title: Supine rest reduces platelet activation and aggregation.
abstract: Platelet activation and aggregation are central processes in acute coronary syndromes and myocardial infarction, and are stimulated by physical and mental stress. However, it is not known if and to what extent the "ordinary" stress inherent in a person's daily routine contributes to platelet activation and aggregation. We measured platelet activation and aggregation in 12 healthy non-smokers, before and after 45 min supine rest in a calm environment. This simple manouver resulted in a highly significant fall in platelet aggregation (7.9-4.4 ohms, p<0.001) and in plasma epinephrine (35.6-22.5 ng/ml, p = 0.037), norepinephrine (392.8-202.7 ng/ml, p<0.001) and soluble P-selectin (51.9-44.7 ng/ml, p<0.001). Von Willebrand factor (86.2-80.9 IU/ml) and beta-thromboglobulin (279.1-262.4 IU/ml) did not change significantly. Our findings show that a person's ordinary daily routine contributes to platelet activation and aggregation, and that these can be reduced by supine rest. This has methodological implications for studies involving measures of platelet activation and aggregation, and also suggests a mechanism by which bed rest in a calm environment may contribute, however slightly, to the management of acute coronary syndromes.
authors.affiliation: Wales Heart Research Institute, University of Wales College of Medicine, Heath Park, Cardiff CF14 4XN, Wales. a.j.m.broadley@lineone.net
authors.forename: Andrew J M
authors.initials: AJ
authors.lastname: Broadley
authors.forename: Peter
authors.initials: P
authors.lastname: Gapper
authors.forename: Matthias
authors.initials: M
authors.lastname: Schmitt
authors.forename: Michael P
authors.initials: MP
authors.lastname: Frenneaux
mesh_terms: D015415:Biomarkers / Q000097:blood; D002395:Catecholamines / Q000097:blood; D006801:Humans; D019007:P-Selectin / Q000097:blood; D015539:Platelet Activation; D010974:Platelet Aggregation; D012146:Rest / Q000502:physiology*; D016683:Supine Position / Q000502:physiology*; D001620:beta-Thromboglobulin / Q000032:analysis; D014841:von Willebrand Factor / Q000032:analysis
chemical_list: D015415:Biomarkers; D002395:Catecholamines; D019007:P-Selectin; D001620:beta-Thromboglobulin; D014841:von Willebrand Factor