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Corre PHC, Mainwaring JM, Peralta KKZ, Lokman PM, Porteous R, Wibowo E. Low dose of propyl-pyrazole-triol, an agonist of estrogen receptor alpha, administration stimulates the Coolidge effect in fadrozole-treated male rats. Horm Behav 2024; 161:105520. [PMID: 38447331 DOI: 10.1016/j.yhbeh.2024.105520] [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: 10/03/2023] [Revised: 02/22/2024] [Accepted: 02/23/2024] [Indexed: 03/08/2024]
Abstract
Estrogen receptor (ER) α is involved in male sexual function. Here, we aim to investigate how ERα activation influences sexual satiety and the Coolidge effect (i.e., when a rat, that has reached sexual satiety, experiences an increased arousal after exposure to a novel sexual partner) in estrogen-deprived male rats. Male rats (8 per group) were treated daily for 29 days with either saline (Control group) or fadrozole dissolved in saline (1 mg/kg/day) 1 h before mating. On Days 13 and 29, rats treated with fadrozole received either no additional treatment (fadrozole group) or a single injection of propyl-pyrazole-triol (ERα-agonist group, dissolved in sesame oil, 1 mg/kg). Rats mated until reaching sexual satiety on Days 13 and 29. In these sessions, the Control group displayed higher frequency of intromission and ejaculation than the other groups. The ERα-agonist group mounted more frequently but reached sexual satiety sooner than the Control group. On Day 29, when exposed to a new sexual partner, the fadrozole-treated rats were less likely to display intromission than the other groups, or ejaculation than the Control group, or mounting than the ERα-agonist group. The Control group showed more ejaculatory behavior and shorter ejaculation latency than the other groups. Body weights, testosterone levels, estradiol levels, and ERα-immunoreactive cell counts in brain regions for sexual behavior were comparable between groups after 29 days of treatments. Our data suggest that estrogen helps regulate sexual satiety and the Coolidge effect in male rats.
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Affiliation(s)
- P Hanna C Corre
- Department of Anatomy, University of Otago, Dunedin 9016, New Zealand.
| | | | - K Kenn Z Peralta
- Department of Anatomy, University of Otago, Dunedin 9016, New Zealand.
| | - P Mark Lokman
- Department of Zoology, University of Otago, Dunedin 9016, New Zealand.
| | - Robert Porteous
- Otago Micro and Nanoscale Imaging, University of Otago, Dunedin 9016, New Zealand.
| | - Erik Wibowo
- Department of Anatomy, University of Otago, Dunedin 9016, New Zealand.
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2
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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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3
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Pereira LDS, Gobbo DR, Ferreira JGP, Horta-Junior JDADCE, Sá SI, Bittencourt JC. Effects of ovariectomy on inputs from the medial preoptic area to the ventromedial nucleus of the hypothalamus of young adult rats. J Anat 2021; 238:467-479. [PMID: 32914872 PMCID: PMC7812137 DOI: 10.1111/joa.13304] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 08/05/2020] [Accepted: 08/06/2020] [Indexed: 02/03/2023] Open
Abstract
Puberty is an important phase of development when the neural circuit organization is transformed by sexual hormones, inducing sexual dimorphism in adult behavioural responses. The principal brain area responsible for the control of the receptive component of female sexual behaviour is the ventrolateral division of the ventromedial nucleus of the hypothalamus (VMHvl), which is known for its dependency on ovarian hormones. Inputs to the VMHvl originating from the medial preoptic nucleus (MPN) are responsible for conveying essential information that will trigger such behaviour. Here, we investigated the pattern of the projection of the MPN to the VMHvl in rats ovariectomized at the onset of puberty. Sprague Dawley rats were ovariectomized (OVX) at puberty and then subjected to iontophoretic injections of the neuronal anterograde tracer Phaseolus vulgaris leucoagglutinin into the MPN once they reached 90 days of age. This study analysed the connectivity pattern established between the MPN and the VMH that is involved in the neuronal circuit responsible for female sexual behaviour in control and OVX rats. The data show the changes in the organization of the connections observed in the OVX adult rats that displayed a reduced axonal length for the MPN fibres reaching the VMHvl, suggesting that peripubertal ovarian hormones are relevant to the organization of MPN connections with structures involved in the promotion of female sexual behaviour.
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Affiliation(s)
- Laís da Silva Pereira
- Laboratorio de Neuroanatomia Quimica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, São Paulo, Brazil
| | - Denise Ribeiro Gobbo
- Laboratorio de Neuroanatomia Quimica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, São Paulo, Brazil
| | | | | | - Susana Isabel Sá
- Unit of Anatomy, Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal
- Faculty of Medicine, CINTESIS, Centre for Health Technology and Services Research, University of Porto, Porto, Portugal
| | - Jackson Cioni Bittencourt
- Laboratorio de Neuroanatomia Quimica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, São Paulo, Brazil
- Nucleo de Neurociencias e Comportamento, Instituto de Psicologia, Universidade de Sao Paulo, Sao Paulo, Brazil
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Vaillant C, Gueguen MM, Feat J, Charlier TD, Coumailleau P, Kah O, Brion F, Pellegrini E. Neurodevelopmental effects of natural and synthetic ligands of estrogen and progesterone receptors in zebrafish eleutheroembryos. Gen Comp Endocrinol 2020; 288:113345. [PMID: 31812531 DOI: 10.1016/j.ygcen.2019.113345] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 11/03/2019] [Accepted: 11/26/2019] [Indexed: 12/31/2022]
Abstract
Natural and synthetic estrogens and progestins are widely used in human and veterinary medicine and are detected in waste and surface waters. Our previous studies have clearly shown that a number of these substances targets the brain to induce the estrogen-regulated brain aromatase expression but the consequences on brain development remain virtually unexplored. The aim of the present study was therefore to investigate the effect of estradiol (E2), progesterone (P4) and norethindrone (NOR), a 19-nortestosterone progestin, on zebrafish larval neurogenesis. We first demonstrated using real-time quantitative PCR that nuclear estrogen and progesterone receptor brain expression is impacted by E2, P4 and NOR. We brought evidence that brain proliferative and apoptotic activities were differentially affected depending on the steroidal hormone studied, the concentration of steroids and the region investigated. Our findings demonstrate for the first time that steroid compounds released in aquatic environment have the capacity to disrupt key cellular events involved in brain development in zebrafish embryos further questioning the short- and long-term consequences of this disruption on the physiology and behavior of organisms.
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Affiliation(s)
- Colette Vaillant
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, F-35000 Rennes, France
| | - Marie-Madeleine Gueguen
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, F-35000 Rennes, France
| | - Justyne Feat
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, F-35000 Rennes, France
| | - Thierry D Charlier
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, F-35000 Rennes, France
| | - Pascal Coumailleau
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, F-35000 Rennes, France
| | - Olivier Kah
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, F-35000 Rennes, France
| | - François Brion
- Institut National de l'Environnement Industriel et des Risques INERIS, Unité d'Ecotoxicologie, 60550, Verneuil-en-Halatte, France
| | - Elisabeth Pellegrini
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, F-35000 Rennes, France.
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5
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Loutchanwoot P, Vortherms T. Effects of puerarin on estrogen-regulated gene expression in gonadotropin-releasing hormone pulse generator of ovariectomized rats. Steroids 2018; 135:54-62. [PMID: 29733861 DOI: 10.1016/j.steroids.2018.05.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 04/28/2018] [Accepted: 05/02/2018] [Indexed: 11/28/2022]
Abstract
Effects of puerarin on the hypothalamic gonadotropin-releasing hormone (GnRH) pulse generator function is investigated, for the first time, in ovariectomized rats at the level of mRNA expression of estrogen-responsive genes, e.g., estrogen receptor (ER), GnRH and its receptor (GnRHR). Rats were treated orally for 90 days either with a soy-free diet containing two different doses of puerarin (low dose of 600 mg/kg and high dose of 3000 mg/kg) or estradiol benzoate (E2B) at either low dose (4.3 mg/kg) or high dose (17.3 mg/kg). Levels of mRNA expression in the medial preoptic area/anterior hypothalamus (MPOA/AH), mediobasal hypothalamus/median eminence (MBH/ME) and adenohypophysis were measured by quantitative TaqMan® real-time RT-PCR. Plasma levels of luteinizing hormone (LH) and prolactin (PRL) were measured by radioimmunoassay. In the MPOA/AH, both puerarin and E2B decreased ERα mRNA levels without any significant changes in ERβ and GnRH mRNA levels. Both puerarin and E2B did not significantly alter the expression levels of ERα, ERβ and GnRHR in the MBH/ME. E2B exerted significant effects on the down-regulation of adenohypophyseal GnRHR mRNA transcripts and serum LH levels. Puerarin did not cause significant changes in pituitary GnRHR mRNA transcripts and serum LH and PRL levels. This is the first study to demonstrate that in ovariectomized rat models of ovarian hormone deprivation, puerarin acted as a weak estrogen-active compound in the hypothalamic GnRH pulse generator through the downregulation of MPOA/AH ERα mRNA expression.
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Affiliation(s)
- Panida Loutchanwoot
- Department of Biology, Faculty of Science, Mahasarakham University, Khamriang Sub-district, Kantarawichai District, Mahasarakham Province 44150, Thailand.
| | - Tina Vortherms
- Department of Endocrinology, Faculty of Medicine, University Medical Center Göttingen, Robert-Koch-Strasse 40, D-37075 Göttingen, Germany
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6
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Effects of tamoxifen on neuronal morphology, connectivity and biochemistry of hypothalamic ventromedial neurons: Impact on the modulators of sexual behavior. Neurobiol Dis 2018; 109:33-43. [DOI: 10.1016/j.nbd.2017.09.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 09/06/2017] [Accepted: 09/21/2017] [Indexed: 12/21/2022] Open
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Payrits M, Sághy É, Cseko K, Pohóczky K, Bölcskei K, Ernszt D, Barabás K, Szolcsányi J, Ábrahám IM, Helyes Z, Szoke É. Estradiol Sensitizes the Transient Receptor Potential Vanilloid 1 Receptor in Pain Responses. Endocrinology 2017; 158:3249-3258. [PMID: 28977586 DOI: 10.1210/en.2017-00101] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 06/29/2017] [Indexed: 11/19/2022]
Abstract
Sex differences exist in chronic pain pathologies, and gonadal estradiol (E2) alters the pain sensation. The nocisensor transient receptor potential vanilloid 1 (TRPV1) receptor plays a critical role in triggering pain. Here we examined the impact of E2 on the function of TRPV1 receptor in mice sensory neurons in vitro and in vivo. Both mechano- and thermonociceptive thresholds of the plantar surface of the paw of female mice were significantly lower in proestrus compared with the estrus phase. These thresholds were higher in ovariectomized (OVX) mice and significantly lower in sham-operated mice in proestrus compared with the sham-operated mice in estrus phase. This difference was absent in TRPV1 receptor-deficient mice. Furthermore, E2 potentiated the TRPV1 receptor activation-induced mechanical hyperalgesia in OVX mice. Long pretreatment (14 hours) with E2 induced a significant increase in TRPV1 receptor messenger RNA expression and abolished the capsaicin-induced TRPV1 receptor desensitization in primary sensory neurons. The short E2 incubation (10 minutes) also prevented the desensitization, which reverted after coadministration of E2 and the tropomyosin-related kinase A (TrkA) receptor inhibitor. Our study provides in vivo and in vitro evidence for E2-induced TRPV1 receptor upregulation and sensitization mediated by TrkAR via E2-induced genomic and nongenomic mechanisms. The sensitization and upregulation of TRPV1 receptor by E2 in sensory neurons may explain the greater pain sensitivity in female mice.
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Affiliation(s)
- Maja Payrits
- Department of Pharmacology and Pharmacotherapy, University of Pécs Medical School, H-7624 Pécs, Hungary
- Janos Szentagothai Research Centre, University of Pécs, H-7624 Pécs, Hungary
| | - Éva Sághy
- Department of Pharmacology and Pharmacotherapy, University of Pécs Medical School, H-7624 Pécs, Hungary
- Janos Szentagothai Research Centre, University of Pécs, H-7624 Pécs, Hungary
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, H-1089, Budapest, Hungary
| | - Kata Cseko
- Department of Pharmacology and Pharmacotherapy, University of Pécs Medical School, H-7624 Pécs, Hungary
- Janos Szentagothai Research Centre, University of Pécs, H-7624 Pécs, Hungary
| | - Krisztina Pohóczky
- Department of Pharmacology and Pharmacotherapy, University of Pécs Medical School, H-7624 Pécs, Hungary
- Janos Szentagothai Research Centre, University of Pécs, H-7624 Pécs, Hungary
| | - Kata Bölcskei
- Department of Pharmacology and Pharmacotherapy, University of Pécs Medical School, H-7624 Pécs, Hungary
- Janos Szentagothai Research Centre, University of Pécs, H-7624 Pécs, Hungary
| | - Dávid Ernszt
- Janos Szentagothai Research Centre, University of Pécs, H-7624 Pécs, Hungary
- Department of Pharmaceutical Biotechnology, University of Pécs, Medical School, H-7624 Pécs, Hungary
| | - Klaudia Barabás
- Janos Szentagothai Research Centre, University of Pécs, H-7624 Pécs, Hungary
- Institute of Physiology, University of Pécs, Medical School, H-7624 Pécs, Hungary
| | - János Szolcsányi
- Department of Pharmacology and Pharmacotherapy, University of Pécs Medical School, H-7624 Pécs, Hungary
- Janos Szentagothai Research Centre, University of Pécs, H-7624 Pécs, Hungary
| | - István M Ábrahám
- Janos Szentagothai Research Centre, University of Pécs, H-7624 Pécs, Hungary
- Institute of Physiology, University of Pécs, Medical School, H-7624 Pécs, Hungary
- MTA-PTE NAP B Molecular Neuroendocrinology Research Group-Hungary, H-7624 Pécs, Hungary
- Centre for Neuroscience, University of Pécs, H-7624 Pécs, Hungary
| | - Zsuzsanna Helyes
- Department of Pharmacology and Pharmacotherapy, University of Pécs Medical School, H-7624 Pécs, Hungary
- Janos Szentagothai Research Centre, University of Pécs, H-7624 Pécs, Hungary
- Centre for Neuroscience, University of Pécs, H-7624 Pécs, Hungary
- MTA-PTE NAP B Chronic Pain Research Group-Hungary, H-7624 Pécs, Hungary
| | - Éva Szoke
- Department of Pharmacology and Pharmacotherapy, University of Pécs Medical School, H-7624 Pécs, Hungary
- Janos Szentagothai Research Centre, University of Pécs, H-7624 Pécs, Hungary
- MTA-PTE NAP B Chronic Pain Research Group-Hungary, H-7624 Pécs, Hungary
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8
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Jacobskind JS, Rosinger ZJ, Zuloaga DG. Hypothalamic-pituitary-adrenal axis responsiveness to methamphetamine is modulated by gonadectomy in males. Brain Res 2017; 1677:74-85. [PMID: 28941573 DOI: 10.1016/j.brainres.2017.09.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 08/18/2017] [Accepted: 09/17/2017] [Indexed: 12/14/2022]
Abstract
Sex differences in patterns of methamphetamine (MA) abuse have been reported with females (humans and rodents) showing an elevated addiction phenotype. Previous findings indicate MA-induced hypothalamic-pituitary-adrenal (HPA) axis activation is also sexually dimorphic with females exhibiting an elevated glucocorticoid release and differential neural activation patterns within HPA axis-associated brain regions. These effects may contribute to sex differences in abuse. To determine the role of gonadal hormones in mediating sex differences in MA-induced glucocorticoids, male and female C57BL/6J mice were gonadectomized or sham-operated, and following recovery, injected with MA (5mg/kg) and sacrificed 60min or 120min later. Blood was collected for corticosterone radioimmunoassay, and brains were used to assess c-Fos, and c-Fos co-localization with glucocorticoid receptor (GR). At 120min after MA injection, corticosterone levels were elevated in females compared to males and gonadectomy in males increased corticosterone to female levels. C-Fos was greater in females than males in the medial preoptic area, bed nucleus of the stria terminalis, basolateral amygdala, and central amygdala. Female gonadectomy had little effect on either corticosterone or c-Fos, while male gonadectomy elevated c-Fos in the central amygdala. Relative to sham males, gonadectomized males also showed decreased c-Fos/GR cell number in the CA3 hippocampal area compared to sham males, indicating a central site for attenuated negative feedback. Together, these findings indicate that androgens regulate MA-induced activation of the HPA axis, potentially by enhancing negative feedback. These sex and gonadal hormone effects on the HPA axis may contribute to sex differences in MA abuse patterns.
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Affiliation(s)
- Jason S Jacobskind
- University at Albany, Department of Psychology, Albany, NY 12222, United States
| | - Zachary J Rosinger
- University at Albany, Department of Psychology, Albany, NY 12222, United States
| | - Damian G Zuloaga
- University at Albany, Department of Psychology, Albany, NY 12222, United States.
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9
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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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10
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Rebouças ECC, Leal S, Silva SM, Sá SI. Changes in the female arcuate nucleus morphology and neurochemistry after chronic ethanol consumption and long-term withdrawal. J Chem Neuroanat 2016; 77:30-40. [PMID: 27154870 DOI: 10.1016/j.jchemneu.2016.05.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 05/02/2016] [Accepted: 05/02/2016] [Indexed: 12/26/2022]
Abstract
Ethanol is a macronutrient whose intake is a form of ingestive behavior, sharing physiological mechanisms with food intake. Chronic ethanol consumption is detrimental to the brain, inducing gender-dependent neuronal damage. The hypothalamic arcuate nucleus (ARN) is a modulator of food intake that expresses feeding-regulatory neuropeptides, such as alpha melanocyte-stimulating hormone (α-MSH) and neuropeptide Y (NPY). Despite its involvement in pathways associated with eating disorders and ethanol abuse, the impact of ethanol consumption and withdrawal in the ARN structure and neurochemistry in females is unknown. We used female rat models of 20% ethanol consumption for six months and of subsequent ethanol withdrawal for two months. Food intake and body weights were measured. ARN morphology was stereologically analyzed to estimate its volume, total number of neurons and total number of neurons expressing NPY, α-MSH, tyrosine hydroxylase (TH) and estrogen receptor alpha (ERα). Ethanol decreased energy intake and body weights. However, it did not change the ARN morphology or the expression of NPY, α-MSH and TH, while increasing ERα expression. Withdrawal induced a significant volume and neuron loss that was accompanied by an increase in NPY expression without affecting α-MSH and TH expression. These findings indicate that the female ARN is more vulnerable to withdrawal than to excess alcohol. The data also support the hypothesis that the same pathways that regulate the expression of NPY and α-MSH in long-term ethanol intake may regulate food intake. The present model of long-term ethanol intake and withdrawal induces new physiological conditions with adaptive responses.
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Affiliation(s)
- Elce C C Rebouças
- Department of Natural Sciences, State University of Southwestern Bahia, Praça Primavera, 40-Bairro Primavera, Itapetinga, BA 45700-000, Brazil; Department of Anatomy, Faculty of Medicine, University of Porto, Al. Prof. Hernâni Monteiro, 4200-319 Porto, Portugal; Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Rua Dr. Plácido da Costa, 4200-450 Porto, Portugal.
| | - Sandra Leal
- Department of Anatomy, Faculty of Medicine, University of Porto, Al. Prof. Hernâni Monteiro, 4200-319 Porto, Portugal; Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Rua Dr. Plácido da Costa, 4200-450 Porto, Portugal; Institute of Research and Advanced Training in Health Sciences and Technologies (IINFACTS), Department of Sciences, Instituto Universitário de Ciências da Saúde (IUCS), CESPU, CRL, R. Central da Gandra 1317, 4585-116 Gandra, Portugal.
| | - Susana M Silva
- Department of Anatomy, Faculty of Medicine, University of Porto, Al. Prof. Hernâni Monteiro, 4200-319 Porto, Portugal; Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Rua Dr. Plácido da Costa, 4200-450 Porto, Portugal.
| | - Susana I Sá
- Department of Anatomy, Faculty of Medicine, University of Porto, Al. Prof. Hernâni Monteiro, 4200-319 Porto, Portugal; Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Rua Dr. Plácido da Costa, 4200-450 Porto, Portugal.
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