Lipids from human platelets in primary thrombocythemia.

Lipids in platelets of a patient with primary thrombocythemia were analyzed. Main neutral and acidic glycosphingolipids were globo-series and hematoside (GM3), respectively. In addition, galactosylceramide was found for the first time in human platelets. This glycosphingolipid contained a considerable amount of hydroxy-fatty acids. Free ceramide was found, and compared to about half the total amount of the glycosphingolipids. The ceramide moiety of sphingomyelin was slightly different from those of the glycosphingolipids. Molar ratio of cholesterol to phospholipid showed 0.71 which was higher than that in normal platelets.