Estrogen protects women from cardiovascular disease through an unknown mechanism. Two subtypes of estrogen receptors (ERalfa and beta)have been isolated and cloned. We have demonstrated abundant vascular expression of ERbeta in female rats and mice using immunocytochemistry. A majority of endothelial and vascular smooth muscle cell nuclei in various segments of the vascular tree showed immunoreactivity towards ERbeta. Activation of vascular ERbeta with the selective ERbeta agonist genistein stimulated protein synthesis measured as incorporation of 3H-leucine. However, we have not yet identified the ERbeta regulated proteins. Vascular preparations from ERbeta knock out mice had similar morphology and noradrenaline sensitivity as those obtained from wild-type mice. Also expression of vascular proteins (SDS PAGE) was similar in ERbeta knock out and wild-type mice. In conclusion, we have demonstrated functional vascular ERbeta.
Acknowledgement: I wish to thank my collaborators, especially prof. Jan-Ake Gustafsson at the Karolinska Institute, Huddinge, Sweden.
03 - 04 Dec 2001
Society for Endocrinology