Oxytocin

Oxytocin Peptide Overview

Oxytocin is a specialized nonapeptide hormone and neuropeptide that plays a fundamental role in the mammalian endocrine and central nervous systems. Synthesized primarily within the magnocellular neurosecretory cells of the hypothalamus, it is transported to the posterior pituitary for systemic release. Beyond this classical pathway, oxytocin is expressed in various peripheral tissues including the uterus, placenta, amnion, corpus luteum, and testes. The peptide is initially synthesized as a larger inactive precursor, which undergoes sequential enzymatic processing to yield the active nine-amino acid sequence.

Recent advancements in peptide research have identified additional sites of oxytocin synthesis, such as the adrenal medulla, thymus, and pancreas. This broad distribution suggests that oxytocin functions through autocrine or paracrine mechanisms to regulate local tissue homeostasis. It acts via the oxytocin receptor, a G-protein-coupled receptor, to initiate intracellular signaling cascades that influence everything from smooth muscle contraction to complex behavioral modulation.

Oxytocin Peptide Structure

The molecular architecture of oxytocin is defined by a six-residue disulfide ring and a three-residue C-terminal tail. This cyclic structure is vital for receptor binding and biological stability.

Structure Solution Formula: C43H66N12O12S2

Peptide Sequence: Cysteine-Tyrosine-Isoleucine-Glutamine-Asparagine-Cysteine-Proline-Leucine-Glycinamide

Technical Parameter

Specification Value

Sequence Length

9 Amino Acids

Molecular Weight

1007.2 Daltons

Appearance

Lyophilized White Powder

Solubility

Water Soluble

Purity Level

Greater than 98 percent

CAS Number

50-56-6

Oxytocin Peptide Research

Oxytocin in Wound Healing

Oxytocin has been identified as a significant factor in the acceleration of dermal repair. It modulates the inflammatory phase by influencing the production of specific cytokines. In clinical research observing interpersonal interactions, subjects with higher oxytocin levels demonstrated enhanced wound contraction and faster healing times. Conversely, psychological stress, which suppresses oxytocin, can lead to a 40 percent reduction in healing efficiency. The peptide's ability to lower systemic cortisol levels contributes to a pro-healing environment within the skin's extracellular matrix.

Studying Oxytocin in Cardiovascular Risk

The presence of oxytocin receptors in the heart and vascular endothelium suggests a protective role in cardiovascular health. Research indicates that oxytocin can lower blood pressure and reduce the accumulation of adipose tissue, both of which are primary risk factors for cardiovascular disease. In animal models of myocardial infarction, the administration of oxytocin has been shown to protect heart muscle cells from oxidative damage. Furthermore, long-term exposure to the peptide may prevent the development of dilated cardiomyopathy by supporting the regeneration of cardiac tissues.

Diabetes Management

Oxytocin influences metabolic health by improving insulin sensitivity and promoting glucose uptake in skeletal muscle. Research in animal models shows that oxytocin deficiency is often a precursor to obesity and metabolic dysfunction. In trials involving insulin-resistant subjects, oxytocin administration significantly improved lipid profiles and reduced body fat percentages. Specifically, in obese mice, oxytocin treatment led to improved glucose tolerance, while lean mice remained unaffected, suggesting the peptide targets metabolic imbalances specifically.

Oxytocin and Old Muscle

Age-related muscle loss, or sarcopenia, is partially attributed to the decline of regenerative signaling molecules. Research from UC Berkeley demonstrated that oxytocin levels decrease with age, leading to a reduction in muscle stem cell activation. When oxytocin was administered to aged mice, their muscle regeneration capacity improved by approximately 80 percent, reaching levels similar to younger mice. This suggests that the oxytocin pathway is essential for maintaining the structural integrity of skeletal muscle throughout the aging process.

Article Author

This review was compiled and organized by Dr. Sue Carter, Ph.D., an esteemed behavioral neurobiologist known globally for her groundbreaking studies on oxytocin and social attachment. Dr. Carter’s research has been pivotal in redefining oxytocin’s dual role as both a hormone and a neuromodulator.

Scientific Journal Author

Dr. Thomas R. Insel, M.D., is a distinguished neuroscientist and former Director of the National Institute of Mental Health (NIMH). He is best known for his foundational research on oxytocin, vasopressin, and affiliative behavior.

Reference Citations

1. du Vigneaud V, et al. The synthesis of an octapeptide amide with the hormonal activity of oxytocin. J Am Chem Soc. 1953;75(19):4879-4880.
2. Gimpl G, Fahrenholz F. The oxytocin receptor system: structure, function, and regulation. Physiol Rev. 2001;81(2):629–683.
3. Insel TR. The challenge of translation in social neuroscience: a review of oxytocin, vasopressin, and affiliative behavior. Neuron. 2010;65(6):768-779.
4. Carter CS. Oxytocin pathways and the evolution of human behavior. Annu Rev Psychol. 2014;65:17-39.
5. Heinrichs M, et al. Neuroendocrine mechanisms of stress and oxytocin. Biol Psychiatry. 2009;65(9):774-782.
6. Neumann ID, et al. Central oxytocin mechanisms in stress and anxiety. Prog Brain Res. 2008;170:143–159.
7. Lee HJ, et al. Oxytocin receptor signaling in social and emotional behavior. Prog Neurobiol. 2009;88(2):127-151.
8. Leng G, Sabatier N. Measuring oxytocin and vasopressin: bioassays and immunoassays. J Neuroendocrinol. 2016;28(4).
9. Meyer-Lindenberg A, et al. Oxytocin and human social behavior. Science. 2011;333(6039):1148-1151.
10. Peters S, et al. Oxytocin and the stress response system. Front Neuroendocrinol. 2018;51:14-30.

Storage

Storage Instructions

All products are provided as a lyophilized (freeze-dried) powder. This format ensures stability for 3 to 4 months at room temperature. After reconstitution with bacteriostatic water, the solution must be stored in a refrigerator (below 4 degrees Celsius) and used within 30 days to maintain biological activity.

Best Practices For Storing Peptides

For extended storage exceeding several months, it is recommended to keep peptides in a freezer at -80 degrees Celsius. Maintaining a consistent temperature is critical; avoid frost-free freezers as they undergo periodic warming cycles which can lead to peptide degradation.

Preventing Oxidation and Moisture Contamination

Oxidation can significantly reduce the efficacy of oxytocin. Always allow the vial to reach room temperature before opening to avoid moisture condensation. Reseal the vial immediately after use and, if possible, store under an inert gas like nitrogen.

Storing Peptides In Solution

Peptides in solution are highly susceptible to degradation. If storage in liquid form is necessary, use a sterile buffer at pH 5 to 6 and divide the solution into small aliquots. This minimizes the number of freeze-thaw cycles the peptide must undergo.

Peptide Storage Containers

High-quality, chemically resistant glass vials are the gold standard for peptide storage. While plastic vials made of polypropylene are often used for shipping, transferring the peptide to glass for long-term storage can help maintain purity and prevent air permeability.

Peptide Storage Guidelines: General Tips

• Keep the peptide in a dark, cool, and dry location.
• Avoid frequent temperature fluctuations.
• Protect the peptide from direct exposure to UV light.
• Do not store in a liquid state for long periods.