Feeding responses of riboflavin-deficient rats to energy dilution, cold exposure and glucoprivation.

Feeding in response to various stimuli, was investigated in riboflavin-deficient rats. The animals failed to increase their food intake when fed energy-diluted diets with cellulose contents of either 15 or 30%. Furthermore, they lost reactivity to the hyperphagic action of either insulin of 2-deoxy-D-glucose regardless of a perfect response in blood glucose. Cold exposure (10 degrees), however, stimulated energy intake of the deficient rats to the same extent as that of the riboflavin-supplemented normal rats. These findings indicate that there was an operative thermostatic, but not a glucostatic control in regulation of energy intake of the riboflavin-deficient rats.