Germinated Buckwheat extract decreases blood pressure and nitrotyrosine immunoreactivity in aortic endothelial cells in spontaneously hypertensive rats.

Thee present study analysed the quantification of rutin in raw buckwheat extract (RBE) and germinated buckwheat extract (GBE) by high performance liquid chromatography (HPLC), and examined changes in body weight, systolic blood pressure (SBP) and nitrotyrosine (a marker for peroxynitrite formation) immunoreactivity in aortic endothelial cells in spontaneously hypertensive rats (SHRs) and normotensive Wistar-Kyoto (WKY) rats after treatment with RBE and GBE for 5 weeks. In the HPLC study, RBE and GBE contained a mean content of rutin of 1.52 +/- 0.21 and 2.92 +/- 0.88 mg/g, respectively. In the 600 mg/kg GBE-treated group, SBP was lower than that in the 600 mg/kg RBE-treated group. The treatment with RBE and/or GBE significantly reduced oxidative damage in aortic endothelial cells by lowering nitrotyrosine immunoreactivity. These results suggest that GBE has an antihypertensive effect and may protect arterial endothelial cells from oxidative stress. Copyright 2009 John Wiley & Sons, Ltd.