title: The importance of Na+/H+ exchanger for the generation of procoagulant activity by porcine blood platelets.
abstract: This study addresses the role of the Na+/H+ exchanger (NHE) in the generation of procoagulant activity in blood platelets. It was found that monensin (simulating the action of NHE) and gramicidin (causing sodium influx without concomitant H+ efflux) produced a dose- and time-dependent increase in platelet procoagulant activity. Alkalinization of platelet cytosol by NH(4)Cl failed to evoke a procoagulant response. Collagen-induced procoagulant response was diminished in the absence of external Na+ and in the presence of EIPA (NHE inhibitor) or GF 109203X (protein kinase C inhibitor). Phorbol ester (PMA) produced a dose- and time-dependent generation of procoagulant response which was inhibited in the absence of the external Na+ and in the presence of EIPA. Platelets stimulated by collagen and PMA accumulated (22)Na+, a phenomenon inhibited in the presence of EIPA. The data indicate that development of procoagulant activity in platelets may occur as a result of Na+ influx via Na+/H+ exchanger.
authors.affiliation: Department of Physical Chemistry, Medical Academy of Bialystok, Mickiewicza 2A, 15-230 Bialystok, Poland.
authors.forename: J
authors.initials: J
authors.lastname: Samson
authors.forename: H
authors.initials: H
authors.lastname: Stelmach
authors.forename: M
authors.initials: M
authors.lastname: Tomasiak
mesh_terms: D000818:Animals; D001777:Blood Coagulation / Q000187:drug effects*; D001780:Blood Coagulation Tests; D001792:Blood Platelets / Q000737:chemistry / Q000187:drug effects / Q000502:physiology*; D002118:Calcium / Q000378:metabolism; D003094:Collagen / Q000494:pharmacology; D007476:Ionophores / Q000494:pharmacology; D008985:Monensin / Q000494:pharmacology; D012964:Sodium / Q000493:pharmacokinetics / Q000494:pharmacology; D017923:Sodium-Hydrogen Exchangers / Q000378:metabolism / Q000502:physiology*; D013552:Swine; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D007476:Ionophores; D017923:Sodium-Hydrogen Exchangers; D003094:Collagen; D008985:Monensin; D012964:Sodium; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium