These experiments were designed to test the effect of procaine injection into the paraventricular nucleus on the sympathetic and thermogenic changes induced by frontal cortex stimulation. Oxygen ...consumption, firing rate of the sympathetic nerves to interscapular brown adipose tissue (IBAT), along with IBAT and colonic temperatures (T
IBAT and T
C) were monitored in fasted male Sprague-Dawley rats before and 25 min after an electrical stimulation of the frontal cortex. The same variables were monitored in rats with administration of procaine into the paraventricular nucleus. The results show that cortical stimulation raises oxygen consumption, sympathetic neuron firing rates, T
IBAT, and T
C. This increase is reduced by procaine injection. These findings suggest that the paraventricular nucleus plays a key role in the sympathetic and thermogenic changes induced by cortical stimulation.
Aims: 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.
Conclusion: The thiamine‐free diet modifies the release of excitatory amino acids in the nucleus accumbens of conditioned animals. This diet also affects thermogenesis.
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