Fig. 9. 4-AP does not affect the inhibitory action of the enterin on the NdWFamide-evoked contraction of the anterior aorta. (A) Relaxation of the NdWFamide-induced contraction by ENpa in the absence (Ai) or presence (Aii) of 1 mmol l^-1 4-AP. The aorta was contracted by 10^-7 mol l^-1 NdWFamide, and the action of 10^-6 mol l^-1 ENpa was tested. (B) The inhibition of the NdWFamide-induced contraction by ENpa in the absence [4-AP(-)] or the presence [4-AP(+)] of 1 mmol l^-1 4-AP. Histograms show means ± S.E.M. (N=4) of the normalized NdWFamide-induced contraction in the presence of ENpa.