Phosphatidylcholine breakdown in HDL3 stimulated platelets.
Low concentrations of HDL3 stimulate a transient biphasic increase in 1,2-diacylglycerol (DAG), with an early phase peaking at 30 seconds and a late phase at 60 seconds in (3H)-phosphatidylcholine prelabelled platelets. DAG generation is coupled to apolipoprotein AII or AI binding to specific surface receptors. Coincubations with HDL3 and 0.2 microM phorbol ester induced a significant rise in the second phase DAG indicating the involvement of protein kinase C in this late phase. The HDL3 induced production of DAG in platelets pretreated with 6 microM R 59022 is enhanced, while phosphatidic acid (PA) content was reduced, suggesting that DAG attenuation is derived at least in part from a pathway involving DAG-Kinase.
Nazih
H
H
Institut Pasteur, Lille, France.
Devred
D
D
Martin-Nizard
F
F
Fruchart
J C
JC
Delbart
C
C
D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D019852:Diacylglycerol Kinase; D004075:Diglycerides / Q000096:biosynthesis; D006801:Humans; D066298:In Vitro Techniques; D008075:Lipoproteins, HDL / Q000302:isolation & purification / Q000502:physiology*; D053440:Lipoproteins, HDL3; D010712:Phosphatidic Acids / Q000494:pharmacology; D010713:Phosphatidylcholines / Q000097:blood*; D010770:Phosphotransferases / Q000378:metabolism; D011493:Protein Kinase C / Q000494:pharmacology; D013110:Sphingosine / Q000494:pharmacology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
C011439:1,2-diacylglycerol; D004075:Diglycerides; D008075:Lipoproteins, HDL; D053440:Lipoproteins, HDL3; D010712:Phosphatidic Acids; D010713:Phosphatidylcholines; D010770:Phosphotransferases; D019852:Diacylglycerol Kinase; D011493:Protein Kinase C; D013110:Sphingosine; D013755:Tetradecanoylphorbol Acetate