Preferential hepatic galactose uptake in the newborn

Abstract

Previous studies demonstrated impaired carbohydrate tolerance with a delayed and excessive rise in plasma glucose and insulin following oral glucose in healthy full term newborns less than 24 hours of age. To evaluate the role of the liver in determining carbohydrate tolerance, galactose tolerance tests were carried out in 6 full term infants of comparable age. following a 3 hour fast, galactose (2 gr/kg) was given by gavage. Blood samples were obtained from umbilical vein and from heel sites before and half-hourly to 3 hours following galactose feeding. Results indicate a rapid rise in total sugar and glucose with an early peak following the galactose feeding with little change in insulin concentration in either umbilical or capillary blood. Paired data analysis revealed a significant difference between total sugar and glucose in umbilical venous blood which was absent in capillary blood. Similarly there was a significant difference between umbilical venous and capillary blood total sugar but no difference in glucose. The data indicate rapid hepatic uptake of galactose as opposed to glucose without change in circulating insulin. The concomitant rise in glucose suggests almost immediate conversion of galactose to glucose in the newborn, which is not seen in older children.