Shand J H, Noble R C
Lipids. 1981 Jan;16(1):68-71. doi: 10.1007/BF02534924.
The effects of approach of parturition in the sheep on the incorporation of 18:0 and 18:2(n-6) into the placenta lipids and on the activities of the delta 9- and delta 6-desaturase enzymes of placental tissue have been studied in vitro. The incorporation of 18:0 into the esterified lipids of placental tissue between the 120th and 150th days of gestation declined markedly; the high level of incorporation of 18:2(n-6) into the esterified lipids of the placenta (some 2-fold higher than 18:0) remained constant over the gestational period. While placental delta 9-desaturase activity was the same at 150 days as at 120 days of gestation, the activity of the delta 6-desaturase enzyme increased significantly. These results are discussed in relation to the fetal demand for fatty acids near term and the differences that exist between the mechanisms of maternal-fetal transfer of 18:0 and 18:2(n-6) in the sheep.
已在体外研究了绵羊分娩方式对18:0和18:2(n-6)掺入胎盘脂质以及胎盘组织中δ9-和δ6-去饱和酶活性的影响。在妊娠第120天至150天期间，18:0掺入胎盘组织酯化脂质的量显著下降；胎盘酯化脂质中18:2(n-6)的高掺入水平（比18:0高约2倍）在妊娠期保持恒定。虽然胎盘δ9-去饱和酶活性在妊娠150天时与120天时相同，但δ6-去饱和酶的活性显著增加。结合绵羊接近足月时胎儿对脂肪酸的需求以及18:0和18:2(n-6)在母胎转运机制上的差异对这些结果进行了讨论。
