TY - JOUR
T1 - Rapid activation of endothelial nitric oxide synthase by estrogen
AU - Shaul, Philip W.
N1 - Funding Information:
We are indebted to Marilyn Dixon for preparing this manuscript. This work was supported by National Institutes of Health grants HL58888, HL53546 and HD30276, and an Established Investigatorship of the American Heart Association.
PY - 1999/1
Y1 - 1999/1
N2 - Estrogen is an important atheroprotective molecule that causes the rapid dilation of blood vessels by stimulating endothelial nitric oxide synthase (eNOS). There is also evidence that estrogen modulates airway epithelial NO production, thereby potentially affecting bronchial hyperresponsiveness. Studies in cultured endothelial and airway epithelial cells indicate that physiologic concentrations of estrogen cause rapid direct activation of eNOS that is unaffected by actinomycin D, but fully inhibited by estrogen receptor (ER) antagonism. Overexpression of ERα leads to marked enhancement of the acute response to estrogen, and this process is blocked by ER antagonism, it is specific to estrogen, and it requires the ERα hormone binding domain. In addition, the acute response of eNOS to estrogen can be reconstituted in COS- 7 cells cotransfected with wild-type ERα and eNOS, but not by transfection with eNOS alone. Furthermore, the inhibition of calcium influx, or tyrosine kinases or MAP kinase prevents the stimulation of eNOS by estrogen, and estrogen causes rapid ER-dependent activation of MAP kinase. These findings indicate that the acute effects of estrogen on both endothelial and airway epithelial eNOS are mediated by ERα functioning in a novel, nongenomic manner to activate the enzyme via calcium-dependent, MAP kinase-dependent mechanisms.
AB - Estrogen is an important atheroprotective molecule that causes the rapid dilation of blood vessels by stimulating endothelial nitric oxide synthase (eNOS). There is also evidence that estrogen modulates airway epithelial NO production, thereby potentially affecting bronchial hyperresponsiveness. Studies in cultured endothelial and airway epithelial cells indicate that physiologic concentrations of estrogen cause rapid direct activation of eNOS that is unaffected by actinomycin D, but fully inhibited by estrogen receptor (ER) antagonism. Overexpression of ERα leads to marked enhancement of the acute response to estrogen, and this process is blocked by ER antagonism, it is specific to estrogen, and it requires the ERα hormone binding domain. In addition, the acute response of eNOS to estrogen can be reconstituted in COS- 7 cells cotransfected with wild-type ERα and eNOS, but not by transfection with eNOS alone. Furthermore, the inhibition of calcium influx, or tyrosine kinases or MAP kinase prevents the stimulation of eNOS by estrogen, and estrogen causes rapid ER-dependent activation of MAP kinase. These findings indicate that the acute effects of estrogen on both endothelial and airway epithelial eNOS are mediated by ERα functioning in a novel, nongenomic manner to activate the enzyme via calcium-dependent, MAP kinase-dependent mechanisms.
KW - Estrogen
KW - Estrogen receptor
KW - Nitric oxide synthase
KW - Steroid
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U2 - 10.1016/S0039-128X(98)00105-6
DO - 10.1016/S0039-128X(98)00105-6
M3 - Article
C2 - 10323670
AN - SCOPUS:0032898708
SN - 0039-128X
VL - 64
SP - 28
EP - 34
JO - Steroids
JF - Steroids
IS - 1-2
ER -