scholarly journals Modification of Gene Expression of Connexins in the Rat Corpus Epididymis by Estradiol Benzoate or Flutamide Exposure at the Early Neonatal Age

2015 ◽  
Vol 19 (2) ◽  
pp. 69-77 ◽  
Author(s):  
Ki-Ho Lee
Keyword(s):  
Gene Expression ◽  
Estradiol Benzoate

scholarly journals Modulation of responses to stress by estradiol benzoate and selective estrogen receptor agonists

2010 ◽  
Vol 205 (3) ◽  
pp. 253-262 ◽  
Author(s):  
Lidia I Serova ◽  
Heather A Harris ◽  
Shreekrishna Maharjan ◽  
Esther L Sabban
Keyword(s):  
Gene Expression ◽  
Estrogen Receptor ◽  
Hpa Axis ◽  
Immobilization Stress ◽  
Estradiol Benzoate ◽  
Female Rats ◽  
Reduced Body ◽  
Ovx Rats ◽  
Selective Agonists

Previously, pretreatment with estradiol benzoate (EB) was found to modulate the response of hypothalamic–pituitary–adrenal (HPA) axis and gene expression in several catecholaminergic neuronal locations in ovariectomized (OVX) rats exposed to single immobilization stress (IMO). Here, we investigated the role of estrogen receptor (ER) subtypes, using selective agonists for ERα (propyl pyrazole triol, PPT) or ERβ (WAY-200070) in two major central noradrenergic systems and the HPA axis after exposure to single and repeated IMO. OVX female rats received 21 daily injections of either EB (25 μg/kg), PPT (10 mg/kg), WAY-200070 (10 mg/kg), or vehicle. Injections of EB and PPT, but not WAY-200070, elicited reduced body weight and increased uterine weight, showing their selectivity. Both EB and PPT increased corticosterone levels about two- to threefold, but prevented any further rise with either single or repeated IMO, indicating an ERα (ESR1)-, but not ERβ (ESR2)-, mediated mechanism. In the locus coeruleus (LC), the rise in dopamine-β-hydroxylase (Dbh) mRNA with both stress paradigms was abrogated in EB- or PPT-injected animals. However, WAY-200070 blocked the response of DBH mRNA to single IMO but not to repeated IMO. In the nucleus of the solitary tract (NTS), the rise in tyrosine hydroxylase and DBH mRNAs with both IMOs was absent, or greatly attenuated, in EB- or PPT-treated rats. In most cases, WAY-200070 inhibited the response to single IMO but not to repeated IMO. The results demonstrate that pretreatment with estradiol, or ER-selective agonists, modulates the stress-triggered induction of gene expression of norepinephrine biosynthetic enzymes in LC and NTS, with ER selectivity depending on duration of the stress.

scholarly journals Disruption of Reproductive Aging in Female and Male Rats by Gestational Exposure to Estrogenic Endocrine Disruptors

Endocrinology ◽  
2013 ◽  
Vol 154 (6) ◽  
pp. 2129-2143 ◽  
Author(s):  
Deena M. Walker ◽  
Bailey A. Kermath ◽  
Michael J. Woller ◽  
Andrea C. Gore
Keyword(s):  
Gene Expression ◽  
Median Eminence ◽  
Endocrine Disrupting Chemicals ◽  
Estradiol Benzoate ◽  
Sexually Dimorphic ◽  
Reproductive Aging ◽  
Gestational Exposure ◽  
Hypothalamic Nuclei ◽  
Endocrine Disrupting ◽  
Aroclor 1221

Abstract Polychlorinated biphenyls (PCBs) are industrial contaminants and known endocrine-disrupting chemicals. Previous work has shown that gestational exposure to PCBs cause changes in reproductive neuroendocrine processes. Here we extended work farther down the life spectrum and tested the hypothesis that early life exposure to Aroclor 1221 (A1221), a mixture of primarily estrogenic PCBs, results in sexually dimorphic aging-associated alterations to reproductive parameters in rats, and gene expression changes in hypothalamic nuclei that regulate reproductive function. Pregnant Sprague Dawley rats were injected on gestational days 16 and 18 with vehicle (dimethylsulfoxide), A1221 (1 mg/kg), or estradiol benzoate (50 μg/kg). Developmental parameters, estrous cyclicity (females), and timing of reproductive senescence were monitored in the offspring through 9 months of age. Expression of 48 genes was measured in 3 hypothalamic nuclei: the anteroventral periventricular nucleus (AVPV), arcuate nucleus (ARC), and median eminence (females only) by real-time RT-PCR. Serum LH, testosterone, and estradiol were assayed in the same animals. In males, A1221 had no effects; however, prenatal estradiol benzoate increased serum estradiol, gene expression in the AVPV (1 gene), and ARC (2 genes) compared with controls. In females, estrous cycles were longer in the A1221-exposed females throughout the life cycle. Gene expression was not affected in the AVPV, but significant changes were caused by A1221 in the ARC and median eminence as a function of cycling status. Bionetwork analysis demonstrated fundamental differences in physiology and gene expression between cycling and acyclic females independent of treatment. Thus, gestational exposure to biologically relevant levels of estrogenic endocrine-disrupting chemicals has sexually dimorphic effects, with an altered transition to reproductive aging in female rats but relatively little effect in males.

Transgenerational effects of polychlorinated biphenyls: 2. Hypothalamic gene expression in rats

2021 ◽  
Author(s):  
Andrea C Gore ◽  
Lindsay M Thompson ◽  
Mandee Bell ◽  
Jan A Mennigen
Keyword(s):  
Gene Expression ◽  
Polychlorinated Biphenyls ◽  
Expression Profiles ◽  
Endocrine Disrupting Chemicals ◽  
Gene Expression Profiles ◽  
Estradiol Benzoate ◽  
Dependent Manner ◽  
Sprague Dawley ◽  
Transgenerational Effects ◽  
Aroclor 1221

Abstract Polychlorinated biphenyls (PCBs) are endocrine-disrupting chemicals (EDCs) with well-established effects on reproduction and behavior in developmentally-exposed (F1) individuals. Because of evidence for transgenerational effects of EDCs on the neuroendocrine control of reproductive physiology, we tested the hypothesis that prenatal PCB exposure leads to unique hypothalamic gene expression profiles in three generations. Pregnant Sprague–Dawley rats were treated on gestational days 16 and 18 with the PCB mixture Aroclor 1221 (A1221), vehicle (3% DMSO in sesame oil), or estradiol benzoate (EB, 50 μg/kg), the latter a positive control for estrogenic effects of A1221. Maternal- and paternal-lineage F2 and F3 generations were bred using untreated partners. The anteroventral periventricular nucleus (AVPV) and arcuate nucleus (ARC), involved in the hypothalamic control of reproduction, were dissected from F1-F3 females and males, RNA extracted, and gene expression measured in a qPCR array. We detected unique gene expression profiles in each generation, that were sex- and lineage-specific. In the AVPV, treatment significantly changed 10, 25, and 11 transcripts in F1, F2, and F3 generations, whereas 10, 1, and 12 transcripts were changed in these generations in the ARC. In the F1 AVPV and ARC, most affected transcripts were decreased by A1221. In the F2 AVPV, most effects of A1221 were observed in females of the maternal lineage, whereas only Pomc expression changed in the F2 ARC (by EB). The F3 AVPV and ARC were mainly affected by EB. It is notable that results in one generation do not predict results in another, and that lineage was a major determinant in results. Thus, transient prenatal exposure of F1 rats to A1221 or EB can alter hypothalamic gene expression across 3 generations in a sex- and lineage-dependent manner, leading to the conclusion that the legacy of PCBs continues for generations.

scholarly journals Effect of medroxy-progesterone acetate on follicular growth and endometrial cycloxygenase-2 (COX-2) expression during the bovine estrous cycle

2010 ◽  
Vol 30 (7) ◽  
pp. 581-585 ◽  
Author(s):  
Valério M. Portela ◽  
Alexandre M. Farias ◽  
José C. Ferrugem Moraes ◽  
Paulo Bayard D. Gonçalves ◽  
Angela P. Medeiros Veiga ◽  
...  
Keyword(s):  
Gene Expression ◽  
Estrous Cycle ◽  
Estradiol Benzoate ◽  
Synthetic Analogue ◽  
Mrna Levels ◽  
Follicular Growth ◽  
Cox 2 ◽  
Different Doses

The objective of this study was to evaluate the effect of medroxy-progesterone acetate (MAP) with or without estradiol benzoate (EB) on follicular growth during the estrous cycle in cattle. In the first experiment, Hereford cows were synchronized with a synthetic analogue of PGF2 alpha and were treated with two different doses of MAP (250 or 500 mg) with or without EB for 7 days starting on day 8 of the estrous cycle. Follicular growth was inhibited (P<0.05) in all cows except controls and those receiving 250mg MAP without EB. Seventy-five percent of the animals (15/20) showed estrus on days 21 and 22 of the cycle rather than at MAP withdrawal, demonstrating that these treatments did not induce estrus. To determine whether the EB treatment altered endometrial sensitivity to oxytocin and thus the luteolytic cascade, multiparous pre-synchronized cows received 5 mg of EB followed 6 hours later with 50 IU of oxytocin (OT; n=9). Eight hours after EB injection, endometrial fragments were collected from the cows on days 4, 13 and 17 of the estrous cycle and COX-2 gene expression was measured by PCR. EB increased COX-2 mRNA levels only on day 17 of the estrous cycle (P<0.05). In conclusion, MAP alone or associated with EB is able to suppress bovine follicular growth. However, EB in the presence of MAP is not efficient to induce luteolysis in cows when injected on day 8 of the estrous cycle.

Modification of Pineal Ultrastructure by Exogenous Hormones

1967 ◽  
Vol 25 ◽  
pp. 170-171
Author(s):  
R. A. Turner ◽  
A. E. Rodin ◽  
D. K. Roberts
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Rough Endoplasmic Reticulum ◽  
Estradiol Benzoate ◽  
Female Rats ◽  
List Type ◽  
Type Number ◽  
Pregnant Rats ◽  
Gonadal Atrophy ◽  
Pineal Ultrastructure

There have been many reports which establish a relationship between the pineal and sexual structures, including gonadal hypertrophy after pinealectomy, and gonadal atrophy after injection of pineal homogenates or of melatonin. In order to further delineate this relationship the pineals from 5 groups of female rats were studied by electron microscopy:ControlsPregnant ratsAfter 4 weekly injections of 0.1 mg. estradiol benzoate.After 8 daily injections of 150 mcgm. melatonin (pineal hormone).After 8 daily injections of 3 mg. serotonin (melatonin precursor).No ultrastructural differences were evident between the control, and the pregnancy and melatonin groups. However, the estradiol injected animals exhibited a marked increase in the amount and size of rough endoplasmic reticulum within the pineal cells.

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