An aversive diet as thiamine-free food blocks food-induced release of excitatory amino acids in the accumbens.
OBJECTIVE
As the nucleus accumbens shell plays an important role in the control of eating behaviour, the aim of this study was to evaluate the changes in: (a) the level of aspartic and glutamic acids in the accumbens shell of conditioned rats after the presentation of an aversive diet containing thiamine-free food; (b) the temperature of interscapular brown adipose tissue, effector of thermogenesis related to food intake.


METHODS
The concentration of aspartic and glutamic acids in the accumbens shell, and brown adipose tissue temperature were monitored in conditioned male Sprague-Dawley rats before and after the presentation of thiamine-free food or standard laboratory food. The aspartic and glutamic acids were collected using a microdialysis probe and quantified by HPLC. Food intake was also measured.


RESULTS
The results indicated that an intake of standard laboratory food induced an increase in the level of aspartic and glutamic acids, and an elevation in temperature of brown adipose tissue; whereas an intake of thiamine-free food blocks these increases in the conditioned animals.


CONCLUSIONS
The thiamine-free diet modifies the release of excitatory amino acids in the nucleus accumbens of conditioned animals. This diet also affects thermogenesis.
Monda
M
M
Department of Experimental Medicine, Section of Human Physiology, Second University of Naples, Naples, Italy.
Viggiano
A
A
De Luca
V
V
D000273:Adipose Tissue / Q000502:physiology; D000818:Animals; D001224:Aspartic Acid / Q000032:analysis*; D001831:Body Temperature / Q000502:physiology; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004032:Diet / Q000379:methods*; D004435:Eating / Q000502:physiology; D018698:Glutamic Acid / Q000032:analysis*; D008297:Male; D009714:Nucleus Accumbens / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D022722:Thermogenesis / Q000502:physiology; D013831:Thiamine / Q000378:metabolism
D001224:Aspartic Acid; D018698:Glutamic Acid; D013831:Thiamine