La thermogenèse induite par l'alimentation chez le rat Zucker âgé de 2 et 7 jours

Abstract

Summary. Diet-induced thermogenesis in 2 and 7-day old Zucker rats.Gas exchanges were measured at the thermoneutral temperature of 35 °C on « fasted » (3 h 30 min) and then « reted » (75 min) fa/fa and Fa/fa rats aged 2 and 7 days.The C0 2 production, 0 2 consumption and respiratory quotient increased significantly after refeeding in all pups. The percentage of increase in the gas exchanges was similar in both genotypes at 2 days. At 7 days, the percentage of increase was significantly higher in Fa/fa than in fa/fa pups. This demonstrated a defect in diet-induced thermogenesis in 7-day old pups.However, since this defect (unlike non-shivering thermogenesis) was absent in 2-day old pups, it is concluded that it is probably not a primary factor but rather a consequence of the obesity already present in fa/fa pups at 7 days of age.Introduction.