Introduction: Thyroid hormones have major effects on regulation of metabolism and function of most cells. A number of prevalent diseases during adulthood have been attributed to the intrauterine status during fetal life. In this study, the effect of fetal hypothyroidism on the carbohydrate metabolism during adulthood investigated.
Subject and methods: After mating, the pregnant rats were divided in two, the fetal hypothyroidism (FH) and the control (C) groups. During the gestation period propylthiouracil (PTU) dissolved in drinking water (100 ppm) was administered to the FH group, while the C group consumed tap water. After delivery, the weight of male neonates was measured periodically until the adulthood; adult animals were anesthetized and intravenous glucose tolerance tests (IVGTT) were performed, for which catheters were inserted into the femoral vein and artery and after obtaining the first arterial sample of zero, the glucose solution (0.5 g/kg) was injected and samples were obtained 5, 10, 15, 20, 30 and 60 min. Plasma glucose and insulin concentration were measured using the glucose oxidase and ELISA methods respectively.
Results: Plasma glucose concentration at 5 min after glucose administration in the FH group (239.2±15.6 mg/dl) was significantly higher (P<0.05) than the C group (190.1±4.5 mg/dl). There was no significant difference in plasma insulin concentration of the groups. Daily water consumption during the gestational period in PTU administered mothers was significantly lower compared to the C group (P<0.05). The body weight of animals throughout the study period was significantly (P<0.05) lower in the FH group compared with the C group.
Conclusions: Fetal hypothyroidism can alter carbohydrate metabolism during adulthood, which may contribute to the diabetes development.