Dietary composition during fetal and neonatal life affects neuropeptide Y functioning in adult offspring

The aim of this study was to examine the impact of maternal diet during the gestation and lactation periods on the neuropeptide Y (NPY) system in adul t offspring. Male Long-Evans rats were obtained from dams fed either on a w ell-balanced diet (C), a high carbohydrate diet (HC) or a high-fat diet (HF ) and fed themselves on the well-balanced dirt for their whole lift. At 6 m onths of age, their feeding response to various doses of NPY injected in th e lateral brain ventricle was measured in one group and NPY concentrations in microdissected nuclei of the hypothalamic were measured in a second grou p. The HF rats were lighter than the two other groups (P<0.001). The contro l rats showed a typical dose-dependent feeding response to NPY. The HC rats showed a continuous increase in the response, starting at the intermediate dose (1.0 <mu>g) only while the HF rats had a maximal response at the lowe st dose (0.5 mug). The HF rats ate twice as much as the HC rats at the lowe st dose tested 1 h after injection (4.4+/-0.6 vs. 2.7+/-0.4 g; P<0.05), sho wing therefore the greatest sensitivity to NPY. This change in the sensitiv ity was not related to hypothalamic NPY concentration as it was not modifie d in the arcuate and paraventricular nuclei. The diet imposed on the mother could have long-lasting effects on body weight regulation of the offspring s and alter the NPY system likely through modifications at the receptor lev el. (C) 2000 Elsevier Science B.V. All rights reserved.