Adenosine Diphosphate/metabolism; Blood Platelets/enzymology; Cell Shape; Glycogen Synthase Kinase 3/metabolism; Integrins/metabolism; Platelet Activation; Proto-Oncogene Proteins c-akt/metabolism; Signal Transduction; Animals; Blood Platelets/drug effects; Cell Shape/drug effects; Enzyme Activation; Glycogen Synthase Kinase 3/antagonists & inhibitors; Glycogen Synthase Kinase 3 beta; Humans; Mice; Mice, Inbred C57BL; Mice, Knockout; Phosphatidylinositol 3-Kinases/metabolism; Phosphorylation; Platelet Activation/drug effects; Protein Kinase Inhibitors/pharmacology; Proto-Oncogene Proteins c-akt/antagonists & inhibitors; Proto-Oncogene Proteins c-akt/deficiency; Proto-Oncogene Proteins c-akt/genetics; Purinergic P2Y Receptor Antagonists/pharmacology; Receptors, Purinergic P2Y1/drug effects; Receptors, Purinergic P2Y1/metabolism; Receptors, Purinergic P2Y12/drug effects; Receptors, Purinergic P2Y12/genetics; Receptors, Purinergic P2Y12/metabolism; Signal Transduction/drug effects; Time Factors; src-Family Kinases/metabolism