Effect of L-NNA, ODQ and potassium channel blockers on ACh-induced relaxation of mesenteric arteries from normal and diabetic rats with or without 3′, 4′-dihydroxyflavonol (DiOHF, 1 mg/kg s.c. daily for 7 days) treatment in the presence of indomethacin.

A comparison of the sensitivity (pEC50) and maximum relaxation (Rmax) to ACh in the absence (control), or in the presence of TRAM-34 (1 µM)+apamin (1 µM), TRAM-34 (1 µM)+apamin (1 µM) +Ibtx (100 nM), 30 mM K+, L-NNA (100 µM)+ODQ (10 µM), L-NNA (100 µM)+ODQ (10 µM)+TRAM-34 (1 µM)+apamin (1 µM) or L-NNA (100 µM)+ODQ (1 µM)+TRAM-34 (1 µM)+apamin (1 µM)+Ibtx (100 nM) in endothelium intact mesenteric arteries. All experiments were conducted in the presence of indomethacin (10 µM). n = the number of experiments. *Significantly different to control within each group, p<0.05, Dunnet's test, †Significantly different to normal within inhibitor group, p<0.05, Bonferroni's test. ‡Significantly different to normal+DiOHF within inhibitor group, p<0.05, Bonferroni's test. §Significantly different to diabetic within inhibitor group, p<0.05, Bonferroni's test. Results are shown as mean±SEM, ND = Not determined.