Oxidative Stress in Hypertensive Patients Induces an Increased Contractility in Vein Grafts Independent of Endothelial Function

CLAUDIO JOO TURONI; RODRIGO MARAÑÓN; MARIA KARBINER; JUAN MUNTANER; VÍCTOR PROTO; MARÍA PERAL DE BRUNO

International Journal of Hypertension

Hindawi Publishing Corporation

Lugar: NY; Año: 2011 vol. 2011 p. 1 - 8

2090-0392

Objective. To evaluate the impact of oxidative stress on vascular reactivity to vasoconstrictors and on nitric oxide (NO) bioavailability in saphenous vein (SV) graft with endothelial dysfunction from hypertensive patients (HT). Methods. Endothelial function, vascular reactivity, oxidative state, nitrites and NO release were studied in isolated SV rings from HT and normotensive patients (NT). Only rings with endothelial dysfunction were used. Results. HT rings presented a hyperreactivity to vasoconstrictors that was reverted by diphenylene iodonium (DPI). In NT, no effect of DPI was obtained, but Nù-nitro-L-arginine methyl ester (L-NAME) increased the contractile response. NO was present in SV rings without endothelial function. Nitrites were higher in NT than in HT (1066.1 ± 86.3 pmol/mg; n=11 versus 487.8 ± 51.6; n=23; P