title: Vigorous exercise acutely changes platelet and B-lymphocyte CD39 expression.
abstract: CD39/ATP diphosphohydrolase is expressed on B lymphocytes, cytotoxic T lymphocytes, monocytes, platelets, and endothelial cells, and it has a critical role in the inhibition of platelet responsiveness. To determine whether strenuous exercise could acutely change expression of CD39 in platelets and lymphocytes, eight healthy sedentary men, 34 yr old (SD 7), and eight physically active men, 34 yr old (SD 6), performed graded upright cycle ergometry to volitional exhaustion. Blood samples collected both at baseline and after exercise test were employed to measure CD39 expression in platelets and lymphocytes. The percentage of circulating platelet-platelet aggregates, the "in vitro" ADP and collagen-induced platelet aggregation, and the expression of both platelet glycoprotein IIb-IIIa (PAC-1) and P-selectin (CD62) were also considered markers of platelet activation. After strenuous exercise, all subjects demonstrated significant platelet activation as judged by the increased percentage of platelet-platelet aggregates. The in vitro ADP-induced platelet aggregation and the expression of CD62P on ADP-stimulated platelets significantly increased in sedentary but not in active subjects. After exercise, all of the subjects showed a significant reduction of CD39 expression in platelet [sedentary: from 2.2 (SD 0.8) to 1.1% (SD 0.8), P = 0.008; active: from 0.6 (SD 0.2) to 0.35% (SD 0.1), P = 0.009] and an increase of CD39 expression in B lymphocytes [sedentary: from 47 (SD 13) to 60% (SD 11), P = 0.0039; active: from 46 (SD 11) to 59% (SD 11), P = 0.0038]. Taken together, these findings confirm the critical role of this ADPase in inhibition of platelet responsiveness, also suggesting a possible role of B lymphocytes in thromboregulation mechanism.
authors.affiliation: Divisione di Astanteria Medica e Geriatria, Policlinico Universitario, Piazza Miraglia 2, 80138 Napoli, Italy. ludovico.coppola@unina2.it
authors.forename: Antonino
authors.initials: A
authors.lastname: Coppola
authors.forename: Ludovico
authors.initials: L
authors.lastname: Coppola
authors.forename: Liliana
authors.initials: L
authors.lastname: dalla Mora
authors.forename: Francesco M
authors.initials: FM
authors.lastname: Limongelli
authors.forename: Antonio
authors.initials: A
authors.lastname: Grassia
authors.forename: Luigia
authors.initials: L
authors.lastname: Mastrolorenzo
authors.forename: Giorgio
authors.initials: G
authors.lastname: Gombos
authors.forename: Giacomo
authors.initials: G
authors.lastname: Lucivero
mesh_terms: D000251:Adenosine Triphosphatases / Q000097:blood*; D000328:Adult; D015703:Antigens, CD / Q000097:blood*; D001081:Apyrase; D001402:B-Lymphocytes / Q000378:metabolism*; D001792:Blood Platelets / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000502:physiology*; D006801:Humans; D008297:Male; D010807:Physical Endurance / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology*; D010809:Physical Fitness / Q000502:physiology*
chemical_list: D015703:Antigens, CD; D000251:Adenosine Triphosphatases; D001081:Apyrase; C067869:CD39 antigen