Motivation for sucrose in sated rats is predicted by low anxiety-like behavior.
Anxiety has been implicated in obesity and in the overconsumption of highly palatable foods such as those high in fat, sugar, or both. Also, the novelty-seeking trait has been associated with failure in weight-loss programs. The aim of this study was to investigate the associations of experimental anxiety and the self-administration of sucrose and high fat pellets in non-food deprived rats across different operant schedules. Male Wistar rats were subjected to the elevated plus-maze test (EPM) of anxiety-like behavior. The rats were tested for fixed ratio 5 (FR5) and progressive ratio (PR) operant responding for 50% sucrose, 95% sucrose, and high-fat pellets. PR active lever press response for 95% sucrose, but not the other pellet types, was correlated to % time spent on open arms (P=0.019) in the EPM. On the FR5 schedule, activity (closed arm entries) was correlated to the self-administration of 50% sucrose (P=0.027) and high-fat (P=0.002). This indicates an association of novelty-induced activity and self-administration of palatable food in sated rats, as well as a specific association of PR lever press response for 95% sucrose and low anxiety-like behavior. It has been argued that such active lever press response on PR may be interpreted as craving for the reinforcer; thus, our findings indicate an inverse relationship of experimental anxiety and craving for sucrose. This connection may have implications for human situations, since anxiety and novelty-seeking have been associated with obesity and failure in weight-loss programs.
Department of Neuroscience, Functional Pharmacology, Uppsala University, BMC, Box 593, 751 24 Uppsala, Sweden.
Johan
J
Alsiö
Chris
C
Pickering
Erika
E
Roman
Anna-Lena
AL
Hulting
Jonas
J
Lindblom
Helgi B
HB
Schiöth
D000818:Animals; D001007:Anxiety / Q000523:psychology*; D005247:Feeding Behavior / Q000523:psychology*; D008297:Male; D009042:Motivation; D051381:Rats; D017208:Rats, Wistar; D012528:Satiety Response / Q000502:physiology*; D013395:Sucrose
D013395:Sucrose