Melanotan II is an agonist of melanocortin receptor 1 (MC1R), MC3R, MC4R, and MC5R (Kis = 0.67, 34, 6.6, and 46 nM, respectively, in COS cells expressing human recombinant receptors). It improves recovery of sciatic nerve function after mechanical injury in rats, and increases cisplatin-induced decreases in sensory nerve conduction velocity when administered at a dose of 20, but not 2 or 50, µg/kg. Melanotan II (1 nmol, i.c.v.) increases oxygen consumption and protein levels of uncoupling protein 1 (UCP1) in brown adipose tissue homogenates and decreases food intake, body weight, and serum levels of leptin, glucose, insulin, and cholesterol in chow-fed and diet-induced obese rats.
