Comparison
Melanotan II vs. Octreotide
Two peptides side-by-side — identity, evidence base, legal status and known adverse events.
Identity
Category
Research other
Research other
CAS no.
121062-08-6
83150-76-9
Molecular weight
1024.18 g/mol
1019.24 g/mol
Half-life
1 h
1.7 h
Sequence
Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr(ol)Mechanism of action
Melanotan II
Melanotan II binds non-selectively to all five melanocortin-receptor subtypes (MC1R-MC5R). Via MC1R in melanocytes, eumelanin synthesis is stimulated (pigmenting effect). Via MC4R and MC3R in the CNS, appetite, sexual function and blood pressure are modulated. The cyclic structure and D-amino acids increase stability compared to natural α-MSH.
Octreotide
Octreotide is a cyclic octapeptide that selectively binds somatostatin-receptor subtypes SSTR2 and SSTR5. Via G-protein-coupled signalling, adenylyl cyclase is inhibited, reducing the secretion of multiple hormones (growth hormone, IGF-1, glucagon, insulin, VIP, serotonin). Structural stabilisation via a disulfide bridge and D-amino acids extends the half-life relative to natural somatostatin (minutes to several hours).
Evidence base
Highest evidence
Human trial
Human RCT
Studies
5
5
of which in humans
5
4
Effects recorded
4
3
Open conflicts
0
0
Documented adverse events
3
2