The neonatal guinea pig as a model for human galactose metabolism: galactose-1-phosphate uridyltransferase activity

The specific activity of galactose-1-phosphate uridyltransferase was measured in fetal and neonatal guinea pig liver during the first 10 days of age. Activity was approximately six times greater than in adult animals, and peaked during the first 48 h after birth. Activity dropped sharply during the next 2 days, followed by a gradual decline. Liver galactose and glycogen levels were stable throughout the study period. Liver glucose rose significantly after birth, then dropped slightly. The pattern of uridyltransferase in the guinea pig is similar to that reported for phosphoenolpyruvate carboxylkinase and pyruvate carboxylase. Compared to the rat, specific activity of uridyltransferase peaked earlier, possibly due to the guinea pig's advanced maturity.