Effect on Vascular Endothelium-Independent Relaxation.
Treatment of OVX rats with 17β-estradiol, C. comosa
powder, compound D3, and C. comosa hexane extract for 12
weeks did not significantly alter the relaxation of aortic ring
without endothelium (denuded) in response to SNP (Figure
3). EC50 values of the SNP-induced vascular relaxation in all
experimental groups were comparable, suggesting that both the
maximum relaxation and the sensitivity of the relaxation
response to SNP in denuded vascular were not affected.
These findings indicate that the site of action of estrogen, as
well as C. comosa, in preventing impairment of vascular
relaxation is at the endothelial lining cells and not smooth
muscle cells.