title: GTP regulation of platelet-activating factor binding to human neutrophil membranes.
abstract: Radiolabeled ligand binding studies showed that specific receptors for platelet-activating factor are present in human neutrophil membranes. GTP at 10(-7) to 10(-3) M decreased the specific binding of platelet-activating factor to neutrophil membranes in a dose-dependent manner. Inhibition of platelet-activating factor binding was also induced by other guanine nucleotides but not by adenine nucleotides. Our results suggest that platelet-activating factor receptor in human neutrophil membranes may be coupled to a guanine nucleotide binding protein.
mesh_terms: D000227:Adenine Nucleotides / Q000378:metabolism; D001667:Binding, Competitive; D002462:Cell Membrane / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000494:pharmacology*; D006801:Humans; D009504:Neutrophils / Q000378:metabolism*; D010972:Platelet Activating Factor / Q000378:metabolism*; D010980:Platelet Membrane Glycoproteins; D011956:Receptors, Cell Surface / Q000378:metabolism*; D043562:Receptors, G-Protein-Coupled
chemical_list: D000227:Adenine Nucleotides; D010972:Platelet Activating Factor; D010980:Platelet Membrane Glycoproteins; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; C039351:platelet activating factor receptor; D006160:Guanosine Triphosphate; D019204:GTP-Binding Proteins