What is PT-141 10MG?

PT-141, also known as bremelanotide, is a synthetic melanocortin peptide analog derived from α-melanocyte-stimulating hormone that selectively activates central melanocortin receptors, particularly MC3R and MC4R, to influence sexual motivation and arousal pathways in the brain. Unlike phosphodiesterase-5 inhibitors, PT-141 does not act on vascular mechanisms but instead modulates neurochemical signaling involved in desire and arousal responses. It has been investigated in controlled research settings for its effects on sexual behavior in both males and females, with observed central nervous system mediated activity rather than direct peripheral action.

Introduction

PT-141, commonly referred to as bremelanotide, is a laboratory-synthesized peptide that originated from structure activity optimization of melanocortin signaling molecules. It belongs to a class of compounds designed to interact with specific receptors involved in neurobehavioral regulation, distinguishing it from agents that primarily target peripheral physiological pathways. Its molecular design allows it to cross central regulatory circuits, making it a subject of interest in experimental and pharmacological research contexts focused on central signaling mechanisms.
Within scientific literature, PT-141 has been explored for its receptor selectivity, signaling bias, and central nervous system engagement under controlled conditions. Research discussions often emphasize its unique interaction profile within the melanocortin receptor family and its ability to influence centrally mediated response patterns without relying on direct hormonal or vascular modulation. As a result, PT-141 continues to be referenced in academic and investigational frameworks examining neuropeptide-based modulation strategies, rather than as a generalized therapeutic agent

Mechanism of action

Central Melanocortin Receptor Binding

This receptor engagement occurs predominantly within discrete brain nuclei where melanocortin signaling contributes to integrative neuroregulatory processes. The interaction reflects ligand receptor specificity that supports controlled activation without broad systemic involvement, allowing focused modulation of central signaling environments.

Second-Messenger Pathway Activation

Signal propagation following receptor engagement involves amplification through intracellular mediator systems that regulate transcriptional responsiveness and synaptic signaling efficiency. These cascades contribute to adaptive changes in neuronal responsiveness rather than immediate peripheral physiological effects.

Hypothalamic–Limbic Network Integration

Neural communication across these regions facilitates coordinated processing of internal signals, enabling synchronized responses across motivation-related and autonomic control centers. Such integration underscores the importance of circuit-level coordination in centrally mediated signaling.

Receptor-Driven Functional Signaling Profile

This mechanism illustrates a model of targeted neuropeptide signaling in which functional outcomes arise from receptor-selective activation and controlled intracellular communication dynamics rather than diffuse biological stimulation.

Chemical Structure of PT-141 10MG

Sequence: Ac-Nle-Asp(1)-His-D-Phe-Arg-Trp-Lys (1)

Molecular Formula: C50H68N14O10

Molecular Weight: 1025.182 g/mol

PubChem CID: 9941379

CAS Number: 189691-06-3

Properties

Monoisotopic Mass: 1024.52428442

Polar Area: 379

Complexity: 1950

XLogP: 0.7

Heavy Atom Count: 74

Hydrogen Bond Donor Count: 13

Hydrogen Bond Acceptor Count: 12

Rotatable bond count: 17

Pubchem LCSS : Bremelanotide Laboratory Chemical Safety Summary

Identifiers

Field
values
CID
9941379
InChl
InChl=1S/C50H68N14010/c1-3-4-16-35(58-29(2)65)43(67)64-41-25-42(66)54-20-11-10-18-37(49(73)74)60-46(70)39(23-31-26-56-34-17-9-8-15-33(31)34)62-44(68)36(19-12-21-55-50(51)52)59-45(69)38(22-30-13-6-5-7-14-30)61-47(71)40(63- 48(41)7224-32-27-53-28-57-32/h5-9,13-15,17,26-28,35-41,56H,3-4, 10-12,16, 18-25H2,1-2H3, (H,53,57) (H,54,66) (H,58,65) (H,59,69)(H,60,70)(H,61,71) (H,62,68)(H,63,72)(H,64,67) (H,73,74) (H4,51,52,55)/t35-,36-,37-, 38+, 39-,40-,41-/m0/s1
InChiKey
FFHBJDQSGDNCIV-MFVUMRCOSA-N
Isometric SMILES
CCCCIC@@H](C(=O)N[C@H]1CC(=O)NCCCC[C@H](NC(=O)[C@@H](NC(=0)

[C@@H|NC(=O)[C@H]NC(=0)[C@@H](NC1=0)CC2=CN=CN2)CC3=CC

=CC=C3)CCCN=C(N)N)CC4=CNC5=CC=CC=C54)C(=0)0)NC(=0)c

Canonical MILES
CCCCC(C(=O)NC1CC(=O)NCCCCC(NC(=0)C(NC(=0)C(NC(=0)C(NC(=O)C(NC1=0)CC2=CN=CN2)CC3=CC=CC=C3)CCCN=C(N)N)CC4=CNC5=CC=CC=C54)C(=0)OJNC(=0)C
JPAC Name
(35,65,9R,12S, 15S,23S)-15-[[(2S)-2-acetamidohexanoyl]amino]-9-

benzyl-6-[3-diaminomethylideneamino)propyl]-12-(1H-imidazol-5-ylmethyl)-3-

(1H-indol-3-ylmethyl)-2,5,8, 11, 14,17-hexaoxo-1,4,7,10, 13, 18-hexazacyclotricosane-23-carboxylic acid

What Are the Effects of PT-141 10MG?

PT-141 as a Modulator of Sexual Arousal

PT-141 has been investigated for its role in centrally mediated sexual arousal pathways, primarily through activation of melanocortin receptors, with particular emphasis on MC4R signaling within hypothalamic and limbic circuits involved in motivational behavior [1,2]. Preclinical studies have demonstrated that melanocortin receptor agonism is associated with measurable changes in sexual behavior and arousal responses in animal models, supporting a mechanism that operates independently of peripheral vascular modulation [3,4].

Clinical investigations in men with erectile dysfunction unresponsive to phosphodiesterase type-5 inhibitors have reported that intranasal administration of PT-141 produced erections sufficient for intercourse in a subset of participants, with outcomes showing a clear dose-dependent relationship [5]. These findings highlighted the relevance of centrally acting compounds for research into sexual dysfunction where neurogenic mechanisms may predominate.

The figure shows a dose-dependent increase in duration of erectile response following PT-141 administration compared with placebo. Higher doses (≥3.0 mg) are associated with significantly prolonged erectile time, while the inset indicates a reduction in time to first erection as dose increases, supporting a centrally mediated, dose-responsive effect.

PT-141 has also been evaluated in female sexual dysfunction research, including randomized dose-finding studies in premenopausal women that examined validated psychometric endpoints related to desire and arousal [6,7]. Subsequent development efforts expanded interest in subcutaneous formulations, prompting further investigation into pharmacokinetic behavior, trial design considerations, and outcome assessment strategies [8]. Collectively, ongoing translational research continues to explore the broader role of melanocortin signaling in reward processing and motivational states, providing mechanistic context for PT-141–associated behavioral observations [9,10].

Hemorrhagic Shock Modulation

PT-141 related melanocortin agonists have been explored within hemorrhagic shock and acute hypovolemia research paradigms, based on their capacity to engage central and peripheral melanocortin receptor signaling networks. Particular attention has been directed toward MC1R- and MC4R-associated pathways, which are implicated in the regulation of inflammatory responses, autonomic balance, and tissue resilience during ischemic stress conditions [11,12]. These mechanisms have positioned melanocortin peptides as experimental tools for studying systemic responses to severe blood loss rather than as conventional volume replacement strategies.

Preclinical investigations have suggested that activation of melanocortin receptors may modulate cardiovascular reflexes, cytokine release, and microcirculatory function following hemorrhage, thereby influencing short-term survival and organ perfusion in animal models [13,14]. Within this research space, a structurally modified analog, commonly cited as PL-6983, has been described as exhibiting enhanced stability and receptor interaction profiles suitable for experimental evaluation under shock conditions [15]. Such analogs have been examined for their ability to attenuate hypotension and metabolic derangements associated with acute blood volume depletion.

Additional studies have proposed that melanocortin-based signaling may interact with hypothalamic pituitary adrenal axis activity and sympathetic outflow, contributing to coordinated systemic adaptations during hemorrhagic stress [16,17]. Although these findings remain confined to experimental and translational research contexts, they have expanded scientific understanding of how melanocortin receptor modulation influences physiological responses to ischemia and trauma, independent of direct fluid resuscitation or vasopressor mechanisms.

PT-141 and Infection

It has been examined in the context of infectious and inflammatory disease models, reflecting its broader role in innate immune regulation. Experimental studies have demonstrated that melanocortin peptides can influence host–pathogen interactions by modulating immune cell activity rather than exerting direct antimicrobial effects. In a rat model of Candida albicans associated vaginitis, the synthetic melanocortin peptide CKPV was evaluated for its capacity to alter inflammatory responses and fungal burden, with findings suggesting involvement of macrophage phenotype regulation and cytokine signaling pathways [18,19].

Further investigations into melanocortin biology have highlighted its relevance in infection-associated inflammation, particularly through effects on macrophage polarization, neutrophil recruitment, and resolution-phase immune responses [20,21]. By engaging melanocortin receptors expressed on immune cells, these peptides have been shown to shift inflammatory profiles toward regulatory or reparative states in preclinical models, thereby supporting tissue homeostasis during infectious challenges [22]. Collectively, this body of work has reinforced interest in melanocortin pathways as adjunct research targets within infection and inflammation biology, offering mechanistic insight into immune modulation independent of conventional antimicrobial strategies [23,24].

PT-141 and Cancer/Photoprotection

It has also been extensively investigated within photoprotection and dermatologic oncology research, owing to its central role in regulating melanogenesis, ultraviolet (UV) response pathways, and genomic stability in cutaneous cells. Experimental studies indicate that activation of MC1R enhances nucleotide excision repair capacity, reduces oxidative DNA damage, and modulates cellular stress responses following UV exposure, thereby contributing to protective mechanisms against mutagenesis [25,26]. Genetic polymorphisms affecting MC1R function have been correlated with impaired pigmentation responses and elevated susceptibility to melanoma and non-melanoma skin cancers, independent of UV exposure intensity [27,28]. These observations have sustained interest in melanocortin pathway modulation as a framework for understanding individual variability in skin cancer risk and for exploring photoprotective signaling mechanisms relevant to prevention-oriented research [29,30].

Area of research

PT-141 has garnered significant interest in investigations of sexual dysfunction through its modulation of neurobehavioral pathways, primarily via activation of melanocortin receptors such as MC3R and MC4R in the central nervous system.(31,32) In addition to this primary focus, melanocortin receptor biology opens broader experimental opportunities. For instance, dysfunction in MC4R signaling has been linked to certain forms of early-onset obesity, and PT-141 provides a valuable agonist framework for exploring melanocortin pathways in energy homeostasis and appetite regulation.(33,34)3,4 Similarly, MC1R signaling has been implicated in mechanisms related to pain modulation, inflammation, renal pathology, and various immune-related processes, positioning melanocortin agonists like PT-141 as useful tools for studying these interconnected pathways.(35,36)

In preclinical models (e.g., mice), PT-141 demonstrates favorable characteristics, including minimal observed adverse effects, low oral bioavailability, and excellent subcutaneous bioavailability.(37) However, dosage extrapolations from per-kg body weight in mice do not directly translate to humans due to species-specific differences in pharmacokinetics and receptor dynamics.(38)

References

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