Molecular species of lecithins from various animal tissues

Abstract

1. 1. The molecular species composition of lecithins from lung, brain, liver and kidney derived from rat, rabbit, pig and cow was determined. 2. 2. In all animals considerable differences were found in the molecular composition of lecithins from the various tissues. The composition of lecithins from lung and brain showed many similarities irrespective of animal species. This may indicate a certain degree of tissue specificity. On the other hand, pronounced differences were observed in the lecithin composition of liver and kidney from the different animals. 3. 3. (Dipalmitoyl)-lecithin was the main lecithin present in lung, but was only a trace compound in the liver and kidney of all animals examined. No significant amounts of (distearoyl)- or (1-palmitoyl-2-stearoyl)-lecithin could be detected in any tissues investigated. 4. 4. Lecithin species containing oleic acid were found to predominate in brain. In general, the content of (1-palmitoyl-2-oleoyl)-lecithin was higher than (1-stearoyl-2-oleoyl)-lecithin. Species with linoleic acid were not significantly present in brain. 5. 5. Lecithins containing one saturated and one polyunsaturated fatty acid constituent are abundant in the liver and kidney of all animals species examined. Molecules with two identical or two different polyunsaturated acyl constituents were not encountered in significant amounts in the tissues investigated.