PT-141 Bremelanotide

Research Benefits

• Melanocortin Pathway Research — PT-141 (Bremelanotide) is a cyclic heptapeptide melanocortin receptor agonist, providing a valuable tool for studying MC3R and MC4R signaling in central nervous system models.
• Sexual Function Studies — Extensive research has explored PT-141's effects on sexual arousal and desire pathways, demonstrating a mechanism distinct from peripheral vasodilators like PDE5 inhibitors.
• Central Nervous System Activity — Unlike peripherally acting compounds, PT-141 exerts effects through hypothalamic melanocortin circuits, making it useful for studying CNS-mediated behavioral responses.
• Appetite & Energy Homeostasis — MC4R agonism links PT-141 to energy balance research, with studies examining its effects on feeding behavior and metabolic rate.

Mechanism of Action

Bremelanotide (PT-141) is a synthetic cyclic heptapeptide derived from the melanocortin peptide Melanotan II. It functions as an agonist at melanocortin receptors MC3R and MC4R, both of which are expressed in the hypothalamus and limbic system.

MC4R Agonism: PT-141 binds and activates the melanocortin-4 receptor in the medial preoptic area and paraventricular nucleus of the hypothalamus. This activation triggers downstream signaling cascades involving cAMP and protein kinase A (PKA), modulating neuronal pathways associated with arousal and motivational behavior.

Distinct from PDE5 Inhibitors: PT-141's mechanism is centrally mediated rather than peripherally vascular. It does not depend on nitric oxide/cGMP pathways, making it mechanistically distinct from sildenafil-class compounds.

Dopaminergic Interaction: MC4R activation by PT-141 has been shown to increase dopamine release in the mesolimbic pathway, which may contribute to its effects on motivation and reward-related behaviors.

Oxytocin Release: Studies suggest PT-141 may stimulate oxytocin release from the paraventricular nucleus, adding a neuroendocrine component to its behavioral effects.

Research Protocol

The following information is derived from published research literature and is intended for reference in research settings only.

Reconstitution

Reconstitute lyophilized PT-141 with bacteriostatic water. Standard reconstitution yields solutions of 1-2 mg/mL.

Research Dosing (from published studies)

• In vivo (rodent models): 0.5-1.0 mg/kg subcutaneous injection has been used in behavioral studies.
• Larger animal models: 0.01-0.03 mg/kg SC, with behavioral assessments at 30-60 minutes post-administration.
• Intranasal (research): Some studies have explored intranasal delivery as an alternative route.

Experimental Timing

Peak plasma concentrations in animal models occur approximately 30 minutes after subcutaneous administration. Behavioral observations are typically recorded during a 1-4 hour post-dose window.

Storage

Store lyophilized peptide at -20°C. Reconstituted solutions at 2-8°C, use within 21 days.

Safety & Handling

Research Use Only. This product is not intended for human or veterinary diagnostic or therapeutic use.

Storage Conditions

• Lyophilized: -20°C, protected from light
• Reconstituted: 2-8°C, use within 21 days
• Avoid repeated freeze-thaw cycles

Known Considerations from Literature

• Transient nausea has been reported in research settings at higher dose ranges, likely mediated through area postrema MC4R activation.
• PT-141 may cause transient facial flushing in animal models due to melanocortin-mediated vasodilation.
• Potential blood pressure effects have been noted; hemodynamic monitoring is recommended in cardiovascular-sensitive models.
• Co-administration with other melanocortin agonists should be approached with caution to avoid receptor overstimulation.

Handling

Use standard laboratory PPE. Handle in a clean, sterile environment. Dispose of unused material per institutional guidelines.

Frequently Asked Questions

What is PT-141?

PT-141, also known as Bremelanotide, is a synthetic cyclic heptapeptide melanocortin receptor agonist. It was developed from Melanotan II and is used in research exploring melanocortin signaling pathways in the CNS.

How does PT-141 differ from PDE5 inhibitors in research?

PT-141 acts through central melanocortin receptors (MC3R/MC4R) in the hypothalamus, while PDE5 inhibitors work peripherally through the nitric oxide/cGMP pathway. This makes PT-141 a unique tool for studying centrally mediated behavioral pathways.

What purity is this product?

BeaCapra PT-141 is manufactured to ≥99% purity as verified by HPLC and mass spectrometry. A COA is provided with every order.

How should PT-141 be reconstituted?

Reconstitute with bacteriostatic water by gently directing the solvent down the side of the vial. Swirl gently; do not shake or vortex vigorously.

What is the shelf life?

Lyophilized PT-141 is stable for 24+ months when stored at -20°C. Reconstituted solutions should be used within 21 days when stored at 2-8°C.