Platelet Phosphatides. Their Fatty Acid and Aldehyde Composition and Activity in Different Clotting Systems*
Year: 1962
Type: article
Abstract: Previous studies from this laboratory revealed that phosphatidyl serine (PS) isolated from plate- let phospholipid extracts by silicic-acid column chromatography could replace blood platelets in tests of thromboplastin generation and prothrombin consumption of platelet-poor "native" plasma (1, 2).When rigorous criteria of identification were employed, it was found that phosphatidyl ethanolamine (PE) fractions contained traces of PS (2); coagulant properties were therefore difficult to evaluate.Rouser, O'Brien, and Heller (3) recently accomplished the complete separa- tion of PE from PS by means of a double column technique using silicic acid and ammoniated silicic acid.Their studies were carried out on lipids of beef brain, but the methods could be applied to human brain and platelet extracts.In 1961, an earlier study of the fatty acids of platelet phosphatides with gas-liquid chromatog- raphy was reported (4).PE and PS were then, of necessity, studied as a combined fraction, and similarly the choline phosphatides were not ade- quately separated.In addition, the significance of oxidative changes consequent to prolonged separations and exposure of phospholipids to air was not appreciated, a factor which influenced the over-all results.Zilversmit, Marcus, and Ullman (5) reported that 16 per cent (dry weight) of total platelet lipid extracts were in the plasmalogen form (phospholipids that liberate higher fatty aldehydes on hydrolysis).It could not, however, be determined how the plasmalogen was distributed among indi- vidual phosphoglycerides, although it was known (2) that the b)ulk of plasmalogen was associated * Investigation supported by a grant from the New York Heart Association.Presented in part at the meet-
DOI: 10.1172/jci104679
Language: English
Subfield: Hematology
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W2014433705