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Fig. 8. 4-AP blocks the inhibitory action of the enterin on the phasic contraction
of the anterior aorta. (A) The action of 10-6 mol l-1
ENpa on the phasic contraction in the absence (Ai) or presence (Aii) of 1 mmol
l-1 4-AP. The phasic contraction of the aorta was evoked by four
repetitive stimuli (2 V, 1 ms, 10 Hz) of the vulvar nerve. (B) The inhibition
of the nerve-evoked 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 relative amplitude of the contraction in
the presence of ENpa.