Melanotan II Lowers Body Temperature in Mice by Activating Mast Cells

Melanotan II (MTII) is a synthetic melanocortin receptor agonist primarily known for its tanning effects and sometimes explored for other indications like sexual dysfunction. While its primary actions are on melanocortin receptors, it is also associated with various side effects, including nausea and flushing. The precise mechanisms behind some of its less understood physiological effects, such as changes in body temperature, have not been fully elucidated. This study aimed to uncover the cellular and molecular pathways through which Melanotan II induces hypothermia (lowered body temperature).