207 The Vascular Effects of Resveratrol on Aged Mouse Femoral Arteries

Background In addition to its antioxidant properties, resveratrol (RV) is also known for its vasodilating effects. Although some of the vasodilating mechanisms of RV have been attributed to increases in NO, it has been previously demonstrated that in dietary-obese rats, in which endothelial function is impaired, RV is able to promote >95% dilation. Given the above observations, we hypothesised that RV treatment restores endothelial function and flow mediated dilation of femoral arteries in old mice. Methods To establish vasodilator responses, C57BL/6 male mice (105 weeks of age) were humanely euthanised in accordance with the ‘Animals (Scientific Procedures) Act 1986’ and Institutional guidelines. Sections of the femoral artery were carefully dissected and mounted between two glass cannulae and fixed in place on a modified pressure myograph chamber. Arteries were initially pressurised to an intravascular (lumenal) pressure of 60 mmHg and maintained at that pressure using a pressure servo-control unit. Lumen and internal diameters of the vessel were constantly measured using a video dimension analyser. Constrictor responses (Phenylephrine (Phe) 10 –9 –10 –3 M) and endothelial-dependent dilator responses to acetylcholine (Ach; 10 –9 –10 –3 M) and flow (5–10 µL·min –1 ) in pre-constricted vessels (Phe 10 –5 M) were assessed in femoral arteries incubated for 1 hr in either RV (30 µM) or physiological saline solution (PSS). The dilator responses were calculated as percentage of the pre-constrictor diameter, Results and conclusion RV treatment had no significant effect on Ach-dependent dilator responses. Whereas intraluminal flow of 8µL·min –1 increased the diameter of the femoral arteries by up to 80% of the original diameter when arteries were pre-constricted and incubated in PSS, we observed no dilation after treatment with RV. Our data suggest that RV may have differential effects on Ach-dependent and flow mediated dilator responses in femoral arteries from aged mice.