Abstract
The effects of estrogen on arterial function are heterogeneous with respect to vessel and/or species. We have investigated 17β-estradiol-induced relaxation in isolated rat aorta with regard to the role of the vascular endothelium and ionic mechanisms. Estrogen induced a concentration-dependent relaxation of 46.5 ± 7.9% and 70.1 ± 12.2% (10-8 and 10-7 M), which was reduced by endothelial denudation. Furthermore, L-nitroarginine methyl ester completely abrogated this effect; however, estradiol did not relax KCl-contracted rings. Tetraethyl ammonium (1 mmol/l) completely blocked estradiol-induced relaxation. Estradiol increased [cGMP] in isolated aortic rings via NO, but did not significantly affect NOS activity in endothelial cells. Thus, estrogen can relax rat aorta in vitro via both endothelium-dependent and -independent mechanisms involving the NO/cGMP and potassium channel signaling system.
Original language | English (US) |
---|---|
Pages (from-to) | 20-26 |
Number of pages | 7 |
Journal | Pharmacology |
Volume | 69 |
Issue number | 1 |
DOIs | |
State | Published - 2003 |
Keywords
- Aorta
- Estrogen
- Nitric oxide
- Potassium channel
ASJC Scopus subject areas
- Pharmacology