The inhibition of NE (1 µM)-pre-contracted rat thoracic aorta rings with endothelium denuded (−E) and with intact endothelium (+E) in response to cumulative addition of SFI, HSI and FPI.

SFI can markedly suppress the intact endothelium ring contraction induced by NE, while had no obviously influence on the contraction of endothelium-denuded aorta rings (A); HSI also had a similar role as SFI (B); FPI also had no significant effect on NE-induced contraction of thoracic aorta ring with denuded and intact endothelium (C). *P<0.05, **P<0.01 vs Control (the control group was added an equal volume K-H solution).