Melanotan 1 is a highly potent melanotropin with extended biological activity and resistance to enzymatic degredation by serum enzymes. [Nle4, D-Phe7]-α-Melanocyte Stimulating Hormone trifluoroacetate salt has been used to detect its effect on O2 consumption and CO2 production in C57BL/6 mice. It is also used to determine its effect on leptin secretion in the primary cultures of differentiated adipocytes.