title: Short-term treatment with nitrate is not sufficient to induce in vivo antithrombotic effects in rats and mice.
abstract: In humans, short-term supplementation with nitrate is hypotensive and inhibits platelet aggregation via an nitric oxide (NO)-dependent mechanism. In the present work, we analyzed whether short-term treatment with nitrate induces antithrombotic effects in rats and mice. Arterial thrombosis was evoked electrically in a rat model in which renovascular hypertension was induced by partial ligation of the left renal artery. In mice expressing green fluorescent protein, laser-induced thrombosis was analyzed intravitally by using confocal microscope. Sodium nitrate (NaNO3) or sodium nitrite (NaNO2) was administered orally at a dose of 0.17 mmol/kg, twice per day for 3 days. Short-term nitrate treatment did not modify thrombus formation in either rats or mice, while nitrite administration led to pronounced antithrombotic activity. In hypertensive rats, nitrite treatment resulted in a significant decrease in thrombus weight (0.50 ± 0.08 mg vs. VEH 0.96 ± 0.09 mg; p < 0.01). In addition, nitrite inhibited ex vivo platelet aggregation and thromboxane B2(TxB2) generation and prolonged prothrombin time. These effects were accompanied by significant increases in blood NOHb concentration and plasma nitrite concentration. In contrast, nitrate did not affect ex vivo platelet aggregation or prothrombin time and led to only slightly elevated nitrite plasma concentration. In mice, nitrate was also ineffective, while nitrite led to decreased platelet accumulation in the area of laser-induced endothelial injury. In conclusion, although nitrite induced profound NO-dependent antithrombotic effects in vivo, conversion of nitrates to nitrite in rats and mice over short-term 3-day treatment was not sufficient to elicit NO-dependent antiplatelet or antithrombotic effects.
authors.affiliation: Department of Biopharmacy, Medical University of Bialystok, Mickiewicza 2C Str, 15-222, Bialystok, Poland.
authors.forename: K
authors.initials: K
authors.lastname: Kramkowski
authors.affiliation: Department of Biopharmacy, Medical University of Bialystok, Mickiewicza 2C Str, 15-222, Bialystok, Poland.
authors.forename: A
authors.initials: A
authors.lastname: Leszczynska
authors.affiliation: Jagiellonian Centre of Experimental Therapeutics (JCET), Jagiellonian University, Bobrzynskiego 14, 30-348, Krakow, Poland.
authors.forename: K
authors.initials: K
authors.lastname: Przyborowski
authors.affiliation: Jagiellonian Centre of Experimental Therapeutics (JCET), Jagiellonian University, Bobrzynskiego 14, 30-348, Krakow, Poland.
authors.forename: B
authors.initials: B
authors.lastname: Proniewski
authors.affiliation: Department of Biopharmacy, Medical University of Bialystok, Mickiewicza 2C Str, 15-222, Bialystok, Poland.
authors.forename: N
authors.initials: N
authors.lastname: Marcinczyk
authors.affiliation: Department of Biopharmacy, Medical University of Bialystok, Mickiewicza 2C Str, 15-222, Bialystok, Poland.
authors.forename: U
authors.initials: U
authors.lastname: Rykaczewska
authors.affiliation: Department of Biopharmacy, Medical University of Bialystok, Mickiewicza 2C Str, 15-222, Bialystok, Poland.
authors.forename: D
authors.initials: D
authors.lastname: Jarmoc
authors.affiliation: Department of Biopharmacy, Medical University of Bialystok, Mickiewicza 2C Str, 15-222, Bialystok, Poland.
authors.forename: E
authors.initials: E
authors.lastname: Chabielska
authors.affiliation: Jagiellonian Centre of Experimental Therapeutics (JCET), Jagiellonian University, Bobrzynskiego 14, 30-348, Krakow, Poland. stefan.chlopicki@jcet.eu.|Chair of Pharmacology, Jagiellonian University Medical College, Grzegórzecka 16, 31-531, Krakow, Poland. stefan.chlopicki@jcet.eu.
authors.forename: S
authors.initials: S
authors.lastname: Chlopicki
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000097:blood; D001777:Blood Coagulation / Q000187:drug effects*; D004195:Disease Models, Animal; D005343:Fibrinolytic Agents / Q000494:pharmacology*; D006442:Glycated Hemoglobin / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D006978:Hypertension, Renovascular / Q000150:complications; D007834:Lasers; D008297:Male; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009566:Nitrates / Q000097:blood / Q000494:pharmacology*; D009569:Nitric Oxide / Q000378:metabolism; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D011517:Prothrombin Time; D017208:Rats, Wistar; D012977:Sodium Nitrite / Q000097:blood / Q000494:pharmacology*; D013927:Thrombosis / Q000097:blood / Q000209:etiology / Q000517:prevention & control*; D013929:Thromboxane B2 / Q000378:metabolism; D013997:Time Factors
chemical_list: D015415:Biomarkers; D005343:Fibrinolytic Agents; D006442:Glycated Hemoglobin; D049452:Green Fluorescent Proteins; D009566:Nitrates; D009569:Nitric Oxide; D010975:Platelet Aggregation Inhibitors; D012977:Sodium Nitrite; D013929:Thromboxane B2; C058377:hemoglobin A, glycosylated-nitric oxide complex; C031618:sodium nitrate
keywords: Nitrate; Nitric oxide; Nitrite; Platelet; Thrombosis