pubmed:abstractText |
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.
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