Tipparat ParakawKran SuknunthaPornpun VivithanapornAxel SchlagenhaufSupachai TopanurakSuthat FucharoenKovit PattanapanyasatAlan SchechterNathawut SibmoohSirada SrihirunMahidol UniversityMedizinische Universität GrazNational Institute of Diabetes and Digestive and Kidney Diseases2018-12-212019-03-142018-12-212019-03-142017-06-01Nitric Oxide - Biology and Chemistry. Vol.66, (2017), 10-1610898611108986032-s2.0-85014742723https://repository.li.mahidol.ac.th/handle/20.500.14594/41863© 2017 Elsevier Inc. In the presence of red blood cells (RBCs), nitrite inhibits platelets through its conversion to nitric oxide (NO) by the reductase activity of partially deoxygenated hemoglobin. Inhaled sodium nitrite is being investigated as a therapy for pulmonary hypertension. Here, we measured platelet aggregation, P-selectin expression, platelet-leukocyte aggregates and phosphorylated vasodilator-stimulated phosphoprotein (P-VASPSer239) following sodium nitrite inhalation in healthy subjects. In vitro incubation of nitrite with deoxygenated whole blood showed an increase in P-VASPSer239, which was inhibited by ODQ, a soluble guanylyl cyclase (sGC) inhibitor. Immediately and 60 min after nitrite inhalation, P-VASPSer239 increased in platelets. Platelet aggregation, P-selectin expression, platelet-monocyte and platelet-lymphocyte aggregates decreased after inhalation. In conclusion, sodium nitrite administered to healthy subjects by inhalation can inhibit platelet activation and increase P-VASPSer239 in platelets. Platelet inhibition by nitrite administration may be useful in disorders associated with platelet hyperactivity.Mahidol UniversityBiochemistry, Genetics and Molecular BiologyArticleSCOPUS10.1016/j.niox.2017.02.008