The production of phosphatidylinositol trisphosphate is stimulated by thrombin in human platelets.
Untreated human platelets labeled to equilibrium with 32Pi contained undetectable levels of 3-phosphorylated phosphoinositides. Stimulation of platelets with thrombin for 5 min resulted in an enormous increase in the amount of phosphatidylinositol 3,4-bisphosphate (Nolan and Lapetina, J. Biol. Chem. 265, 2441-2445; 1990). We now report that the levels of phosphatidylinositol 3,4,5-trisphosphate are greatly elevated within 90 s of treatment of platelets with thrombin. Phosphatidylinositol 3,4,5-phosphate might have an important role in platelet aggregation.
Nolan
R D
RD
Division of Cell Biology, Burroughs Wellcome Co., Research Triangle Park, NC 27709.
Lapetina
E G
EG
D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007295:Inositol Phosphates / Q000097:blood* / Q000302:isolation & purification; D007700:Kinetics; D010710:Phosphates / Q000097:blood; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols / Q000096:biosynthesis / Q000097:blood* / Q000302:isolation & purification; D010761:Phosphorus Radioisotopes; D011865:Radioisotope Dilution Technique; D013917:Thrombin / Q000494:pharmacology*
D007295:Inositol Phosphates; D010710:Phosphates; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols; D010761:Phosphorus Radioisotopes; C060974:phosphatidylinositol 3,4,5-triphosphate; D013917:Thrombin