Muscarinic cholinergic receptor blockade in the rat prelimbic cortex impairs the social transmission of food preference

• Published in: Neurobiology of learning and memory 2007-05, Vol.87 (4), p.659-668
• Main Authors: Boix-Trelis, Núria, Vale-Martínez, Anna, Guillazo-Blanch, Gemma, Martí-Nicolovius, Margarita
• Format: Article
• Language: English
• Subjects: Acetylcholine; Analysis of Variance; Animals; Association Learning - drug effects; Association Learning - physiology; Attention; Behavioral flexibility; Behavioral psychophysiology; Biological and medical sciences; Biology; Food; Food Preferences - physiology; Food Preferences - psychology; Fundamental and applied biological sciences. Psychology; Imitative Behavior - drug effects; Imitative Behavior - physiology; Learning; Male; Medial prefrontal cortex; Memory; Muscarinic Antagonists - pharmacology; Neurosciences; Neurotransmitters; Olfactory task; Prefrontal Cortex - drug effects; Prefrontal Cortex - metabolism; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Rats; Rats, Wistar; Relational memory; Retention (Psychology) - drug effects; Retention (Psychology) - physiology; Rodents; Scopolamine; Scopolamine Hydrobromide - pharmacology; Smell; Smell - physiology; Social Environment; Social learning; Statistics, Nonparametric
• ISSN: 1074-7427; 1095-9564
• DOI: 10.1016/j.nlm.2006.12.003

Previous findings demonstrate the involvement of the cholinergic NBM in the acquisition of the social transmission of food preference (STFP), a relational associative odor-guided learning task. There is also evidence that muscarinic receptors in the medial prefrontal cortex, an important NBM target area, may modulate olfactory associative memory. The present experiment determined the consequences of blocking muscarinic cholinergic receptors in a component of the medial prefrontal region (the prelimbic cortex) on the STFP task. Adult male Wistar rats were bilaterally infused with scopolamine (20 μg/site) prior to training and showed a severe impairment in the expression of the task measured in two retention sessions, both immediately and 24 h after training. Local scopolamine injections in the prelimbic cortex did not affect other behavioral measures such as olfactory perception, social interaction, motivation to eat, neophobia, or exploration. Results suggest that muscarinic transmission in the prelimbic cortex is essential for the STFP, supporting the hypothesis that ACh in a specific prefrontal area is important for this naturalistic form of olfactory relational memory. Current data are discussed in the context of disruption of learning as a result of interferences in PLC functions such as behavioral flexibility, attention, and strategic planning.