PT-141
A cyclic heptapeptide melanocortin receptor agonist studied in laboratory and clinical settings for melanocortin-mediated arousal mechanisms
About PT-141
PT-141 (Bremelanotide, CAS 189691-06-3) is a cyclic heptapeptide derived from Melanotan II that selectively activates melanocortin receptors MC3R and MC4R. It has been studied in preclinical and clinical research for melanocortin-mediated central nervous system signaling.
PT-141 traces its origins to research at the University of Arizona in the 1980s, where Dr. Mac Hadley and Dr. Victor Hruby were investigating analogs of α-melanocyte-stimulating hormone (α-MSH). Their work on Melanotan II had unexpectedly produced reports of increased arousal in male research subjects, an observation that led to the systematic search for a melanocortin compound with selective central nervous system activity.
Researchers at Palatin Technologies identified PT-141 as a more selective derivative of Melanotan II, with reduced activity at peripheral melanocortin-1 receptors (responsible for melanogenesis) and retained activity at the central MC3R and MC4R receptors implicated in arousal pathways. Unlike phosphodiesterase-5 inhibitors that act on vascular tissue, PT-141 was characterized as the first compound to influence sexual response through a CNS-mediated mechanism.
PT-141 has been the subject of extensive preclinical and clinical investigation, with Phase 3 trials published in Obstetrics & Gynecology in 2019 examining its effects in research populations. As an active research tool, the compound continues to be widely used in studies investigating melanocortin receptor signaling and neuroendocrine pathways.
Quick Facts
| CAS Number | 189691-06-3 |
|---|---|
| Molecular Formula | C₅₀H₆₈N₁₄O₁₀ |
| Molar Mass | 1025.2 g/mol |
| Sequence | 7 amino acids (cyclic heptapeptide) |
| Form | Lyophilized powder |
| Purity | 99%+ (HPLC verified) |
| Third-Party Testing | Freedom Diagnostics (COA included) |
| Storage | Room temp 3–4 months; refrigerate post-reconstitution |
| Price (from) | $50.00 USD |
| SKU | PF-PT141-10MG |
How PT-141 Works
Preclinical and clinical studies have examined PT-141's mechanism as a melanocortin receptor agonist that primarily acts on MC3R and MC4R in the central nervous system, particularly within the medial preoptic area of the hypothalamus.
MC3R/MC4R Receptor Activation
PT-141 binds to and activates melanocortin receptors 3 and 4 (MC3R and MC4R) in the central nervous system. These G protein-coupled receptors are concentrated in the hypothalamus and play roles in energy balance, neuroendocrine signaling, and arousal pathways studied in preclinical research.
Hypothalamic Signaling
Preclinical studies have localized PT-141's activity to the medial preoptic area (mPOA) of the hypothalamus, a region implicated in autonomic and behavioral arousal. Activation of melanocortin receptors in this region has been associated with downstream dopaminergic and oxytocinergic signaling in research models.
CNS-Mediated Mechanism
Unlike vascular-acting compounds, PT-141 produces its observed effects through central rather than peripheral mechanisms. Research has confirmed this distinction by demonstrating PT-141 activity in models that bypass peripheral vascular pathways entirely.
Selectivity vs. MC1R Agonism
Compared to its parent compound Melanotan II, PT-141 has reduced activity at MC1R, the receptor responsible for melanogenesis. This selectivity profile makes PT-141 a useful tool for studying central melanocortin signaling without the confounding pigmentation effects of broader-spectrum MC agonists.
Frequently Asked Questions
- What is PT-141?
- PT-141 (Bremelanotide, CAS 189691-06-3) is a cyclic heptapeptide derived from Melanotan II that selectively activates melanocortin receptors MC3R and MC4R. It has been studied in preclinical and clinical research for melanocortin-mediated central nervous system signaling.
- What is the CAS number for PT-141?
- The CAS number for PT-141 is 189691-06-3.
- What purity is Peptide Foundry's PT-141?
- Peptide Foundry's research peptides are manufactured to 99%+ purity. Every batch is verified by an independent third-party laboratory (Freedom Diagnostics) using high-performance liquid chromatography (HPLC) for purity and identity, Limulus amebocyte lysate (LAL) assay for bacterial endotoxin, and inductively coupled plasma mass spectrometry (ICP-MS) for heavy-metal contamination. A Certificate of Analysis is published for every product and batch.
- How should PT-141 be stored?
- Lyophilized (freeze-dried) peptides are stable at room temperature for 3–4 months. Once reconstituted with bacteriostatic water, store refrigerated (2–8 °C) and use within 30 days. Keep away from direct light and extreme temperatures.
- Does PT-141 ship with a Certificate of Analysis?
- Yes. Every batch of every product ships with a Certificate of Analysis from Freedom Diagnostics, an independent third-party analytical laboratory. The COA documents HPLC purity, peptide identity, endotoxin testing, and heavy-metals screening.
- Is PT-141 sold for human use?
- No. All products sold by Peptide Foundry are strictly for in-vitro research and laboratory use only (RUO). They are not intended for human or animal consumption, therapeutic use, or diagnostic application.
Scientific References
- Diamond LE, et al. An effect on the subjective sexual response in premenopausal women with sexual arousal disorder by bremelanotide (PT-141), a melanocortin receptor agonist. J Sex Med. 2006;3(4):628-638. PubMed: 16839319
- Pfaus JG, et al. Selective facilitation of sexual solicitation in the female rat by a melanocortin receptor agonist. Proc Natl Acad Sci USA. 2004;101(27):10201-10204. PubMed: 15226502
- Kingsberg SA, et al. Bremelanotide for the Treatment of Hypoactive Sexual Desire Disorder: Two Randomized Phase 3 Trials. Obstet Gynecol. 2019;134(5):899-908. PubMed: 31599840
- Molinoff PB, et al. PT-141: a melanocortin agonist for the treatment of sexual dysfunction. Ann N Y Acad Sci. 2003;994:96-102. PubMed: 12851303
This product is sold strictly for in-vitro research use only (RUO). It is not intended for human or animal consumption, therapeutic use, or diagnostic application.