Generation and remodeling of highly polyunsaturated molecular species of rat hepatocyte phospholipids.
Freshly isolated rat hepatocytes were incubated for 20 min with [U-14C]glycerol in the presence or absence of unlabeled linoleic (18:2n-6), arachidonic (20:4n-6), or docosahexaenoic (22:6n-3) acid, added as albumin complex in 10% ethanol. Most of the radioactivity (approximately 95%) recovered in hepatocyte lipids was present in phosphatidylcholine (PC), phosphatidylethanolamine (PE), and triacylglycerol (TAG). The presence of exogenous fatty acids resulted in (i) higher incorporation of [U-14C]glycerol, (ii) higher percentage of label in TAG, and (iii) enhanced formation of PC and PE molecular species bearing the exogenous fatty acid at both the sn-1 and sn-2 positions of glycerol. In each case, these molecular species contained 60 to 70% of the label in that lipid class. Further incubation of the cells for 40 and 80 min in the absence of labeled substrate and exogenous fatty acids resulted in a redistribution of label among PC and PE molecular species due to deacylation-reacylation at the sn-1 position of glycerol.
Schmid
P C
PC
Hormel Institute, University of Minnesota, Austin 55912, USA. schmi081@maroon.tc.umn.edu
Spimrova
I
I
Schmid
H H
HH
D000818:Animals; D016718:Arachidonic Acid / Q000378:metabolism; D002208:Caproates / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D004075:Diglycerides / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000378:metabolism*; D005990:Glycerol / Q000378:metabolism; D019787:Linoleic Acid / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D010713:Phosphatidylcholines / Q000378:metabolism; D010714:Phosphatidylethanolamines / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014280:Triglycerides / Q000378:metabolism
D002208:Caproates; D004075:Diglycerides; D005231:Fatty Acids, Unsaturated; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010743:Phospholipids; D014280:Triglycerides; D016718:Arachidonic Acid; D019787:Linoleic Acid; D005990:Glycerol