Source comparison
Key Comparisons: PT-141 vs MT-II vs Alpha-MSH in Sexual Arousal Research
MT-II (Melanotan-II, cyclic [Nle⁴, D-Phe⁷]-alpha-MSH): Non-selective melanocortin agonist; MC1R (tanning, Ki ~0.2nM), MC3R (Ki ~0.3nM), MC4R (Ki ~0.4nM), MC5R (Ki ~0.6nM). Strong spontaneous erection in rodent models (via MC4R) but tanning (via MC1R) is a conf
This comparison does not assign a generated winner or score.
- MT-II (Melanotan-II, cyclic [Nle⁴, D-Phe⁷]-alpha-MSH): Non-selective melanocortin agonist; MC1R (tanning, Ki ~0.2nM), MC3R (Ki ~0.3nM), MC4R (Ki ~0.4nM), MC5R (Ki ~0.6nM). Strong spontaneous erection in rodent models (via MC4R) but tanning (via MC1R) is a confounding pharmacological effect absent in PT-141. PT-141’s selective MC4R/MC3R profile (minimal MC1R) allows sexual arousal research without melanocyte activation confound.
- Alpha-MSH (13 AA, endogenous): All MC receptors, Kd ~0.5-2nM. CNS half-life ~30min (enzymatic degradation by neprilysin, IDE, ACE). PT-141 cyclic lactam scaffold resists proteolysis: plasma t½ ~2.7h (human i.v.); CNS activity duration ~3-4h (behavioural readout in rodent). PT-141 is therefore the preferred research tool over alpha-MSH for sustained melanocortin CNS activation studies.
- PT-141 vs PDE5i (mechanistic distinction for research design): PDE5i effect requires pre-existing peripheral NO tone — not useful for studying central arousal neurobiology or in models with peripheral autonomic neuropathy. PT-141 is the appropriate tool for central MC4R-dopaminergic arousal circuit research, for hypogonadism models where reduced central drive is the primary deficit, and for FSAD models where peripheral vascular NO is insufficient to explain the full arousal deficit.