Numerous melanocortin, MCH and melatonin receptors have been identified in fish and frogs, including a homologue of MC1R, a melanocortin receptor known to regulate skin and hair colour in humans.
Identificáronse numerosos receptores de melanocortina, MCH e melatonina nos peixes e ras, incluíndo un homólogo do MC1R, un receptor da melanocortina que regula a cor do pelo e da pel nos humanos.