Encoding and selective activation of "metabolic memories" in the rat.
Experiment 1 used Pavlovian conditioning procedures to show that rats formed distinct memorial representations of 2 (peanut oil and sucrose pellets) unconditioned stimuli (USs) that could be activated by 2 different conditioned stimuli (CSs). After training in Experiment 2, rats injected with the lipid antimetabolite Na-2-mercaptoacetate (MA) responded more to the CS for oil than to the CS for sucrose. This pattern was not shown by rats that received isotonic saline or systemic 2-deoxy-d-glucose (a glucose antimetabolite). By contrast, intracerebroventricular infusion of the glucose antimetabolite 5-thioglucose selectively promoted responding to the CS for sucrose (Experiment 4). Thus, lipoprivic and glucoprivic treatments selectively promoted the activation of the memories of fat and carbohydrate USs, respectively. In Experiment 3, the capacity of MA to augment responding to a CS for oil was abolished for rats that received subdiaphragmatic vagal deafferentation. This indicates that the capacity of lipoprivic signals to selectively activate the representations of fat USs may depend on vagal afferent fibers.
Davidson
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Department of Psychological Sciences, Purdue University, West Lafayette, Indiana 47907, USA. davidson@psych.purdue.edu
Altizer
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Benoit
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Walls
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Powley
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D000818:Animals; D000963:Antimetabolites / Q000494:pharmacology; D001245:Association Learning / Q000187:drug effects / Q000502:physiology; D001362:Avoidance Learning / Q000187:drug effects / Q000502:physiology; D001786:Blood Glucose / Q000378:metabolism; D001921:Brain / Q000187:drug effects / Q000502:physiology*; D003214:Conditioning, Classical / Q000187:drug effects / Q000502:physiology*; D003847:Deoxyglucose / Q000494:pharmacology; D004734:Energy Metabolism / Q000187:drug effects / Q000502:physiology*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005247:Feeding Behavior / Q000187:drug effects / Q000502:physiology*; D005518:Food Preferences / Q000187:drug effects / Q000502:physiology; D007276:Injections, Intraventricular; D008297:Male; D011939:Mental Recall / Q000187:drug effects / Q000502:physiology*; D009042:Motivation; D000074241:Peanut Oil; D010938:Plant Oils / Q000008:administration & dosage; D051381:Rats; D017207:Rats, Sprague-Dawley; D013395:Sucrose / Q000008:administration & dosage; D013649:Taste / Q000187:drug effects / Q000502:physiology; D013864:Thioglycolates / Q000494:pharmacology
D000963:Antimetabolites; D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D000074241:Peanut Oil; D010938:Plant Oils; D013864:Thioglycolates; D013395:Sucrose; C017487:2-mercaptoacetate; D003847:Deoxyglucose