Effect of chloroquine treatment on the different phospholipid species of rat liver lysosomes.

The lysosomal phospholipids of rat liver were determined after treatment of the animals with chloroquine for varying periods up to 15 days. During this period, all the measured phospholipids increased. After two weeks of treatment the absolute level of each phospholipid had increased 3 to 6-fold, with the exception of bis(monoacylglycero)phosphate which was increased 25-fold, accounting for one third of the total phospholipids. The fatty acid pattern not only differed between the classes of lipids; it changed during treatment within every lipid class. In addition to other changes, the polyenoic fatty acids of the main glycerophospholipids were markedly reduced between the 3rd and 14th day of chloroquine treatment: to one half in phosphatidylcholine, to about one tenth in phosphatidylethanolamine, and to one quarter in phosphatidylinositol. However, the polyenoic fatty acid content of bis(monoacylglycero)phosphate was doubled, reaching 76% of the total at the end of treatment. Whereas docosahexaenoic acid was not detected in this acidic phospholipid in the first 3 days of treatment, it was present to the extent of 55% of the total fatty acids after 15 days of chloroquine application;