Vascular Reactivity Assessment in Rat Aorta and Mesentery

Aortic and small mesenteric arteries (SMA) were obtained from ZF or lean rats having or having not received Provinols, which were then cleaned from connective tissue and cut into rings of 1.5–2 mm long. Vessel rings were then mounted on a wire myograph (Danish MyoTechnology, Aarhus, Denmark) filled with physiological salt solution (PSS) as described previously [19 (link), 26 (link), 27 (link)]. The concentration-response curves were constructed by cumulative application of phenylephrine (Phe, 1 nmol/L to 10 μmol/L; Sigma-Aldrich, St. Quentin, Fallavier, France) to vessels with functional endothelium in the presence or absence of a given inhibitor: the NO synthase inhibitor N^ω-nitro-L-arginine methyl ester (L-NAME, 100 μmol/L; Sigma-Aldrich), the selective COX-2 inhibitor N-(2-cyclohexyloxy-4-nitrophenyl) methanesulfonamide (NS398, 10 μmol/L; Sigma-Aldrich), or indomethacin, the nonselective COX inhibitor (INDO, 100 μmol/L). All inhibitors were used at their maximal active concentrations at which they inhibit the release of either NO from all isoforms of NO synthases (L-NAME), metabolites from COX-2 isoforms (NS398), or metabolites from COX (INDO) in blood vessels, as reported in our previous studies [26 (link)].