title: Linoleic and linolenic acids are selectively secreted in triacylglycerol by hepatocytes from neonatal rats.
abstract: To determine whether specific fatty acids are metabolized differently by neonatal liver, hepatocyte cultures from neonatal (age: 5, 11, and 21 days) and adult rats were incubated with radiolabeled 18:1, 18:2, or 18:3. At each age, the rate of oxidation was highest for 18:3 and lowest for 18:1. Conversely, esterification was highest for 18:1 and lowest for 18:3. Fatty acid esterification was of the order: day 5 > day 11 > adult > day 21. When incubations contained each of two of the above fatty acids, one radiolabeled and the other not, 18:1 inhibited oxidation of radiolabeled 18:2 by up to 45% in neonatal hepatocytes. In addition, added 18:1 increased glycerolipid accumulation from 18:2 and 18:3. Under these conditions, the relative proportion of triacylglycerol secreted in the medium, compared with that accumulated in the cells, was two- to fourfold higher for day 11 and 21 rat hepatocytes. The results suggest that a specific mechanism exists in the livers of neonatal rats to spare n-3 and n-6 fatty acids from oxidation and instead secrete them in triacylglycerol.
authors.affiliation: Department of Nutrition, School of Public Health, University of North Carolina at Chapel Hill 27599-7400, USA.
authors.forename: N
authors.initials: N
authors.lastname: Emmison
authors.forename: P A
authors.initials: PA
authors.lastname: Gallagher
authors.forename: R A
authors.initials: RA
authors.lastname: Coleman
mesh_terms: D000375:Aging / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn / Q000254:growth & development / Q000378:metabolism*; D002478:Cells, Cultured; D003470:Culture Media / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D005260:Female; D019787:Linoleic Acid; D008041:Linoleic Acids / Q000378:metabolism*; D050356:Lipid Metabolism; D008099:Liver / Q000166:cytology / Q000378:metabolism*; D008297:Male; D010084:Oxidation-Reduction; D010743:Phospholipids / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D014280:Triglycerides / Q000378:metabolism*; D017962:alpha-Linolenic Acid / Q000378:metabolism*
chemical_list: D003470:Culture Media; D005227:Fatty Acids; D008041:Linoleic Acids; D010743:Phospholipids; D014280:Triglycerides; D017962:alpha-Linolenic Acid; D019787:Linoleic Acid