title: Evidence that adhesion of electrically permeabilized platelets to collagen is mediated by guanine nucleotide regulatory proteins.
abstract: Adhesion of electrically permeabilized platelets to collagen was found to be essentially independent of free Ca2+ concentration in the medium. Addition of stable GTP analogues increased the proportion of adhering cells about 5-fold. This effect was inhibited by guanosine 5'-[beta-thio]diphosphate, cytochalasin D or monoclonal antibodies to glycoprotein Ia. In contrast, the protein kinase C inhibitor staurosporine had only a small effect on the GTP-analogue-enhanced adhesion of the permeabilized cells to collagen. These results suggest that a guanine nucleotide regulatory (G)-protein is directly linked to the collagen receptor and is involved in the actin-dependent recruitment of additional collagen receptors.
authors.affiliation: Department of Pharmacology, Temple University Medical School, Philadelphia, PA 19140.
authors.forename: J L
authors.initials: JL
authors.lastname: Daniel
authors.forename: C
authors.initials: C
authors.lastname: Dangelmaier
authors.forename: J B
authors.initials: JB
authors.lastname: Smith
mesh_terms: D000470:Alkaloids / Q000494:pharmacology; D000911:Antibodies, Monoclonal; D001792:Blood Platelets / Q000166:cytology*; D002118:Calcium / Q000378:metabolism; D002413:Cations, Divalent; D002448:Cell Adhesion / Q000187:drug effects; D002478:Cells, Cultured; D003094:Collagen / Q000378:metabolism*; D015638:Cytochalasin D / Q000494:pharmacology; D004594:Electrophysiology; D019204:GTP-Binding Proteins / Q000502:physiology*; D006801:Humans; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D019311:Staurosporine
chemical_list: D000470:Alkaloids; D000911:Antibodies, Monoclonal; D002413:Cations, Divalent; D015638:Cytochalasin D; D003094:Collagen; D011493:Protein Kinase C; D019204:GTP-Binding Proteins; D019311:Staurosporine; D002118:Calcium