Skin Pigmentation in Rodents – Animal models demonstrate that Melanotan II, as a non-selective agonist of melanocortin receptors (especially MC₁), promotes skin pigmentation by mimicking α‑MSH and triggering melanogenesis, leading to a darker coat in rodents.

UV Protection in Mice – Preclinical data—including work on related melanocortin receptor agonists—suggest MC₁ activation enhances melanin-mediated defense mechanisms, promotes DNA repair, and reduces UV-induced damage, implying that Melanotan II may similarly bolster natural UV protection via melanin production .

Neurological and Endocrine Activity in Rats – In rats, systemic administration of Melanotan II activated oxytocin-producing neurons in the hypothalamus (SON and PVN), increasing Fos expression and neuronal firing, indicating MT‑II engages central melanocortin pathways with downstream neuroendocrine effects