Fig. 4

Characterization of endothelium-dependent relaxation and contractile responses to acetylcholine in mesenteric artery rings with endothelium of the ZSF1 group. Arterial rings from the main mesenteric artery with endothelium were suspended in organ baths containing oxygenated Krebs buffer. Pharmacological inhibitors were added 20 min before the contraction to phenylephrine to assess the role of the NO-mediated component (N^ω-nitro-l-arginine, L-NA, 300 μM), the EDH-mediated component (UCL-1684 plus TRAM-34, UCL + Tram, 1 μM each), and the formation of vasoactive prostanoids (indomethacin, Indo, 10 μM). Rings were contracted with phenylephrine (1 μM) (a) or to about 20-30% of the maximal contraction (b) before the addition of increasing concentrations of acetylcholine. Values are shown as mean ± SEM of n = 8–10. *P < 0.05 vs control group