Feeding behavior and glycemic profile in two lines of rats with genetic diabetes.

Abstract

Introduction. Food intake can aggravate diabetes in humans and in animal models. In rat model systems, the eSMT rat strain shows increased diabetes expression and higher biomass than its eSS parental line. OBVJECTIVE: The feeding behavior of eSMT and eSS males was compared under conditions of ad libitum versus restrictive food intake. The effects on rat weight and glycemia were examined.
Materials And Methods. Unrestricted food intake during growth and maintenance stages was recorded. One group of eSMT was submitted to intermittent dietary restriction for 5 weeks after weaning, followed by ad libitum food availability. A second group was restricted until one year of age. Weights and glycemic profiles were measured at periodic intervals.
Results. During the growth stage, eSMT showed weight increases higher than the eSS with similar food intake. In the maintenance stage, eSMT reached higher biomass with less intake. Post-weaning alternate restriction induced a slower growth pattern and lower adult weight. After five months of fasting, glycemia was normal (85 +/- 12 mg/dl) and controls showed altered values (119 +/- 14 mg/dl). Ad libitum nutrition after restriction resulted in glycemia levels compatible with diabetes (163 +/- 25 mg/dl) and a weight gain 75% higher than in ad libitum-fed animals.
Conclusions. Prolonged hunger-satiety alternation induced slowing of the eSMT metabolopathy, whereas refeeding was associated with higher increases of weight and glycemia. This was imputed to an augmented conversion efficiency caused by fasting. These results emphasize the importance of understanding the relations between growth, feeding and diabetes.