Immunocytochemical demonstration of oestrogen receptor beta in blood vessels of the female rat

Abstract

The role of oestrogen receptor (ER) in vascular function remains unclear. With the use of a specific ER antibody we have now, using immunocytochemistry, visualized ER in different parts of the vascular tree. In about 70% of medial smooth muscle cells of female rat aorta, tail artery and uterine artery, nuclear immunoreactivity to ER was observed. In these vessels endothelial cells also expressed ER . Vascular expression of the ER subtype was lower than that of ER . In aorta and tail artery, no immunoreactivity towards ER was observed, while in uterine vessels occasional medial smooth muscle and endothelial cells expressed this ER subtype. ER and expression in uterine vessels was independent of the stage of the oestrous cycle, suggesting that variations in uterine blood flow occurring during the cycle are independent of ER density. The regional distribution of ER , as determined by immunocytochemistry, was supported by measurements of ER levels by enzyme immunoassay. In the uterine artery, the level of ER was several times higher (P<0·001) than that of aorta and tail artery (10·1 1·7 fmol/mg protein in the uterine artery vs 3·3 1·0 and 0·5 0·5 fmol/mg protein in aorta and tail artery respectively). Thus, a prominent nuclear expression of ER was observed in the vascular wall of several parts of the vascular tree, while ER predominantly was expressed in uterine vessels, suggesting that ER and may have different roles in vascular function.

Statin-induced apoptosis of vascular endothelial cells is blocked by dexamethasone

“…The past 5 years have seen a high degree of interest in the effect of oestrogens on the vasculature (Linder et al 1998, Makela et al 1999, Scheidegger et al 2000, Andersson et al 2001. This is now the first report to indicate that glucocorticoids are effective antiapoptotic agents for vascular endothelial cells.…”

Analysis of spatial and temporal expression patterns of bone morphogenetic protein family members in the rat uterus over the estrous cycle

“…Consequently, to understand the potential for cellular functions of the BMPs in the uterine vasculature, one must consider this spatial pattern of BMP-4 and -6 expression within the myometrial endothelial cells. In this concept, it should be pointed out that estrogen plays a major role in remodeling the vasculature of the rodent uterus (Clark et al 1977, Couse & Korach 1999, Page et al 2002, perhaps by activating ER expressed in the endothelial cells (Andersson et al 2001). The degree to which the endothelial-derived BMPs might contribute to the estrogen-dependent structural remodeling of the uterine vasculature remains to be determined.…”

“…In normal cycling rodents (Katsuda et al 1999, Pelletier et al 2000, Wang et al 2000, Andersson et al 2001, Mendoza-Rodríguez et al 2003 and humans (Mertens et al 2001, Punyadeera et al 2003, ER is the dominant subtype expressed in the uterus, being localized to the epithelium, stroma, myometrium and some blood vessels. By comparison, ER is more weakly expressed.…”

Gender and the Pathogenesis of Gastrointestinal Diseases: The Role of Steroid Sex Hormones in the Development

“…Vascularsmooth muscle and endothelial cells have been reported to express ERα and Erβ protein & mRNA [34][35][36]. Oestrogen has been proved to have anti-inflammatory effect by acting against inflammatory promoters, such as bacterial cell wall component, lipopolysaccharide (LPS) via activating ERα [37][38][39][40][41][42].…”