RESUMO
Maternal obesity increases the risk of obesity in the offspring, and obesity is accompanied by an increase in blood leptin levels. Leptin can influence the progeny metabolism via its influence on fetal growth and, possibly, via its action on AgRP expression in placenta. The "yellow" mutation at the mouse agouti locus (A(y)) evokes obesity and increases blood leptin levels in pregnant mice. The aim was to examine the influence of A(y) mutation in pregnant mice on fetal weight, placental expression of AgRP gene and food intake and obesity development in progeny. A(y) pregnant females as compared to control ones had increased circulating leptin levels on days 13 and 18 of pregnancy. Both fetal weight and placental expression of AgRP gene were increased on day 13 of pregnancy and decreased on day 18 of pregnancy in A(y) females as compared to control ones. Both control (a/a) and obesity prone (A(y)/a) male young born to A(y) mothers had lowered body weight and enhanced food intake between 5 and 11 weeks of age as compared to male progeny of control mothers. The enhanced leptin levels during pregnancy in mice are associated with retardation of obesity development in obesity prone male offspring and with changes in fetal weight and AgRP gene expression in placenta.