Inhibition of platelet aggregation by synthetic phosphatidylcholines: possible involvement of vesiculation of platelet plasma membranes.
Synthetic phosphatidylcholines inhibited thrombin-induced aggregation of rabbit platelets. The inhibitory effect of the phosphatidylcholines increased with an increase in the chain-length of the constituent fatty acids up to 12, and then decreased, and C14:0PC and C16:0PC did not inhibit platelet aggregation. The activity of synthetic phosphatidylcholines as to induction of vesiculation of platelet plasma membranes (Kobayashi, T., Okamoto, H., Yamada, J.-I., Setaka, M. and Kwan, T. (1984) Biochim. Biophys. Acta 778, 210-218) and the inhibitory effect of these phosphatidylcholines on platelet aggregation showed the same dependence on the constituent fatty acids of the phosphatidylcholines. The amounts of phosphatidylcholines required for 50% inhibition of platelet aggregation correspond very well to those required for 15% exfoliation of acetylcholinesterase activity, suggesting that there is a close relationship between platelet aggregation and vesiculation of the platelet plasma membrane. The possible mechanism of inhibition of platelet aggregation by synthetic phosphatidylcholines is discussed.
D000110:Acetylcholinesterase / Q000097:blood; D000818:Animals; D001792:Blood Platelets / Q000166:cytology; D002462:Cell Membrane / Q000187:drug effects*; D005227:Fatty Acids / Q000032:analysis; D010713:Phosphatidylcholines / Q000494:pharmacology*; D010974:Platelet Aggregation / Q000187:drug effects; D011817:Rabbits; D012701:Serotonin / Q000097:blood; D013329:Structure-Activity Relationship; D013917:Thrombin / Q000494:pharmacology
D005227:Fatty Acids; D010713:Phosphatidylcholines; D012701:Serotonin; D000110:Acetylcholinesterase; D013917:Thrombin