Melanocortin Receptor Peptides

The melanocortin system runs on five receptors, MC1R through MC5R, and this class exists because a single research programme at the University of Arizona in the 1980s set out to make a stable analogue of alpha-MSH and ended up producing several. Melanotan I (afamelanotide) is the linear analogue; Melanotan II is the cyclic one, and it is more potent but far less selective across the receptor subtypes. PT-141 (bremelanotide) exists because of an unplanned observation during Melanotan II testing — effects unrelated to pigmentation — and was developed from that lead as a metabolite. Kisspeptin-10 is the outlier: it acts at GPR54, not a melanocortin receptor, and is included here because its literature sits alongside the others in neuroendocrine signalling work. All characterisation is rodent and in-vitro.

4 compounds · For Research Use Only. Not for Human Consumption.