title: Platelet release products modulate some aspects of polymorphonuclear leukocyte activation.
abstract: The aim of this research was to evaluate in vitro interactions between platelets and polymorphonuclear leukocytes. The effects of supernatant from thrombin-activated platelets and two platelet release products (adenosine triphosphate and beta-thromboglobulin) were tested on the following features of polymorphonuclear leukocytes activation: opsonized zymosan and phorbol myristate acetate stimulated chemiluminescence, release of membrane bound calcium, NADPH-oxidase activity, and membrane fluidity (fluorescent polarization). The results showed that the addition of platelet supernatant to polymorphonuclear leukocytes induces a significant activation of cells. On the other hand, after three hours of preincubation of polymorphonuclear leukocytes with platelet supernatant, a decreased response of polymorphonuclear leukocytes to stimulation with phorbol myristate acetate, a significant decrease in NADPH-oxidase activity, and a lowered membrane fluidity were observed. Adenosine triphosphate modulated only opsonized zymosan stimulated chemiluminescence, with and without preincubation with polymorphonuclear leukocytes. Beta-thromboglobulin caused a decrease of the chemiluminescent response of polymorphonuclear leukocytes, using both agonists, with and without preincubation with polymorphonuclear leukocytes. Moreover beta-thromboglobulin only caused a decrease of the polymorphonuclear leukocytes membrane fluidity without preincubation with the cells. These results support the thesis that platelets have a "time-related" modulating activity on polymorphonuclear leukocytes.
authors.affiliation: Institute of Rheumatology, Faculty of Medicine, University of Ancona, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Allegrezza-Giulietti
authors.forename: R
authors.initials: R
authors.lastname: Serretti
authors.forename: E
authors.initials: E
authors.lastname: Beccerica
authors.forename: S
authors.initials: S
authors.lastname: Muti
authors.forename: G
authors.initials: G
authors.lastname: Ferretti
authors.forename: C
authors.initials: C
authors.lastname: Cervini
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D005454:Fluorescence Polarization; D006801:Humans; D008163:Luminescent Measurements; D008560:Membrane Fluidity / Q000187:drug effects / Q000502:physiology; D008566:Membranes / Q000378:metabolism; D009247:NADH, NADPH Oxidoreductases / Q000032:analysis; D019255:NADPH Oxidases; D009504:Neutrophils / Q000187:drug effects / Q000502:physiology*; D015539:Platelet Activation / Q000187:drug effects / Q000502:physiology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013917:Thrombin / Q000494:pharmacology; D015054:Zymosan / Q000494:pharmacology; D001620:beta-Thromboglobulin / Q000494:pharmacology
chemical_list: D001620:beta-Thromboglobulin; D000255:Adenosine Triphosphate; D015054:Zymosan; D009247:NADH, NADPH Oxidoreductases; D019255:NADPH Oxidases; D013917:Thrombin; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium