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Fig. 5. Tension recordings showing the vasodilatory effect of acetylcholine (ACh)
on the lateral aorta with the endothelium removed (A) and with the endothelium
intact (A). The preparations were exposed to endothelin-1 (ET-1;
10-8 mol l-1) until a maximum constriction was achieved
and then ACh (10-5 mol l-1) was added. (C) Mean response
(% vasodilation) of ACh on pre-constricted lateral and dorsal aortae with the
endothelium removed (filled bars) or the endothelium intact (open bars). Note
that there is no significant difference in the ACh-mediated dilation (lateral
aortae, P=0.26; dorsal aorta, P=0.35; N=5).