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Fig. 3. Tension recordings showing the effect of acetylcholine (ACh) on the dorsal
aorta with (A) or without (B) the presence of the soluble guanylyl cyclase
inhibitor oxadiazole quinoxalin-1 (ODQ). The vessels were pre-treated with ODQ
(10-5 mol l-1) for approximately 10 min before being
constricted with endothelin-1 (ET-1; 10-8 mol l-1). At
the peak of vasoconstriction, ACh (10-5 mol l-1) was
administered. ACh caused a constriction in the preparation incubated with ODQ
(A) and a vasodilation in the preparation without ODQ (B) (N=5).