A Comparative Study of Estrogen Receptors α and β in the Rat Uterus1

Wang, Han-sen; Masironi, Britt; Eriksson, Håkan; Sahlin, Lena

doi:10.1095/biolreprod61.4.955

Cited by 134 publications

(113 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In mammals, two nuclear receptors mediate the actions by stimulating the binding of estrogen, the α-and β-estrogen receptors, having the predominance of α-estrogen receptors in the uterus (Klinge 2001, Nilsson et al 2001, Wang et al 1999. This also reflects in higher affinity of the metabolite α-zearalenol to bind estrogen receptors (Takemura et al 2007) and greater susceptibility of pigs to the effects of ZEA by the predominance in the production of this metabolite (Malekinejad et al 2006).…”

Section: Discussionmentioning

confidence: 99%

Effects of zearalenone in prepubertal gilts

Teixeira¹,

Montiani‐Ferreira²,

Locatelli-Dittrich³

et al. 2011

Pesq. Vet. Bras.

View full text Add to dashboard Cite

Prepubertal gilts were fed with a diet containing zearalenone (ZEA) in a concentration of 0.75 mg/kg for 21 days. The effects of this mycotoxin on morphologic aspects of the reproductive tract as well as on complete blood count (CBC), serum biochemistry analysis (SBA) and humoral immune response against sheep red blood cells (SRBC) were evaluated. There was a significant increase (P<0.05) on the reproductive tract weight, vulvar area, height of the epithelial cells of endometrial glands and uterine mucosa. These results showed the ability of this nonsteroidal mycotoxin in mimicking actions of 17β estradiol at the concentration of 0.75mg/kg. No changes in weight gain, CBC, SBA parameters and humoral response against SRBC were observed.

show abstract

Section: Discussionmentioning

confidence: 99%

Effects of zearalenone in prepubertal gilts

Teixeira¹,

Montiani‐Ferreira²,

Locatelli-Dittrich³

et al. 2011

Pesq. Vet. Bras.

View full text Add to dashboard Cite

show abstract

“…The recently discovered beta receptor (ER␤) is present at very low levels in the uterus, and it is not clear whether functional levels of ER␤ protein are present (43)(44)(45). Zhong and coworkers (41) also have demonstrated that nongenomic effects of E2 occur through ER␣ stimulation.…”

Section: Discussionmentioning

confidence: 99%

Estradiol rapidly inhibits soluble guanylyl cyclase expression in rat uterus

Krumenacker¹,

Hyder²,

Murad³

2001

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Previous reports that investigated the regulation of the NO͞ soluble guanylyl cyclase (sGC)͞cGMP pathway by estrogenic compounds have focused primarily on the levels of NO, NO-producing enzymes, and cGMP in various tissues. In this study, we demonstrate that 17␤-estradiol (E2) regulates the ␣1 and ␤1 subunits of the NO receptor, sGC, at the mRNA and protein levels in rat uterus. Using real-time quantitative PCR, we found that within 1 h of in vivo E2 administration to rats, sGC mRNA levels begin to diminish. After 3 h, there is a maximal diminution of sGC mRNA expression (sGC ␣1 10% and sGC ␤1 33% of untreated). This effect was blocked by the estrogen receptor antagonist, ICI 182,780, indicating that estrogen receptor is required. The effect of E2 also was observed in vitro with incubations of uterine tissue, indicating that the response does not depend on the secondary release of other hormones or factors from other tissues. Puromycin did not block the effect, suggesting the effects occur because of preexisting factors in uterine tissues and do not require new protein synthesis. Using immunoblot analysis, we found that sGC protein levels also were reduced by E2 over a similar time course as the sGC mRNA. We conclude that sGC plays a vital role in the NO͞sGC͞cGMP regulatory pathway during conditions of elevated estrogen levels in the rat uterus as a result of the reduction of sGC expression.nitric oxide ͉ gene regulation ͉ steroid hormone T he steroid hormone 17␤-estradiol (E2) exhibits dramatic effects in the uterus with respect to hyperemia, gene expression, and proliferation of the endometrium. It is clear that there is a wide array of changes in the expression of multiple genes and biochemical processes within the uterus after E2 exposure. However, as a whole, it is unclear how these responses mediate the hyperemic and subsequent proliferative response of the uterine tissue.To understand how these processes are regulated is essential, because normal physiological, pathological, and pharmacological estrogenic responses are common. For instance, the levels of estrogen are tightly regulated and mediate uterine quiescence and initiation of labor during pregnancy (1). In addition, estrogen levels fluctuate during the estrous cycle of mammals and the menstrual cycle of primates, which mediate the endometrial growth cycle (2). Postmenopausal women frequently are administered estrogen supplements in hormone replacement therapy regimens to reduce the loss of bone mass associated with menopause. Furthermore, use of the anti-estrogen, tamoxifen, for treating breast cancer results in paradoxical estrogenic effects in the uterus (3). Finally, both men and women are exposed to low levels of phyto-estrogens on a daily basis, dependent on dietary and environmental intake (4).Reports indicate that estrogens regulate the NO͞soluble guanylyl cyclase (sGC)͞cGMP cell signaling pathway and the levels of NO and the second messenger, cGMP, in many tissues, including the uterus. Recent and past studies have investigated the levels o...

show abstract

“…Recent studies (Hiroi et al, 1999;Wang et al, 1999;Nephew et al, 2000) indicate that the dominant receptor subtype in the rat endometrium is ERα, which is localized in nuclei of the luminal and glandular epithelium and in the stroma. The effect of E 2 on uterine ER in OVX rats is apparently biphasic.…”

Section: Discussionmentioning

confidence: 99%

Estrogenic effects of silymarin in ovariectomized rats

Kummer¹,

Mašková²,

Čanderle³

et al. 2001

Vet. Med. - Czech

View full text Add to dashboard Cite

The objective of this study was to test whether silymarin induces changes indicative of estrogenic effects in gonadal organs of ovariectomized (OVX) rats. Silymarin was administered in two experimental groups of OVX rats (n = 7 + 7) for 30 days at the doses of 25 or 50 mg per animal per day. OVX rats (n = 7) receiving 5 µg of 17b-estradiol (E2) for the last three days before killing and untreated OVX rats (n = 7) were used as the positive and the negative controls, respectively. Uterine and blood samples were collected immediately after killing. Compared with the negative controls, total and normalized uterine weights were significantly higher in the two experimental groups (P < 0.01 and P < 0.05, respectively). Uterotrophic effects of silymarin were also evident from increased heights of the luminal epithelium (P < 0.01) and the endometrium (P < 0.05). The response was dose-independent within the tested range. The strongest uterine response was observed in the OVX rats treated with E2. A highly significant decrease in mean density of estrogen receptor (ERa) immunostaining in the luminal and the glandular endometrial epithelia (P < 0.01) and a stronger ERa immunostaining in stromal cells were observed in the two experimental and the positive control groups. The activities of alkaline and acid phosphatases were significantly increased in the luminal (P < 0.05) and the glandular (P < 0.01) epithelia only in the rats treated with E2. Both silymarin and E2 induced an increase in thyroid hormone concentrations in blood serum. The rises of free T3 and T4 were significant (P < 0.05) in the group receiving 50 mg of silymarin per day. Hepatic oxidative metabolism of steroids was assumed to be another target of the action of silymarin. The mitochondrial cytochrome P450-dependent testosterone hydroxylase activity and the cytochrome P4501A-dependent 7-ethoxyresorufin O-deethylase activity were significantly increased (P < 0.05) in the group receiving 50 mg of silymarin per day and in the E2-treated control group, respectively. However, the modulations of the CYP enzymes played only a minor role in the overall estrogenic effect of silymarin. Histological and functional alterations in the OVX rats treated orally with silymarin for 30 days were consistent with those seen in E2-treated rats and were indicative of estrogenic effects of silymarin.

show abstract

A Comparative Study of Estrogen Receptors α and β in the Rat Uterus1

Cited by 134 publications

References 48 publications

Effects of zearalenone in prepubertal gilts

Effects of zearalenone in prepubertal gilts

Estradiol rapidly inhibits soluble guanylyl cyclase expression in rat uterus

Estrogenic effects of silymarin in ovariectomized rats

Contact Info

Product

Resources

About