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Pinto CA, Fonseca BM, Sá SI. Effects of chronic tamoxifen treatment in female rat sexual behaviour. Heliyon 2022; 8:e12362. [PMID: 36593822 PMCID: PMC9803792 DOI: 10.1016/j.heliyon.2022.e12362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 09/05/2022] [Accepted: 12/07/2022] [Indexed: 12/23/2022] Open
Abstract
The medial preoptic (MPN) and the ventromedial hypothalamic nuclei (VMN) modulate the estrogen receptor (ER)-dependent female sexual behavior, a response that is inhibited by tamoxifen (TAM), a modulator of the steroid receptor activation. With the objective to assess TAM action in the brain areas involved in the modulation sexual cues, an animal model on long-term TAM therapy to intact female rats, was used to mimic the 5-year prophylactic TAM therapy offered to women at higher risk of breast cancer. After three months treatment, female sexual behavior with a stud male rat was evaluated. Upon sacrifice, the brains were removed and the MPN and the ventrolateral division of the VMN were screened for the effects of TAM in the expression of ERα, ERβ and progesterone receptor. Results show that TAM inhibited the receptive component of the female sexual behavior. Even though TAM decreased estrogen and progesterone levels to values similar to the ones of estrous and diestrus rats, the biochemical data failed to demonstrate such possible causation for the behavioral response. In fact, TAM administration induced a constant low level of ovarian hormones that changed the pattern of ER and PR expression as well as receptor co-expression in the brain areas regulating the behavioral response, dissimilar to the ones seen in the cycle phases with the same low hormone levels. Nevertheless, present data suggests that by affecting ER- and/or PR-dependent mechanisms, TAM may modulate the hypothalamus, a region known to participate in several social behaviors.
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Affiliation(s)
- Cláudia A. Pinto
- Unit of Anatomy, Department of Biomedicine, Faculty of Medicine, University of Porto, Al Professor Hernani Monteiro, 4200-319 Porto, Portugal
| | - Bruno M. Fonseca
- UCIBIO, REQUIMTE, Laboratory of Biochemistry, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira nº. 228, 4050-313 Porto, Portugal
| | - Susana I. Sá
- Unit of Anatomy, Department of Biomedicine, Faculty of Medicine, University of Porto, Al Professor Hernani Monteiro, 4200-319 Porto, Portugal,CINTESIS@RISE Unit of Anatomy, Department of Biomedicine, Faculty of Medicine, University of Porto. Al Professor Hernani Monteiro, 4200-319 Porto, Portugal,Corresponding author.
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Kim J, Cha S, Lee MY, Hwang YJ, Yang E, Choi D, Lee SH, Cheon YP. Chronic and Low Dose Exposure to Nonlyphenol or Di(2-Ethylhexyl) Phthalate Alters Cell Proliferation and the Localization of Steroid Hormone Receptors in Uterine Endometria in Mice. Dev Reprod 2019; 23:263-275. [PMID: 31660453 PMCID: PMC6812976 DOI: 10.12717/dr.2019.23.3.263] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Revised: 08/30/2019] [Accepted: 09/19/2019] [Indexed: 02/04/2023]
Abstract
Based on our preliminary results, we examined the possible role of low-dose and
chronic-exposing of the chemicals those are known as endocrine disrupting
chemical (EDC), on the proliferation of uterine endometrium and the localization
of steroid receptors. Immunohistochemical or immunofluorochemical methodology
were employed to evaluate the localization of antigen identified by monoclonal
antibody Ki 67 protein (MKI67), estrogen receptor 1 (ESR1), estrogen receptor 2
(ESR2), and progesterone receptor (PGR). In 133 μg/L and 1,330
μg/L di(2-ethylhexyl) phthalate (DEHP) and 50 μg/L nonylphenol
(NP) groups, the ratio of MKI67 positive stromal cells was significantly
increased but not in 500 μg/L NP group. The ratios of MKI67 positive
glandular and luminal epithelial cells were also changed by the chronic
administration of NP and DEHP in tissue with dose specific manner. ESR1 signals
were localized in nucleus in glandular and luminal epithelia of control group
but its localization was mainly in cytoplasm in DEHP and NP administered groups.
On the other hand, it was decreased at nucleus of stromal cells in 1,330
μg/L DEHP group. The colocalization patterns of these nuclear receptors
were also modified by the administration of these chemicals. Such a tissue
specific and dose specific localization of ESR2 and PGR were detected as ESR1 in
all the uterine endometrial tissues. These results show that the chronic
lows-dose exposing of NP or DEHP modify the localization and colocalization of
ESRs and PGR, and of the proliferation patterns of the endometrial tissues.
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Affiliation(s)
- Juhye Kim
- Division of Developmental Biology and Physiology, Dept. of Biotechnology, Sungshin University, Seoul 02844, Korea
| | - Sunyeong Cha
- Division of Developmental Biology and Physiology, Dept. of Biotechnology, Sungshin University, Seoul 02844, Korea
| | - Min Young Lee
- Division of Developmental Biology and Physiology, Dept. of Biotechnology, Sungshin University, Seoul 02844, Korea
| | - Yeon Jeong Hwang
- Division of Developmental Biology and Physiology, Dept. of Biotechnology, Sungshin University, Seoul 02844, Korea
| | - Eunhyeok Yang
- Division of Developmental Biology and Physiology, Dept. of Biotechnology, Sungshin University, Seoul 02844, Korea
| | - Donchan Choi
- Dept. of Life Science, College of Environmental Sciences, Yong-In University, Yongin 17092, Korea
| | - Sung-Ho Lee
- Dept. of Biotechnology, Sangmyung University, Seoul 03016, Korea
| | - Yong-Pil Cheon
- Division of Developmental Biology and Physiology, Dept. of Biotechnology, Sungshin University, Seoul 02844, Korea
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Tominna R, Chokr S, Feri M, Chuon T, Sinchak K. Plasma membrane G protein-coupled estrogen receptor 1 (GPER) mediates rapid estradiol facilitation of sexual receptivity through the orphanin-FQ-ORL-1 system in estradiol primed female rats. Horm Behav 2019; 112:89-99. [PMID: 30981690 DOI: 10.1016/j.yhbeh.2019.04.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2018] [Revised: 03/26/2019] [Accepted: 04/08/2019] [Indexed: 11/29/2022]
Abstract
In estradiol-primed nonreceptive ovariectomized rats, activation of G protein-coupled estrogen receptor 1 (GPER) in the arcuate nucleus of the hypothalamus (ARH) rapidly facilitates sexual receptivity (lordosis). Estradiol priming activates ARH β-endorphin (β-END) neurons that then activate medial preoptic (MPN) μ-opioid receptors (MOP) to inhibit lordosis. ARH infusion of non-esterified 17β-estradiol (E2) 47.5 h after 17β-estradiol benzoate (2 μg EB) priming deactivates MPN MOP and rapidly facilitates lordosis within 30 min via activation of GPER. Since it was unclear where GPERs were located in the neuron, we tested the hypothesis that GPER signaling is initiated at the plasma membrane. Membrane impermeable estradiol (17β-estradiol conjugated to biotin; E-Biotin) infused into the ARH of EB primed rats facilitated lordosis within 30 min, and MPN MOP was deactivated. These actions were blocked by pretreating with GPER antagonist, G-15. Further, we used cell fractionation and western blot techniques to demonstrate that GPER is expressed both in plasma membrane and cytosolic ARH fractions. In previous studies, the orphanin FQ/nociceptin-opioid receptor-like receptor-1 (OFQ/N-ORL-1) system mediated estradiol-only facilitation of lordosis. Therefore, we tested whether the OFQ/N-ORL-1 system mediates E-Biotin-GPER facilitation of lordosis. Pretreatment of UFP-101, an ORL-1 selective antagonist, blocked the facilitation of lordosis and deactivation of MPN MOP by ARH infusion of E-Biotin. Double-label immunohistochemistry revealed that GPER is expressed within approximately 70% of OFQ/N neurons. These data indicate that membrane GPER mediates the E2/E-Biotin facilitation of lordosis by inducing OFQ/N neurotransmission, which inhibits β-END neurotransmission to reduce MPN MOP activation.
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Affiliation(s)
- Reema Tominna
- Department of Biological Sciences, California State University, Long Beach, Long Beach, CA, United States of America
| | - Sima Chokr
- Department of Biological Sciences, California State University, Long Beach, Long Beach, CA, United States of America
| | - Micah Feri
- Department of Biological Sciences, California State University, Long Beach, Long Beach, CA, United States of America
| | - Timbora Chuon
- Department of Biological Sciences, California State University, Long Beach, Long Beach, CA, United States of America
| | - Kevin Sinchak
- Department of Biological Sciences, California State University, Long Beach, Long Beach, CA, United States of America.
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Sá SI, Maia J, Bhowmick N, Silva SM, Silva A, Correia-da-Silva G, Teixeira N, Fonseca BM. Uterine histopathological changes induced by acute administration of tamoxifen and its modulation by sex steroid hormones. Toxicol Appl Pharmacol 2019; 363:88-97. [DOI: 10.1016/j.taap.2018.11.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 11/07/2018] [Accepted: 11/28/2018] [Indexed: 11/24/2022]
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Micevych PE, Sinchak K. Extranuclear signaling by ovarian steroids in the regulation of sexual receptivity. Horm Behav 2018; 104:4-14. [PMID: 29753716 PMCID: PMC6240501 DOI: 10.1016/j.yhbeh.2018.05.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 05/02/2018] [Accepted: 05/03/2018] [Indexed: 01/06/2023]
Affiliation(s)
- Paul E Micevych
- Dept of Neurobiology, David Geffen School of Medicine at UCLA, Laboratory of Neuroendocrinology of the UCLA Brain Research Institute, United States
| | - Kevin Sinchak
- Dept of Biological Sciences, California State University, Long Beach, United States.
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Büdefeld T, Spanic T, Vrecl M, Majdic G. Fezf1 is a novel regulator of female sex behavior in mice. Horm Behav 2018; 97:94-101. [PMID: 29080672 DOI: 10.1016/j.yhbeh.2017.10.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 09/26/2017] [Accepted: 10/24/2017] [Indexed: 11/24/2022]
Abstract
UNLABELLED Female sexual behavior is a complex process regulated by multiple brain circuits and influenced by sex steroid hormones acting in the brain. Several regions in the hypothalamus have been implicated in the regulation of female sexual behavior although a complete circuitry involved in female sexual behavior is not understood. Fez family zinc finger 1 (Fezf1) gene is a brain specific gene that has been mostly studied in the context of olfactory development, although in a recent study, FEZF1 has been identified as one of the genes responsible for the development of Kallman syndrome. In the present study, we utilized shRNA approach to downregulate Fezf1 in the ventromedial nucleus of the hypothalamus (VMN) with the aim to explore the role of this gene. Adult female mice were stereotaxically injected with lentiviral vectors encoding shRNA against Fezf1 gene. Mice injected with shRNA against Fezf1 had significantly reduced female sexual behavior, presumably due to the downregulation of estrogen receptor alpha (ERα), as the number of ERα-immunoreactive cells in the VMN of Fezf1 mice was significantly lower in comparison to controls. However, no effect on body weight or physical activity was observed in mice with downregulated Fezf1, suggesting that the role of Fezf1 in the VMN is limited to the regulation of sexual behavior. SIGNIFICANCE STATEMENT Fezf1 gene has been identified in the present study as a regulator of female sexual behavior in mice. Regulation of the female sexual behavior could be through the regulation of estrogen receptor alpha expression in the ventromedial nucleus of the hypothalamus, as the expression of this receptor was reduced in mice with downregulated Fezf1. As expression of Fezf1 is very specific in the brain, this gene could present a potential target for the development of novel drugs regulating hypoactive sexual desire disorder in women, if similar function of FEZF1 will be confirmed in humans.
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Affiliation(s)
- Tomaz Büdefeld
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbiceva 60, 1000 Ljubljana, Slovenia
| | - Tanja Spanic
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbiceva 60, 1000 Ljubljana, Slovenia
| | - Milka Vrecl
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbiceva 60, 1000 Ljubljana, Slovenia
| | - Gregor Majdic
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbiceva 60, 1000 Ljubljana, Slovenia; Institute of Physiology, Medical School, University of Maribor, Maribor, Slovenia.
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Micevych PE, Mermelstein PG, Sinchak K. Estradiol Membrane-Initiated Signaling in the Brain Mediates Reproduction. Trends Neurosci 2017; 40:654-666. [PMID: 28969926 DOI: 10.1016/j.tins.2017.09.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 08/28/2017] [Accepted: 09/10/2017] [Indexed: 12/21/2022]
Abstract
Over the past few years our understanding of estrogen signaling in the brain has expanded rapidly. Estrogens are synthesized in the periphery and in the brain, acting on multiple receptors to regulate gene transcription, neural function, and behavior. Various estrogen-sensitive signaling pathways often operate in concert within the same cell, increasing the complexity of the system. In females, estrogen concentrations fluctuate over the estrous/menstrual cycle, dynamically modulating estrogen receptor (ER) expression, activity, and trafficking. These dynamic changes influence multiple behaviors but are particularly important for reproduction. Using the female rodent model, we review our current understanding of estradiol signaling in the regulation of sexual receptivity.
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Affiliation(s)
- Paul E Micevych
- Department of Neurobiology, David Geffen School of Medicine at the University of California Los Angeles (UCLA), and Laboratory of Neuroendocrinology of the UCLA Brain Research Institute, Los Angeles, CA 90095, USA.
| | - Paul G Mermelstein
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
| | - Kevin Sinchak
- Department of Biological Sciences, California State University, Long Beach, Long Beach, CA 90840, USA
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Novel oestrogen receptor β-selective ligand reduces obesity and depressive-like behaviour in ovariectomized mice. Sci Rep 2017; 7:4663. [PMID: 28680060 PMCID: PMC5498485 DOI: 10.1038/s41598-017-04946-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 06/07/2017] [Indexed: 12/11/2022] Open
Abstract
Hormonal changes due to menopause can cause various health problems including weight gain and depressive symptoms. Multiple lines of evidence indicate that oestrogen receptors (ERs) play a major role in postmenopausal obesity and depression. However, little is known regarding the ER subtype-specific effects on obesity and depressive symptoms. To delineate potential effects of ERβ activation in postmenopausal women, we investigated the effects of a novel oestrogen receptor β-selective ligand (C-1) in ovariectomized mice. Uterine weight, depressive behaviour, and weight gain were examined in sham-operated control mice and ovariectomized mice administered placebo, C-1, or 17β-oestradiol (E2). Administration of C-1 or E2 reduced body weight gain and depressive-like behaviour in ovariectomized mice, as assessed by the forced swim test. In addition, administration of E2 to ovariectomized mice increased uterine weight, but administration of C-1 did not result in a significant increase in uterine weight. These results suggest that the selective activation of ERβ in ovariectomized mice may have protective effects against obesity and depressive-like behaviour without causing an increase in uterine weight. The present findings raise the possibility of the application of ERβ-ligands such as C-1 as a novel treatment for obesity and depression in postmenopausal women.
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Sá SI, Fonseca BM. Dynamics of progesterone and estrogen receptor alpha in the ventromedial hypothalamus. J Endocrinol 2017; 233:197-207. [PMID: 28283583 DOI: 10.1530/joe-16-0663] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 03/10/2017] [Indexed: 12/28/2022]
Abstract
Cyclic fluctuations of estradiol and progesterone in females influence neuronal activity in the ventrolateral division of the ventromedial hypothalamic nucleus (VMNvl), through the activation of progesterone receptors (PRs) and estrogen receptors (ERs). The expression of ER and PR in the VMNvl is influenced by their cognate ligands and is a central upstream trigger in the pathway of VMNvl-dependent modulation of endocrine responses. By studying the role played by estradiol and progesterone in PR and ERa expression in the VMNvl along the estrous cycle and how the two receptors interact in the same neuron, we aim to evaluate the synergistic action of both ovarian hormones in the regulation of VMNvl activity. In animals at all phases of the estrous cycle, the number of VMN neurons expressing PR or ERa was estimated by stereological methods, and the percentage, and rostro-caudal distribution, of neurons simultaneously expressing both receptors was determined. The highest number of PR-immunoreactive neurons was seen at proestrus, and of ERa-immunoreactive neurons was seen at proestrus and metestrus. The ERa/PR co-localization is increased at caudal levels. Approximately half the neurons expressing PR co-express ERa, a proportion that stays constant along the estrous cycle. The percentage of ERa neurons co-expressing PR changes from 60% at proestrus to 40% at metestrus. Fluctuations in circulating ovarian hormone levels promote coordinated changes in PR and ERa expression and co-localization. This may be an important mechanism in the regulation of input relayed by the VMNvl, allowing a precise modulation of endocrine responses.
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Affiliation(s)
- Susana I Sá
- Department of BiomedicineUnit of Anatomy, Faculty of Medicine, University of Porto, Porto, Portugal
- Faculty of MedicineCenter for Health Technology and Services Research (CINTESIS), University of Porto, Porto, Portugal
| | - Bruno M Fonseca
- UCIBIOREQUIMTE, Department of Biological Sciences, Laboratory of Biochemistry, Faculty of Pharmacy, University of Porto, Porto, Portugal
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Estrogen Modulates ubc9 Expression and Synaptic Redistribution in the Brain of APP/PS1 Mice and Cortical Neurons. J Mol Neurosci 2017; 61:436-448. [DOI: 10.1007/s12031-017-0884-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 01/09/2017] [Indexed: 12/26/2022]
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Affiliation(s)
- Gad Rennert
- Clalit National Cancer Control Center and Department of Community Medicine and Epidemiology, Carmel Medical Center and B. Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
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Lai YJ, Yu D, Zhang JH, Chen GJ. Cooperation of Genomic and Rapid Nongenomic Actions of Estrogens in Synaptic Plasticity. Mol Neurobiol 2016; 54:4113-4126. [PMID: 27324789 PMCID: PMC5509832 DOI: 10.1007/s12035-016-9979-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 06/14/2016] [Indexed: 12/23/2022]
Abstract
Neuroplasticity refers to the changes in the molecular and cellular processes of neural circuits that occur in response to environmental experiences. Clinical and experimental studies have increasingly shown that estrogens participate in the neuroplasticity involved in cognition, behavior, and memory. It is generally accepted that estrogens exert their effects through genomic actions that occur over a period of hours to days. However, emerging evidence indicates that estrogens also rapidly influence the neural circuitry through nongenomic actions. In this review, we provide an overview of the genomic and nongenomic actions of estrogens and discuss how these actions may cooperate in synaptic plasticity. We then summarize the role of epigenetic modifications, synaptic protein synthesis, and posttranslational modifications, and the splice variants of estrogen receptors in the complicated network of estrogens. The combination of genomic and nongenomic mechanisms endows estrogens with considerable diversity in modulating neural functions including synaptic plasticity.
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Affiliation(s)
- Yu-Jie Lai
- Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing, 400016, China
- Department of Neurology, Affiliated Haikou Hospital of Xiangya Medical College of Central South University, Haikou Municipal Hospital, Haikou, Hainan, 570208, China
| | - Dan Yu
- Department of Neurology, Affiliated Haikou Hospital of Xiangya Medical College of Central South University, Haikou Municipal Hospital, Haikou, Hainan, 570208, China
| | - John H Zhang
- Department of Anesthesiology, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA
| | - Guo-Jun Chen
- Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing, 400016, China.
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Sá SI, Fonseca BM, Teixeira N, Madeira MD. Induction and subcellular redistribution of progesterone receptor A and B by tamoxifen in the hypothalamic ventromedial neurons of young adult female Wistar rats. Mol Cell Endocrinol 2016; 420:1-10. [PMID: 26597778 DOI: 10.1016/j.mce.2015.11.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 10/11/2015] [Accepted: 11/11/2015] [Indexed: 11/22/2022]
Abstract
The ventrolateral division of the hypothalamic ventromedial nucleus (VMNvl) is a brain center for estrogen-dependent triggering of female sexual behavior upon progesterone receptor (PR) activation. We examined the agonistic and antagonistic actions of tamoxifen in this nucleus by analyzing its effects on the total number of PR-immunoreactive neurons, PR mRNA and protein levels, and subcellular location of PRs in ovariectomized Wistar rats. The results show that tamoxifen has no agonistic action in the number of PR-immunoreactive neurons, but increases PR expression and labeling in the nucleus and cytoplasm of VMNvl neurons that constitutively express PRs. As an antagonist, tamoxifen partially inhibited the estradiol-dependent increase in the number of PR-immunoreactive neurons and in PR mRNA and protein levels, without interfering with the subcellular location of the protein. We suggest that tamoxifen influence on PR expression in the VMNvl critically depends on the presence or absence of estradiol.
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Affiliation(s)
- Susana I Sá
- Department of Anatomy, Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, 4200-319 Porto, Portugal; CINTESIS, Centro de Investigação em Tecnologias e Serviços de Saúde Faculty of Medicine, University of Porto, Rua Dr. Plácido da Costa, 4200-450 Porto, Portugal.
| | - Bruno M Fonseca
- UCIBIO, REQUIMTE, Laboratory of Biochemistry, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, n° 228, 4050-313 Porto, Portugal.
| | - Natércia Teixeira
- UCIBIO, REQUIMTE, Laboratory of Biochemistry, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, n° 228, 4050-313 Porto, Portugal.
| | - M Dulce Madeira
- Department of Anatomy, Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, 4200-319 Porto, Portugal; CINTESIS, Centro de Investigação em Tecnologias e Serviços de Saúde Faculty of Medicine, University of Porto, Rua Dr. Plácido da Costa, 4200-450 Porto, Portugal.
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