Abstract
Apple (Malus pumila) procyanidins led to a potent vasorelaxation effect μMin 1.0 μM phenylephrine-contractive rat thoracic aorta. Relaxation was greatly reduced by 70 mm KCl as well as by removal of the endothelium, suggesting that it was associated with endothelium- dependent hyperpolarization. Neither cAMP synthesis inhibition nor NAD(P)H oxidase inhibition abolished the effect. In contrast, complete abolition by a soluble guanylyl cyclase inhibitor revealed that apple procya- nidins were mainly involved in the cGMP production pathways. In the presence of NG-monoethyl-l-arginine or tetraethylammonium chloride, the effect was still observed at higher concentrations (>25 μ, g/ml), while their combination completely diminished the effect. Vasorelaxation was to some extent affected by paxillin, apamin and glybenclamide, and was greatly affected by 4-aminopyridine and by BaCl2. These results indicate that procyanidin-induced vasorelaxation is associated with NO-cGMP pathway in combination with hyper- polarization due to multiple activation of Ca2+-dependent and -independent K + channels.
Original language | English |
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Pages (from-to) | 2246-2251 |
Number of pages | 6 |
Journal | Bioscience, Biotechnology and Biochemistry |
Volume | 73 |
Issue number | 10 |
DOIs | |
Publication status | Published - 2009 |
All Science Journal Classification (ASJC) codes
- Biotechnology
- Analytical Chemistry
- Biochemistry
- Applied Microbiology and Biotechnology
- Molecular Biology
- Organic Chemistry