Estrogen receptor beta dominates in baboon carotid after endothelial denudation injury

Increasing evidence, mainly from rodents, suggests that the predominant est rogen receptor (ER) in arteries is the newly-described ERbeta. We have inve stigated the expression of the two ERs in baboon carotid artery before and after denudation injury. Prior to denudation, both Cull length receptors we re detected in semiquantitative RT-PCR; in addition two ERalpha but no ERbe ta splicing variants were found. After denudation, ERbeta mRNA increased fi ve-fold and declined, whereas ERalpha mRNA expression remained low. Prior t o and after denudation, two ERalpha-specific antibodies showed no reaction with the vessel wall. Instead, two affinity purified antisera to ERbeta dem onstrated a weak but distinct reaction over vascular smooth muscle cells wi th predenudation specimen, escalating post-denudation and declining thereaf ter. The results suggest that selective targeting to ERbeta should be attem pted when designing estrogen-based vasculoprotective drug therapies devoid of uterotrophic side effects. (C) 2001 Elsevier Science Ireland Ltd. All ri ghts reserved.