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Updated: Aug 17, 2026

Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
Discovery that a melanocortin regulates sexual functions in male and female humans
1Department of Cell Biology & Anatomy, University of Arizona, College of Medicine, Tucson, AZ 85724-5044, USA. erectide@aol.com
Abstract:
Melanocortins (MCs) are multifunctional peptide hormones that regulate a diversity of physiological functions. MCs have been implicated in sexual function in animals. We document here that a MC analog, Melanotan II (MTII), can enhance sexual function in human males (erectile activity) and females (increased levels of sexual desire and genital arousal). Unlike other sexual-enhancement drugs, MTII works at the level of the brain, thus eliciting a rather natural sexual response with minimal or no undesirable side effects. The actions of the peptide were discovered accidentally while studying the effects of the peptide and related analogs on human skin pigmentation (tanning).
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