Opioid systems and feeding in the slug, Limax maximus: similarities to and implications for mammalian feeding

Substantial evidence is accumulating to implicate opioid systems in the regulation of behavioral and physiological functions in invertebrates in a manner analogous to that observed in vertebrates. This communication reviews opiate involvement in the mediation of the ingestive behaviors of the terrestrial slug, Limax maximus. The similarities to and implications for opioid modulation of mammalian feeding are considered.