Anaerobic, Glycogen-dependent Transport of Amino Acids by the Placenta

Placental Amino Acid Uptake. II. Tissue Preincubation, Fluid Distribution, and Mechanisms of Regulation

“…Amino acids are actively transported by the placenta and their concentrations are higher in fetal blood than in maternal (4, 5 , 7, 11, 24). The relatively large quantities of amino acids required for the needs of the fetus and their importance in fetal nutrition lead t o the use of i n vitro techniques for the study of placental transport mechanisms (6,16,17,23). …”

Effect of Maternal Oxygen Inhalation on the Fetus with Growth Retardation

“…By itself, however, increased maternal arterial PO2 of a magnitude similar to that observed in this study would be expected to result in an increase in placental oxygen transfer and in umbilical venous PO2 (15). Alternately, correction of placental hypoxemia could restore to normal glucose and amino acid transfer to the fetus (8,9), if substrate deficiency, rather than hypoxemia, were the direct cause of growth retardation. An additional explanation for improved fetal growth is that supplemental maternal oxygen inhalation resulted in a change in the fetal hormonal milieu.…”

Adenine Nucleotide Catabolism in the Human Trophoblast Early and Late in Gestation

“…Both used in accelerated glycolysis (2, 7). However, substantial glycoduring hypoxia (N2-atmosphere) and in the absence of genolysis takes place during hypoxia, when availability of free glucose, ATP and EC were preserved for up to 8 h. 2-glucose is limited (5,11,13). Despite the increase in ATP Deoxyglucose caused a fall in ATP to 12.1 + 5.0 and 14.8 production through anaerobic glycolysis, tissue ATP and total + 7.4% of initial levels, and in EC to 0.46 f 0.04 and 0.42 adenine nucleotides decrease under these circumstances.…”

“…and a stable carbohydrate metabolism for were similar. Of total adenine nucleotides degraded, 7.1-several hours by anaerobic glycolysis alone (2,4,5,11). When 10.5% were released extracellularly as adenosine, when its activity of glycolysis is decreased, these processes are rapidly deamination was inhibited.…”

“…When 10.5% were released extracellularly as adenosine, when its activity of glycolysis is decreased, these processes are rapidly deamination was inhibited. Human trophoblast appears to impaired (5,7). tolerate transient hypoxia or deprivation of exogenous…”