Fatty acid biosynthesis in sheep placenta and maternal and fetal adipose tissue

The rates of fatty acid synthesis from 3H2O and [1-14C]-acetate as substrates have been determined in sheep placental tissue and maternal and fetal adipose tissues in vitro. The tissue was obtained from sheep approximately 28 or 3 days from parturition. Placental tissue synthesised fatty acids at an appreciable rate and newly synthesised fatty acids were apparently transferred from the tissue to the incubation medium. When the results were expressed per unit of tissue weight, fetal adipose tissue synthesised fatty acids much more rapidly than did placental tissue but because there was much more of the latter tissue, the total amounts of fatty acids synthesised by each were comparable. However, it appeared that most of the fatty acids (approximately 80%) in the fetus must have been derived from the maternal plasma. The nature of the fatty acids synthesised de novo was investigated, as was the manner of their esterification.