AMK is an active metabolite of the neurohormone melatonin .^1,2,3,4It is formed from melatoninviathe metabolic intermediate AFMK that is then deformylated by catalase or formamidase.^5,6AMK scavenges singlet oxygenin vitrowhen used at a concentration of 200 µM.¹It inhibits the epinephrine- and arachidonic acid-induced production of prostaglandin E₂and PGD₂in ovine seminal vesicle microsomes in a concentration- and time-dependent manner, as well as LPS-induced increases in COX-2 levels in RAW 264.7 macrophages when used at a concentration of 500 µM.^2,3AMK (20 mg/kg) decreases MPTP-induced increases in lipid peroxidation in the cytosol and mitochondria from substantia nigra and striatum in a mouse model of MPTP-induced Parkinson’s disease.⁴

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