Dissociation of place preference and tolerance responses to sucrose using a dopamine antagonist in the planarian

• Published in: Psychopharmacology Vol. 235; no. 3; pp. 829 - 836
• Main Authors: Mohammed Jawad, Rafat A., Hutchinson, Claire V., Prados, Jose
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.03.2018; Springer; Springer Nature B.V
• Subjects: Animals; Antagonist drugs; Behavior; Behavior, Addictive; Behavioral assessment; Benzazepines - pharmacology; Biomedical and Life Sciences; Biomedicine; Cocaine; Cocaine - pharmacology; Conditioning; Conditioning (Psychology); Conditioning, Classical - drug effects; Cues; Disease Models, Animal; Dopamine; Dopamine Antagonists - pharmacology; Dopamine D1 receptors; Drug abuse; Drug tolerance; Drug Tolerance - physiology; Flatworms; Male; Methods; Narcotics; Neurosciences; Original Investigation; Pharmacology/Toxicology; Physiological aspects; Place preference conditioning; Planarians - drug effects; Psychiatry; Psychopharmacology; Reinforcement; Reward; Rodents; Sucrose; Sucrose - pharmacology; Sugar; Tolerance; Planarian; Conditioned place preference; Sucrose addiction; Dopamine reward system
• ISSN: 0033-3158; 1432-2072
• DOI: 10.1007/s00213-017-4801-8

In rodents, sucrose has been found to elicit addictive-like behaviours like the development of tolerance and the association with cues present at the time of consumption. Furthermore, the neurochemical response to sucrose binges is equivalent to the one observed in response to the abuse of addictive substances like cocaine. The experiments reported here address the effects of sucrose on an invertebrate model, the Platyhelminth brown planarian. The animals exposed to a 10% sucrose solution in one context developed a conditioned place preference (CPP) which was subsequently extinguished in the absence of the rewarding agent. However, one exposure to sucrose per se sufficed to reinstate the CPP response, suggesting sucrose-induced CPP can be characterised as a standard Pavlovian response. The same training procedure led to the development of context-specific tolerance to the effects of sucrose. However, comparing animals treated with dopamine D1 antagonist (SCH-23390) with control animals showed that the establishment of CPP, but not the development of tolerance, is mediated by the dopamine reward system.