Studies on the formation of phosphoenolpyruvate and citric acid cycle intermediates by neonatal piglet liver mitochondria.

The capacity of mitochondria isolated from livers of 5-day-old piglets to convert pyruvate to phosphoenolpyruvate, malate and citrate has been investigated. These mitochondria have a large capacity to flux pyruvate through the pyruvate carboxylase reaction causing an accumulation of malate, citrate and phosphoenolpyruvate. As much as 70% of the pyruvate utilized during state 3 respiration can flux through the pyruvate carboxylase reaction. The data indicate that phosphoenolpyruvate from mitochondria can contribute a significant fraction of the carbon skeletons of pyruvate converted to glucose by piglet liver (estimated to be 30%).

Effects of asphyxia on cardiac output and organ blood flow in the newborn piglet.

Experiments were performed on newborn piglets 6--96 hr of age. When the respiratory dead space was increased arterial pO2 decreased and pCO2 increased. During this time cardiac output was unchanged (Fig. 1), while heart rate, respiratory rate, and blood pressure increased (Figs. 2 and 3). After 90 min of asphyxia blood flow to the stomach and small and large intestines decreased. Changes in blood flow were associated with dilatation of segments of the small and large intestine with scattered areas of hemorrhage. Pathologic examination revealed scattered areas of mucosal necrosis (Fig. 6).

Death of an infant: parental grieving and the failure of social support.

Parents undergo intense grief reactions following the death of their newborn infant, but frequently fail to receive emotional support from their family and circle of friends. Because this response from family and friends differs from what occurs with the death of an older child or adult, this study was undertaken to explore the events and personal interactions that helped or hindered the parents following their infant's death. Alternations in familial and extrafamilial relationships are described in seven families with infant deaths, and useful support mechanisms are proposed.

Glucagon stimulation of hepatic gluconeogenesis in neonatal pigs.

The effect of an infusion of glucagon on gluconeogenesis was studied in 5-day-old piglets. Glucagon stimulated hepatic new glucose formation from lactate, but did not significantly change blood glucose or plasma free fatty acid levels. The data suggest that glucagon enhances substrate flow in the gluconeogenic pathway in neonatal animals.