Effects of food restriction imposed to adult rats on the bone growth and the histological structure of the thyroid in their youth

Study purpose. - Our objective was the study of the development and the maturation of pups whose mothers were subjected to intermittent fasting. Materials and methods. - Eight pregnant female Wistar rats were distributed into two groups of four adult females. The rats of the first group were subjected to intermittent fasting beginning on the 14th day of gestation and continued 21 days after parturition. The rats of the second group were normally fed. The young of both groups of rats were sacrificed at the age of 21 days. Results. - The pups of the female rats submitted to food restriction showed a reduction of the body weight (-35%), of the thyroid iodine content (P < 0.001) and of segment thyroxin (P < 0.05). The histological study revealed that these pups presented colloid depletion of this follicular thyroid, non-anastomosing trabeculae, cortical bone thinning, decreased bone mineral content, absence of osteoid formation and decreased number of osteoclasts. Conclusion. - Dietary restriction imposed on adult rats, from gestation, led to the installation in their pups of a state of malnutrition and a description of thyroid histology. This thyroid abnormality is associated with hypothyroidism that led, at least in part, to the collapse of the ability to regulate bone remodeling. (C) 2011 Published by Elsevier Masson SAS.