Figure 5.

Concentration-response curves for peak amplitude of responses to bolus injections (10 μl) of N-substituted S-nitrosothiols into the perfusate of (a) endothelium-intact vessels, (b) endothelium-denuded vessels and (c) endothelium-denuded vessels perfused with 10 μM Hb (n=8 for all compounds under each condition). There was no statistical significant difference between responses to any of the SNAP analogues in either (a) or (b) (P>0.05; repeated dose, 2 factor ANOVAs). Responses to SNVP and SNHP, but not the other analogues, were significantly enhanced in (b) compared to (a) and responses to all four analogues were significantly inhibited by Hb (c; P<0.05).