Plasma free fatty acid umbilical venous-arterial concentration differences and placental transfer of [14C]palmitic acid in pigs.
The passage of plasma free fatty acids across the pig placenta was investigated in four anaesthetized sows with a total of 41 fetal piglets. The plasma free fatty acid concentrations in fetal piglets were very low and appeared independent of maternal concentrations. In each piglet there was a small positive umbilical venous-arterial concentration difference. There were large differences between the composition of maternal and fetal plasma free fatty acid. The fetal free fatty acid contained relatively large amounts of arachidonic and docosahexaenoic acids. [14C]palmitic acid given intravenously to the sows appeared rapidly in fetal plasma free fatty acids but the amount of radioactivity was low. Analysis of the specific activity of palmitic acid in fetal and maternal blood indicated that little more than 10% of fatty acids coming from the placenta were derived directly from maternal plasma free fatty acids. It is concluded that, in the anaesthetized pig at Caesarean section, fatty acids enter the fetal circulation from the placenta and are taken up by the fetus at rates exceeding the requirements for structure and storage, but the major part of these free fatty acids are not derived directly from maternal free fatty acids.
D000818:Animals; D005230:Fatty Acids, Nonesterified / Q000097:blood*; D005260:Female; D005312:Fetal Blood / Q000032:analysis*; D010169:Palmitic Acids / Q000097:blood / Q000378:metabolism; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D013552:Swine; D014469:Umbilical Arteries; D014471:Umbilical Veins
D005230:Fatty Acids, Nonesterified; D010169:Palmitic Acids