₄₃H₆₆N₁₂O₁₂S₂.

What is the molecular weight of oxytocin?

Approximately 1,007.19 g/mol.

What is the CAS number of oxytocin?

50-56-6.

Is oxytocin a cyclic peptide?

Yes. A disulfide bridge connects its first and sixth cysteine residues.

Where is oxytocin produced?

Oxytocin is synthesized primarily in hypothalamic neurons.

Where is oxytocin released?

It is released into the bloodstream from the posterior pituitary and also participates in signaling within the central nervous system.

What receptor does oxytocin activate?

The oxytocin receptor, OXTR.

What is the main oxytocin signaling pathway?

OXTR commonly activates Gq/11-associated phospholipase C signaling, leading to IP₃-mediated calcium responses.

What does oxytocin do during childbirth?

Oxytocin stimulates uterine smooth muscle contractions.

What is the role of oxytocin in breastfeeding?

Oxytocin triggers contraction of mammary myoepithelial cells, producing the milk ejection reflex.

Is oxytocin the same as prolactin?

No. Prolactin is primarily associated with milk synthesis, while oxytocin is important for milk ejection.

Is oxytocin the same as vasopressin?

No. They are related but distinct peptide hormones with different principal receptors and physiological functions.

Is oxytocin the love hormone?

Oxytocin participates in social and attachment-associated processes, but the term “love hormone” oversimplifies its complex biology.

Does oxytocin increase trust?

Some studies have reported context-dependent effects, but oxytocin does not reliably increase trust in all people or situations.

Has intranasal oxytocin been studied?

Yes. Intranasal oxytocin has been investigated in human neuroscience and behavioral research.

Is oxytocin an approved medicine?

Yes. Specific pharmaceutical oxytocin products are approved for certain obstetric indications.

Is research-grade oxytocin an approved medicine?

No. Research-grade oxytocin is not automatically an approved pharmaceutical product.

Is ICAME Pharmacy Oxytocin intended for human use?

No. ICAME Pharmacy Oxytocin is intended strictly for laboratory research and development purposes.