title: The association of thromboxane A2 receptor with lipid rafts is a determinant for platelet functional responses.
abstract: We have investigated the presence of thromboxane A2 (TXA2) receptor associated with lipid rafts in human platelets and the regulation of platelet function in response to TXA2 receptor agonists when lipid rafts are disrupted by cholesterol extraction. Platelet aggregation with TXA2 analogs U46619 and IBOP was almost blunted in cholesterol-depleted platelets, as well as αIIbβ3 integrin activation and P-selectin exposure. Raft disruption also inhibited TXA2-induced cytosolic calcium increase and nucleotide release, ruling out an implication of P2Y12 receptor. An important proportion of TXA2 receptor (40%) was colocalized at lipid rafts. The presence of the TXA2 receptor associated with lipid rafts in platelets is important for functional platelet responses to TXA2.
authors.affiliation: IIS La Fe, University Hospital La Fe, Valencia, Spain. Electronic address: moscardo_ant@gva.es.
authors.forename: A
authors.initials: A
authors.lastname: Moscardó
authors.affiliation: Research Center, University Hospital La Fe, Valencia, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Vallés
authors.affiliation: IIS La Fe, University Hospital La Fe, Valencia, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Latorre
authors.affiliation: Research Center, University Hospital La Fe, Valencia, Spain.
authors.forename: M T
authors.initials: MT
authors.lastname: Santos
mesh_terms: D001792:Blood Platelets / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D002118:Calcium / Q000378:metabolism; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D021962:Membrane Microdomains / Q000187:drug effects / Q000378:metabolism*; D015539:Platelet Activation / Q000187:drug effects; D044244:Receptors, Thromboxane A2, Prostaglandin H2 / Q000378:metabolism*; D013928:Thromboxane A2 / Q000494:pharmacology
chemical_list: D044244:Receptors, Thromboxane A2, Prostaglandin H2; D013928:Thromboxane A2; D002118:Calcium
keywords: Lipid raft; Platelet; Signal transduction; Thromboxane A(2); Thromboxane receptor