CARBOHYDRATE METABOLISM IN PREGNANCY: THE TURNOVER OF I131-INSULIN IN THE PREGNANT RAT1

Abstract
The effects of pregnancy upon insulin metabolism have been examined in the rat. Fractional turnover of I131-insulin was measured in normal and 21-day pregnant rats as well as in animals within one to eight hours following parturition. Half-time for the disappearance of I13l-insulin from the circulation (as measured by chromatographic techniques) averaged 15.4 minutes in the pregnant group and 20.8 minutes in the non-pregnant litter mates. The significant acceleration of insulin turnover of the pregnant animals did not persist in the immediate post-partum period. The findings indicate that insulin metabolism is altered during pregnancy and that the presence of the conceptus may contribute to these changes.