Gluconeogenesis in Neonatal Piglet Liver

The gluconeogenic capacity of livers from day old and 5-day-old piglets has been studied. The data show infused piglets and perfused livers convert lactate to glucose. Studies with isolated liver mitochondria show a large capacity to flux pyruvate through the pyruvate carboxylase reaction causing an accumulation of malate, citrate and phosphoenolypyruvate. Factors that affect accumulation of malate, citrate and phosphoenolypyruvate are described. Infusion of day-old piglets with oleic acid for 3 hr did not affect parameters investigated. Experiments on the capacity of livers from 5 day old piglets to control glucose production from lactate in the presence of glucose at concentrations considered to be hypoglycemic (30 mg%) and hyperglycemic (300 mg%) indicate a lack of such control. Similar concentrations of 10 mM lactate were converted to glucose over a 3 hr period in these experiments.