Transfer of 2H atoms to molecular species of ether analogues of hepatic phosphatidylcholines and phosphatidylethanolamines during metabolism of [l,l-2H2]ethanol in rats.

Rats were given [1,1-2H2]ethanol once every hour for 3-48 h and the concentrations of and deuterium incorporation into individual molecular species of either analogues of phosphatidylcholines and phosphatidylethanolamines were determined. The concentration of 1-alkyl-2-acyl-sn-glycero-3-phosphocholines increased 50-100%. The total amount of 1-alk-1'enyl-2-acyl-sn-glycero-3-phosphocholines was relatively constant but the percentage of 1-hexadec-1'-enyl-2-palmitoyl-sn-glycero-3-phosphocholine decreased throughout the experiment. A small increase of 1-alk-1'-enyl-2-sn-glycero-3-phosphoethanolamines was observed. The total deuterium content at C-2 and C-3 of the glycerol moiety of 1-alkyl-2-acyl- and 1-alk-1'-enyl-2-acyl-sn-glycero-3-phosphocholines was 2.7-4.4 atom% and 0.3-0.8 atom%, respectively, after 48 h of [1,1-2H2]ethanol administration. The corresponding values for 1-alk-1'-enyl-2-acyl-sn-glycero-3-phosphoethanolamines were 1.2-2.9 atom%. The deuterium content at C-1 of the alkyl group of 1-alkyl-2-acyl-sn-glycero-3-phosphocholines was low. The results are compatible with formation of ether lipids from alkyl dihydroxyacetone phosphate followed by reduction with NADPH with low labelling, but argue strongly against participation of alcohol dehydrogenase in the formation of the fatty alcohol.