189 Differential Effects of Resveratol on Acetylcholine-Induced and Flow-Mediated Dilation of the Mouse Femoral Artery

Despite the widespread use of nutritional supplements, insight into their potential beneficial or harmful biological effects is frequently lacking. Resveratrol (RV) is a polyphenol found in berries and grape skin and is often marketed as beneficial for vascular health. Here, we tested this assumption and hypothesised that RV enhances endothelial function and flow-mediated dilation (FMD) in mouse femoral arteries.C57BL/6 male mice (12 weeks of age) were humanely euthanised in accordance with the ‘Animals (Scientific Procedures) Act 1986’ and Institutional guidelines. Sections of the femoral artery were dissected and mounted between two glass cannulae on a modified pressure myograph chamber. Arteries were pressurised to an intravascular pressure of 60 mmHg. Endothelial-dependent dilator responses to acetylcholine (ACh) and intraluminal flow in pre-constricted vessels (Phe 10–5 M) were assessed in femoral arteries incubated for 1 h in either 30 µM RV or physiological saline solution (PSS). The contribution of different vasodilator pathways was investigated by treating sections of the femoral artery with L-NG-nitro-L-arginine (L-NNA; 100uM) or indomethacin (10 µM). The drugs were applied intraluminally for 30 min using a 1-mL syringe inserted into one end of a 3‐way luer connexion on the side of the pressure myograph chamber while incubated in PSS or RV. After 30 min incubation, dilator responses to ACh (10–9–10–3 M) and intraluminal flow (5–10 µL·min-1) in the presence or absence of these drugs were determined.Maximal degrees of dilation were reached upon perfusing the arteries with of 10–5 to 10–3 M ACh. RV treatment significantly enhanced dilation in response to ACh (p < 0.05). Whereas dilation of the arteries in response to ACh was (mean ± SEM) 68.1 ± 13.7% (n = 9) of the passive diameter when incubated with PSS, treatment with RV resulted in dilation of 92.2 ± 13.4% (n = 6). However, RV significantly reduced FMD (p < 0.05); dilation in response to intraluminal flow of 8 µL·min-1 was 22.5 ± 7.1% (n = 9) and 0.67 ± 1.06% (n = 6) of the passive when the sections were incubated with PSS and RV, respectively. Incubation with L-NNA reduced dilation to ACh in the presence of RV. However, the effects of RV on ACh dilation were maintained in the presence of indomethacin. The effects of RV on FMD were not significantly modulated by L-NNA or indomethacin. The responses to intraluminal flow were still compromised and no significant dilation was present. O