title: The metabolism of 18:0 and 18:2(n-6) by the ovine placenta at 120 and 150 days of gestation.
abstract: 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.
mesh_terms: D000818:Animals; D044943:Fatty Acid Desaturases / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000378:metabolism*; D005260:Female; D005865:Gestational Age; D050602:Linoleoyl-CoA Desaturase; D008055:Lipids / Q000096:biosynthesis*; D008431:Maternal-Fetal Exchange; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D012756:Sheep / Q000378:metabolism*; D013229:Stearic Acids / Q000378:metabolism*; D013230:Stearoyl-CoA Desaturase
chemical_list: D005231:Fatty Acids, Unsaturated; D008055:Lipids; D013229:Stearic Acids; D044943:Fatty Acid Desaturases; D013230:Stearoyl-CoA Desaturase; D050602:Linoleoyl-CoA Desaturase; C029627:delta-9 fatty acid desaturase