Estrogenized rats

P17. Prins, G. S., Marmer, M., Woodham, C., Chang, W., Kuiper, G., et al Estrogen receptor-(J messenger ribonucleic acid ontogeny in the prostate of normal and neonatally estrogenized rats. Endocrinology 139, 874-883 (1998). 

Figure 2. Scheme for isolation of purified plasma membrane fractions from longitudinal muscle of myometrium from estrogenized rats. Variations of the basic approach are used in various smooth muscles. 

The pr-MDI and bu-MDI (5x10 - - 10 M) blocked the spasmogenic action on the estrogenized rat uterus of PGF2a> PGE2, oxytocin, barium, acetylcholine, and ergonovine in a concentration-... 

RNA extracted from organ of estrogenized rats in each case. 

Post-coital activity in the rat was on the same order as estrogenic potency, with the order being CDB-1357 (ED jqo = (3 //g/kg)/d for each of5days) >... 

WS-7528 [132147-69-4][VI] a nonsteroidal estrogen, is an isoflavone which has been isolated from Streptomjces sp. No. 7528 and is an estrogen agonist. It inhibits [3ff]-estradiol binding to its receptor in rat uterine cytosol at an inhibitor for 50% of the rats tested (IC q) concentration of 5.7 nM. It also induces the growth of estrogen-dependent human breast cancer cell line MCE-7 (7). 

Steroid Hormones and Neurosteroids. Steroids (qv) can affect neuroendocrine function, stress responses, and behavioral sexual dimorphism (78,79) (see Steroids). Mineralocorticoid, glucocorticoid, androgen, estrogen, and progesterone receptors are localized in the brain and spinal cord. In addition to genomic actions, the neurosteroid can act more acutely to modulate the actions of other receptors or ion channels (80). Pregnenolone [145-13-17, ( ) dehydroepiandosterone [53-43-0] C H2 02 (319) are excitatory neurosteroids found in rat brain, independent of adrenal... 

Many stilbenelike thiophene compounds have been prepared for a study of estrogenic activity, especially by Buu-Hoi et al. Thiophene derivatives of nonhydroxylated stilbene types showed no significant activitywhereas weak estrogenic activity was found in 5-acetyl-, 5-propionyl-, and 5-benzoyl-2-(-stilbenyl)thiophene. 1-Bromo-l,2-diphenyl-2-(5-bromo-2-thienyl)ethylene (258) was found to inhibit body growth and to produce extensive testicular atropy in male rats. A thiophene analog of estrogenic isoflavones (259)... 

Organ weights and tissue development in rats administered both endosulfan and estradiol were not significantly different from those seen in rats that received estradiol alone. The study results indicate that endosulfan was neither estrogenic nor anti-estrogenic under the conditions of this assay. 

In vivo studies in animals suggest that endosulfan may disrupt normal reproductive hormone levels in male animals, but that it is not an endocrine disrupter in females. Persistent depressed testicular testosterone was seen in male rats after intermediate duration oral exposures to endosulfan. In ovariectomized female rats, orally administered endosulfan did not induce normal development of female reproductive tissues, and in female mice and immature female rats, acute parenteral exposure to endosulfan did not affect several endocrine-related end points. In vitro studies have evaluated endosulfan for estrogen receptor (ER) and cytosolic protein binding affinity, ER-mediated reporter gene expression, estrogenic induction of cell proliferation, and alteration of relative abundance of active estradiol metabolites. Overall, in vitro evidence in favor of endosulfan estrogenicity indicates relatively weak potency compared to 17[3-estradiol. Apparently contradictory results were reported in different... 

Raizada RB, Srivastava MK, Dikshith TSS. 1991. Lack of estrogenic effects of endosulfan An organochlorine insecticide in rat. Nat Acad Sci Lett 14(2) 103-107. 

Farabollini, R, Porrini, S., and Dessi-Fulgheri, F. (1999). Perinatal exposure to the estrogenic pollutant Bisphenol A affects behavior in male and female rats. Pharmacology, Biochemistry, and Behavior 64, 687-694. 

Majdic, G., Sharpe, R.M., and Oshaughnessy, PJ. et al. (1996). Expression of cytochrome P450 17 alpha-hydroxylase/C 17-20 lyase in the fetal rat testis is reduced by maternal exposure to exogenous estrogens. Endocrinology 137, 1063-1070. 

ATANASSOVA N, MCKINNELL C, TURNER K J, WALKER M, FISHER J S, MORLEY M, MILLAR M R, GROOME N p, SHARPE R M (2000) Comparative effects of neonatal exposure of male rats to potent and weak (environmental) estrogens on spermatogenesis at puberty and the relationship to adult testis size and fertility evidence for stimulatory effects of low estrogen lew eh,. Endocrinology. 141 3898-907. 

Yamaguchi and Gao, 1998 Rat femoral-metaphyseal tissues cultured for 48 h with bone resorbing factors PTH, PGE2 or EPS) +/- genistein measured bone calcium content, acid and alkaline phosphatases Genistein (10 Yi O M) inhibited bone resorption. Effect reversed by anti-estrogen, tamoxifen. 

DRAPER c R, DICK I M and PRINCE R L (1999) The effect of estrogen deficiency on calcium balance in mature rats. Calcif Tissue Int 64, 325-8. 

LiEL Y, SHANY s, SMIRNOFF p and SCHWARTZ B (1999) Estrogen increases 1,25-dihydroxyvitamin D receptors expression and bioresponse in the rat duodenal mucosa. Endocrinol 140, 280-85. 

TEN BOLSCHER M, NETELENBOS J C, BARTO R, VAN BUUREN L M, VAN DER VIJGH W J (1999) Estrogen regulation of intestinal calcimn absorption in the intact and ovariectomized aiult rat. J Bone Miner Res. 14 1197-202. 

SANTELL R c, CHANG Y c, NAIR M G and HELFERICH w G (1997) Dietary genistein exerts estrogenic effects upon the uterus, mammary gland and the hypothalamic/pituitary axis in rats. . 1 Nutr. 127 (2) 263-9. 

F3. Feldman, D., Mondon, C. E., Homer, J. A., and Weiser, J. N Glucocorticoid and estrogen regulation of corticosteroid-binding globulin production by rat liver. Am. J. Physiol. 237, E493-E499 (1979). 

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