The influence of temperature on platelet hemostasis induced by various agonists

Abstract

   Platelet activation, shape change and aggregation are active processes that can be significantly dependent on the ambient temperature. However, there are conflicting data in the literature regarding the effect of temperature on platelets. In our work, we used a laser diffraction method to investigate the influence of temperature on the reaction of human platelets activated byvarious agonists: ADP, U46619 (thromboxane mimetic), and thrombin (TRAP-6), that act through G-protein coupled receptors, and collagen, that activates the immunoglobulin receptor GPVI. For agonists that activate G-protein coupled receptors, we showed that an increase in temperature causes an acceleration of the initial platelet activation (shape change) and has nosignificant effect on agonist sensitivity (EC50). At the same time, hypothermia at low doses of such agonists potentiates platelet aggregation, which differs significantly from the effect of collagen. With increasing temperature, collagen accelerates platelet aggregation over the entire range of temperatures investigated. In this paper, we showed that the effect of temperature on platelet activation processes depends on both the dose of agonists and the type of activated receptors. In our study, we included healthy volunteers after obtaining a written informed consent. Blood samples were taken in accordance with the guidelines of the I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences and the Declaration of Helsinki. Studies with human erythrocytes were approved by the Ethics Committee of the I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences (Protocol No.3–03 dated 2 March 2021 and Protocol No.1–04 dated 7 April 2022).