Acetate and arachidonate incorporations into lipids of ovine chorioallantoic tissue at day 24 of pregnancy

• Published in: Biology of reproduction Vol. 40; no. 4; pp. 785 - 791
• Main Authors: Waterman, R.A. (Beltsville Agricultural Research Center, ARS, USDA, Beltsville, MD), Lewis, G.S
• Format: Journal Article
• Language: English
• Published: Madison, WI Society for the Study of Reproduction 01.04.1989
• Subjects: ACETATE; ACETATES; Acetates - metabolism; ACETATOS; Acetic Acid; ACIDE GRAS; ACIDOS GRASOS; Allantois - metabolism; Animals; Arachidonic Acid; Arachidonic Acids - metabolism; Biological and medical sciences; BREBIS; Cholesterol Esters - metabolism; Chorion - metabolism; Esterification; EWES; Extraembryonic Membranes - metabolism; FATTY ACIDS; Fatty Acids - metabolism; Female; FETO; FOETUS; Fundamental and applied biological sciences. Psychology; GESTACION; GESTATION; Hormone metabolism and regulation; Kinetics; Lipid Metabolism; LIPIDE; LIPIDOS; LIPIDS; Lipoxygenase - metabolism; OVEJA; Phospholipids - metabolism; PREGNANCY; Pregnancy, Animal - metabolism; Pregnancy. Parturition. Lactation; Prostaglandin-Endoperoxide Synthases - metabolism; Sheep; Triglycerides - metabolism; Vertebrates: reproduction; Pregnancy; Vertebrata; Reproduction; Mammalia; Chorioallantoic membrane; Sheep; Artiodactyla; Acetate; Arachidonic acid; Metabolism; Fatty acids; Ungulata
• ISSN: 0006-3363; 1529-7268
• DOI: 10.1095/biolreprod40.4.785

Incorporation of acetate and arachidonic acid into lipid classes was examined in chorioallantoic membranes obtained from sheep at Day 24 of pregnancy. Conceptus tissues were incubated in vitro with 5 mM acetate, 0.042 mM arachidonate, 0.45 muCi [1-14C]acetate, and 5.0 muCi [5,6,8,9,11,12,14,15-3H]arachidonate for 3 and 6 h. After incubation, tissue lipid fractions were extracted, isolated, and examined for radiolabel incorporations. Medium was extracted and analyzed for radiolabeled metabolites. Metabolic pathways commonly associated with fatty acid metabolism were confirmed to be present. Acetate was utilized for de novo synthesis of free cholesterol and free fatty acid. Fatty acids containing radiolabel from both acetate and arachidonate were mainly esterified in phospholipid and triglyceride, major lipid classes found in chorioallantoic tissue. Labeled metabolites of acetate were not sufficient for analytical measurement in medium. Metabolites of arachidonic acid from lipoxygenase and cyclooxygenase pathways were determined in medium after incubation. Results suggest that, within Day 24 ovine chorioallantoic tissue, utilization of exogenous arachidonate and de novo lipogenesis from acetate function in a parallel and anabolic mode appropriate for membrane expansion.