Metabolic Responses to Physiologic Stimuli in the Newborn

Abstract

In order to evaluate the physiological adaptations to feeding in low birth weight for gestation infants and the infants or gestational diabetic mothers (IGDM), blood glucose (G), plasma insulin (PI) and free fatty acid (FFA) responses to the ingestion of formula by 42 normal newborns were studied in the first three days of life. Thses measurements were made at fasting, and 30 and 60 min after feeding. Blood glucose values rose significantly over fasting at 30 min on all 3 days, and the values at 30 min on day 3 were significantly higher than those on day 1. The only significant change in the FFA values was a lower fasting value on day 3 than on day 2. Fasting PI values on day 1 were significantly higher than those on day 3. The decrease in PI values and relatively stable FFA values after formula feeding are in contrast to changes that occur with the administration of a large quantity of glucose either orally or intravenously. This differences in metabolic homeostasis was apparent not only in the normal infant but in the IGDM and low birth weight for gestation infants as well.