Opioid-induced feeding in the slug, Limax maximus.

Administration of the opioid agonist, morphine (1 and 10 mg X kg-1), resulted in significant, dose-dependent increases in the ingestive responses of food-deprived slugs, Limax maximus, and in the initiation of feeding in satiated animals. These effects could be blocked by the opiate antagonist, naloxone (1 mg kg-1), with naloxone by itself causing a significant decrease in the feeding of food-deprived slugs. These results suggest that opiates are involved in the control of the feeding behavior of Limax.