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1.
Cell ; 163(2): 493-505, 2015 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-26435106

RESUMO

As a basic functional unit in neural circuits, each neuron integrates input signals from hundreds to thousands of synapses. Knowledge of the synaptic input fields of individual neurons, including the identity, strength, and location of each synapse, is essential for understanding how neurons compute. Here, we developed a volumetric super-resolution reconstruction platform for large-volume imaging and automated segmentation of neurons and synapses with molecular identity information. We used this platform to map inhibitory synaptic input fields of On-Off direction-selective ganglion cells (On-Off DSGCs), which are important for computing visual motion direction in the mouse retina. The reconstructions of On-Off DSGCs showed a GABAergic, receptor subtype-specific input field for generating direction selective responses without significant glycinergic inputs for mediating monosynaptic crossover inhibition. These results demonstrate unique capabilities of this super-resolution platform for interrogating neural circuitry.


Assuntos
Neurônios/citologia , Imagem Óptica/métodos , Sinapses/metabolismo , Animais , Encéfalo/citologia , Proteínas de Transporte , Imuno-Histoquímica , Proteínas de Membrana , Camundongos , Rede Nervosa , Vias Neurais , Receptores de GABA/metabolismo , Receptores de Glicina/metabolismo , Células Ganglionares da Retina/metabolismo , Neurônios Retinianos/metabolismo
2.
Proc Natl Acad Sci U S A ; 116(14): 7071-7076, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30890637

RESUMO

Parvalbumin-positive (PV+) interneurons play a pivotal role in orchestrating windows of experience-dependent brain plasticity during development. Critical period closure is marked by the condensation of a perineuronal net (PNN) tightly enwrapping subsets of PV+ neurons, both acting as a molecular brake on plasticity and maintaining mature PV+ cell signaling. As much of the molecular organization of PNNs exists at length scales near or below the diffraction limit of light microscopy, we developed a superresolution imaging and analysis platform to visualize the structural organization of PNNs and the synaptic inputs perforating them in primary visual cortex. We identified a structural trajectory of PNN maturation featuring a range of net structures, which was accompanied by an increase in Synaptotagmin-2 (Syt2) signals on PV+ cells suggestive of increased inhibitory input between PV+ neurons. The same structural trajectory was followed by PNNs both during normal development and under conditions of critical period delay by total sensory deprivation or critical period acceleration by deletion of MeCP2, the causative gene for Rett syndrome, despite shifted maturation levels under these perturbations. Notably, superresolution imaging further revealed a decrease in Syt2 signals alongside an increase in vesicular glutamate transporter-2 signals on PV+ cells in MeCP2-deficient animals, suggesting weaker recurrent inhibitory input between PV+ neurons and stronger thalamocortical excitatory inputs onto PV+ cells. These results imply a latent imbalanced circuit signature that might promote cortical silencing in Rett syndrome before the functional regression of vision.


Assuntos
Proteína 2 de Ligação a Metil-CpG/metabolismo , Rede Nervosa/metabolismo , Plasticidade Neuronal , Síndrome de Rett/metabolismo , Sinapses/metabolismo , Sinaptotagmina II/metabolismo , Córtex Visual/metabolismo , Animais , Masculino , Proteína 2 de Ligação a Metil-CpG/genética , Camundongos , Rede Nervosa/diagnóstico por imagem , Síndrome de Rett/diagnóstico por imagem , Síndrome de Rett/genética , Sinapses/genética , Sinaptotagmina II/genética , Córtex Visual/diagnóstico por imagem
5.
World J Urol ; 34(4): 561-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26253654

RESUMO

PURPOSE: Renal cell carcinoma (RCC) is the most common cancer of kidney. Evidences have shown that RCC is sensitive to various immunotherapies. Tim-3 plays a role in suppressing Th1-mediated immune responses. However, no study has yet examined the effect of Tim-3 on tumor infiltrating lymphocytes (TILs) in RCC. METHODS: We investigated the expression and function of Tim-3 on TIL CD4+ T cells and TIL CD8+ T cells from 30 RCC patients. RESULTS: Levels of Tim-3 were significantly increased on both TIL CD4+ T cells and TIL CD8+ T cells and were associated with higher stages of the cancer. Also, GATA-3 and interferon gamma (IFN-γ) were down-regulated, whereas T-bet was up-regulated in TIL Tim-3+ T cells, indicating that Tim-3 expression defined a population of dysfunctional TIL Th1/Tc1 cells. Mechanism analyses showed that TIL Tim-3-expressing CD8+ T cells exhibited impaired Stat5 and p38 signaling pathway. Blocking the Tim-3 pathway restored cell proliferation and increased IFN-γ production in TIL CD4+ and CD8+ T cells of RCC. CONCLUSIONS: These results suggest that Tim-3 may be used as a novel target for increasing immune responses in RCC tumor microenvironment.


Assuntos
Carcinoma de Células Renais/genética , Regulação Neoplásica da Expressão Gênica , Receptor Celular 2 do Vírus da Hepatite A/genética , Neoplasias Renais/genética , Rim/patologia , Linfócitos do Interstício Tumoral/patologia , RNA Neoplásico/genética , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/metabolismo , Proliferação de Células , Feminino , Citometria de Fluxo , Receptor Celular 2 do Vírus da Hepatite A/biossíntese , Humanos , Rim/metabolismo , Neoplasias Renais/diagnóstico , Neoplasias Renais/metabolismo , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase , Prognóstico
6.
Rev Med Suisse ; 11(492): 1986, 1988-92, 2015 Oct 28.
Artigo em Francês | MEDLINE | ID: mdl-26672176

RESUMO

Although patients' fertility is diminished in the period of perimenopause, they still need efficient contraception. Thorough knowledge of the physiological changes occuring during this period of transition is essential in order to provide optimal care. Until the age of 50, no contraceptive method is specifically considered unsuitable due to age alone. The choice of contraceptive needs to be adapted to the patient, assessing the individual risk factors and favouring the potential non-contraceptive advantages of the method selected. Long-term contraceptive methods (e.g., the copper intrauterine device (IUD), the Mirena IUD or a subcutaneous implant) offer an excellent solution on both levels.


Assuntos
Anticoncepção/métodos , Anticoncepcionais/administração & dosagem , Perimenopausa/fisiologia , Fatores Etários , Feminino , Humanos , Dispositivos Intrauterinos , Pessoa de Meia-Idade , Fatores de Risco
7.
Rev Med Suisse ; 11(486): 1691-5, 2015 Sep 16.
Artigo em Francês | MEDLINE | ID: mdl-26591078

RESUMO

Most clinicians avoid discussing sexuality with patients with severe mental disorders. Sexual disturbances can be related to medication, to psychological issues such as self-stigma and anhedonia, and to the social context. We studied desire and sexual practices in women suffering from schizophrenia, in comparison with healthy women. Contrary to previous research, women with schizophrenia featured dyadic and individual desire similar to women of comparable age. Yet, only half of women with psychosis had sexual practice, either alone or with a partner. They were less satisfied with their activity, both in terms of function and psychological issues such as sexual self-esteem. This finding underscores the stigmatization these women suffer from, which prevents the opportunity of a possible improvement in this important interpersonal domain.


Assuntos
Libido/fisiologia , Transtornos Psicóticos , Comportamento Sexual , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Transtornos Psicóticos/fisiopatologia , Transtornos Psicóticos/psicologia , Comportamento Sexual/psicologia , Disfunções Sexuais Psicogênicas/psicologia , Sexualidade/psicologia , Adulto Jovem
8.
Clin Transplant ; 28(11): 1279-86, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25203694

RESUMO

Although recipient body mass index (BMI) and age are known risk factors for mortality after heart transplantation, how they interact to influence survival is unknown. Our study utilized the UNOS registry from 1997 to 2012 to define the interaction between BMI and age and its impact on survival after heart transplantation. Recipients were stratified by BMI: underweight (<18.5), normal weight (18.5-24.99), overweight (25-29.99), and either moderate (30-34.99), severe (35-39.99), or very severe (≥40) obesity. Recipients were secondarily stratified based on age: 18-40 (younger recipients), 40-65 (reference group), and ≥65 (advanced age recipients). Among younger recipients, being underweight was associated with improved adjusted survival (HR 0.902; p = 0.010) while higher mortality was seen in younger overweight recipients (HR 1.260; p = 0.005). However, no differences in adjusted survival were appreciated in underweight and overweight advanced age recipients. Obesity (BMI ≥ 30) was associated with increased adjusted mortality in normal age recipients (HR 1.152; p = 0.021) and even more so with young (HR 1.576; p < 0.001) and advanced age recipients (HR 1.292; p = 0.001). These results demonstrate that BMI and age interact to impact survival as age modifies BMI-mortality curves, particularly with younger and advanced age recipients.


Assuntos
Fatores Etários , Índice de Massa Corporal , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/cirurgia , Transplante de Coração/mortalidade , Adulto , Idoso , Bases de Dados Factuais , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida
9.
Andrologia ; 46(6): 703-6, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23808476

RESUMO

We report on a case of a man with familial, X-linked, partial androgen insensitivity, in whom a new point mutation in the androgen receptor (AR) ligand-binding domain (causing a valine-to-alanine substitution at codon 686) was identified. High-dose prolonged testosterone therapy resulted in marked progression in patient's appearance and great improvement in sperm count and characteristics. In combination with intracytoplasmic microinjection, treatment resulted in fertility. This is believed to be the first report of such a case. This case supports high-dose testosterone therapeutic trial in this condition. Furthermore, it underscores the possibility of achieving fertility with current endocrine and assisted reproduction modalities, making some of these X-linked AR mutations paternally transmissible.


Assuntos
Síndrome de Resistência a Andrógenos/tratamento farmacológico , Síndrome de Resistência a Andrógenos/genética , Mutação Puntual , Receptores Androgênicos/genética , Testosterona/uso terapêutico , Adulto , Substituição de Aminoácidos , Síndrome de Resistência a Andrógenos/patologia , Feminino , Humanos , Recém-Nascido , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Infertilidade Masculina/terapia , Masculino , Gravidez , Análise do Sêmen , Contagem de Espermatozoides , Injeções de Esperma Intracitoplásmicas , Testosterona/administração & dosagem
10.
J Card Surg ; 29(5): 723-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25041692

RESUMO

BACKGROUND: Data are limited regarding the influence of donor age on outcomes after heart transplantation. We sought to determine if advanced donor age is associated with differences in survival after heart transplantation and how this compares to waitlist survival. METHODS: All adult heart transplants from 2000 to 2012 were identified using the United Network for Organ Sharing database. Donors were stratified into four age groups: 18-39 (reference group), 40-49, 50-54, and 55 and above. Propensity scoring was used to compare status IA waitlist patients who did not undergo transplantation with IA recipients who received hearts from advanced age donors. The primary outcome of interest was recipient survival and this was analyzed with multivariate Cox regression analysis and the Kaplan-Meier method. RESULTS: A total of 22,960 adult heart transplant recipients were identified. Recipients of hearts from all three older donor groups had significantly increased risk of mortality (HR, 1.187-1.426, all p < 0.001) compared to recipients from donors age 18 to 39. Additionally, propensity-matched status IA patients managed medically without transplantation had significantly worse adjusted survival than status IA recipients who received hearts from older donors age ≥55 (HR, 1.362, p < 0.001). CONCLUSIONS: Compared to donors aged 18-39, age 40 and above is associated with worse adjusted recipient survival in heart transplantation. This survival difference becomes more pronounced as age increases to above 55. However, the survival rate among status IA patients who receive hearts from advanced age donors (≥55) is significantly better compared to similar status IA patients who are managed without transplantation.


Assuntos
Transplante de Coração/mortalidade , Sistema de Registros , Doadores de Tecidos/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/organização & administração , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Idoso , Bases de Dados Factuais , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Modelos de Riscos Proporcionais , Risco , Taxa de Sobrevida , Adulto Jovem
11.
J Neurosci ; 31(13): 5067-77, 2011 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-21451044

RESUMO

The heat and capsaicin receptor, TRPV1, is required for the detection of painful heat by primary afferent pain fibers (nociceptors), but the extent to which functional TRPV1 channels are expressed in the CNS is debated. Because previous evidence is based primarily on indirect physiological responses to capsaicin, here we genetically modified the Trpv1 locus to reveal, with excellent sensitivity and specificity, the distribution of TRPV1 in all neuronal and non-neuronal tissues. In contrast to reports of widespread and robust expression in the CNS, we find that neuronal TRPV1 is primarily restricted to nociceptors in primary sensory ganglia, with minimal expression in a few discrete brain regions, most notably in a contiguous band of cells within and adjacent to the caudal hypothalamus. We confirm hypothalamic expression in the mouse using several complementary approaches, including in situ hybridization, calcium imaging, and electrophysiological recordings. Additional in situ hybridization experiments in rat, monkey, and human brain demonstrate that the restricted expression of TRPV1 in the CNS is conserved across species. Outside of the CNS, we find TRPV1 expression in a subset of arteriolar smooth muscle cells within thermoregulatory tissues. Here, capsaicin increases calcium uptake and induces vasoconstriction, an effect that likely counteracts the vasodilation produced by activation of neuronal TRPV1.


Assuntos
Arteríolas/metabolismo , Química Encefálica/genética , Regulação da Expressão Gênica , Genes Reporter , Miócitos de Músculo Liso/metabolismo , Canais de Cátion TRPV/biossíntese , Animais , Arteríolas/química , Humanos , Hipotálamo/química , Hipotálamo/metabolismo , Macaca fascicularis , Masculino , Camundongos , Camundongos Transgênicos , Miócitos de Músculo Liso/química , Ratos , Ratos Sprague-Dawley , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/fisiologia , Vasoconstrição/genética , Vasodilatação/genética
12.
Nat Neurosci ; 11(7): 772-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18568022

RESUMO

In traditional folk medicine, Xanthoxylum plants are referred to as 'toothache trees' because their anesthetic or counter-irritant properties render them useful in the treatment of pain. Psychophysical studies have identified hydroxy-alpha-sanshool as the compound most responsible for the unique tingling and buzzing sensations produced by Szechuan peppercorns or other Xanthoxylum preparations. Although it is generally agreed that sanshool elicits its effects by activating somatosensory neurons, the underlying cellular and molecular mechanisms remain a matter of debate. Here we show that hydroxy-alpha-sanshool excites two types of sensory neurons, including small-diameter unmyelinated cells that respond to capsaicin (but not mustard oil) as well as large-diameter myelinated neurons that express the neurotrophin receptor TrkC. We found that hydroxy-alpha-sanshool excites neurons through a unique mechanism involving inhibition of pH- and anesthetic-sensitive two-pore potassium channels (KCNK3, KCNK9 and KCNK18), providing a framework for understanding the unique and complex psychophysical sensations associated with the Szechuan pepper experience.


Assuntos
Amidas/farmacologia , Neurônios Aferentes/efeitos dos fármacos , Piper nigrum/química , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio de Domínios Poros em Tandem/fisiologia , Análise de Variância , Animais , Comportamento Animal/efeitos dos fármacos , Capsaicina/farmacologia , Células Cultivadas , Estimulação Elétrica/métodos , Gânglios Sensitivos/citologia , Regulação da Expressão Gênica/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Knockout , Proteínas de Neurofilamentos/metabolismo , Técnicas de Patch-Clamp , Canais de Potássio de Domínios Poros em Tandem/efeitos dos fármacos , Cloreto de Potássio/farmacologia , Receptor trkC/metabolismo , Canal de Cátion TRPA1 , Canais de Cátion TRPV/deficiência , Canais de Potencial de Receptor Transitório/deficiência
13.
Rev Med Suisse ; 7(314): 2084, 2086-8, 2011 Oct 26.
Artigo em Francês | MEDLINE | ID: mdl-22141307

RESUMO

Genital prolapse is frequent and can be found in about 50% of parous women. Its etiology is complex and multifactorial. Predisposing factors include: genetics (connective tissue disorders, family history); general state (age, parity, weight, smoking, obstructive pulmonary disease); trauma (carrying heavy loads, intense physical exercise); or iatrogenic (post hysterectomy). Treatment can be conservative or surgical and depends mainly on the severity of symptoms. Developments in surgical techniques and synthetic material in the last 20 years enabled us to use minimally invasive procedures with improved post operative course and decreased recurrence rates.


Assuntos
Laparoscopia , Telas Cirúrgicas , Prolapso Uterino/cirurgia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias
14.
Case Rep Cardiol ; 2021: 8878358, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33510915

RESUMO

Giant coronary aneurysms are late sequelae of Kawasaki disease (KD). We describe a 53-year-old patient who presented with acute myocardial infarction and proximal aneurysms of all three coronary arteries. Coronary angiography demonstrated the aneurysms, but CT angiography allowed accurate assessment of the real dimensions of the aneurysms and making the decision on the preferred method of revascularization. The patient underwent coronary bypass surgery and is asymptomatic at follow-up.

15.
Clin Exp Rheumatol ; 27(5 Suppl 56): S33-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20074437

RESUMO

BACKGROUND: Substance P receptor modulates stress, depression, anxiety and pain. Substance P is increased in CSF of fibromyalgia (FMS) patients. We examined the frequency of the substance P receptor (TACR1) 1354 G>C polymorphism in FMS.The dopamine transporter (DAT) SLC6A3 3' variable number tandem repeat (VNTR) polymorphism is associated with post traumatic stress disorder (PTSD), a condition with clinical and epidemiological overlap with FMS. We have evaluated the allele frequency of this polymorphism in FMS.Alpha1-antitrypsin (AAT) deficiency is an autosomal recessive metabolic disease. The PI ZZ phenotype, encoded by the E342K mutation, is associated with emphysema and liver disease, and has been linked with FMS. We have examined the frequency of this mutation in FMS. METHODS: Eighty-seven Jewish FMS patients participated; 45 of Ashkenazi origin, 32 of non-Ashkenazi origin and 10 of unknown or mixed Jewish origin. Controls consisted of 200 healthy Jewish individuals. Genotyping of the 1354G >C allele in the 3' UTR of TACR1 gene was performed by DdeI restriction analysis, genotyping the SCL6A3 DAT 3' VNTR polymorphism was performed by PCR combined with GeneScan analysis, and the AAT E342K mutation was identified by TaqI restriction analysis. RESULTS: No significant association was found between FMS and the three genetic markers studied here. CONCLUSIONS: The current candidate-gene approach study failed to identify significant associations between FMS and three genetic markers with hypothesis-driven clinical relevance. We suggest that a genome-wide association study would be a more fruitful approach for further investigation of the genetic basis of FMS.


Assuntos
Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Fibromialgia/genética , Receptores da Neurocinina-1/genética , alfa 1-Antitripsina/genética , Adulto , Alelos , Distribuição de Qui-Quadrado , Feminino , Frequência do Gene , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Israel , Judeus/genética , Masculino , Pessoa de Meia-Idade , Mutação , Razão de Chances , Polimorfismo de Nucleotídeo Único/genética
16.
Gynecol Obstet Fertil Senol ; 46(4): 414-418, 2018 Apr.
Artigo em Francês | MEDLINE | ID: mdl-29627410

RESUMO

INTRODUCTION: Intrauterine device (IUD) is a reliable contraceptive method that is long term reversible, and well tolerated. Numerous studies prove its efficiency and report rare complications that are attributed to it. However, its use is limited due to fear that it can cause a pelvic inflammatory disease (PID). This is based on historical data on infections related to the "Dalkon Shield", which was removed from the market in 1974. METHOD: The analyzed articles were extracted from PUBMED database between 2000 and 2016. In total, 22 studies were retained. A meta-analysis was not possible due to the methodological diversity among the selected articles contributing to this narrative review of the literature. RESULTS: After analysis, the following factors influence the risk of PID linked to IUDs: an advanced age and sexually transmitted infections. CONCLUSION: The risk of PID linked to IUDs is lower than 1%. This is explained by new models of IUD, better screening tests, more frequent follow-up of the patients and the improvement of care PID patients. In the light of our results, the threat of pelvic inflammatory disease should not hinder the use of IUDs.


Assuntos
Dispositivos Intrauterinos/efeitos adversos , Doença Inflamatória Pélvica/epidemiologia , Adulto , Fatores Etários , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Infecções Sexualmente Transmissíveis/complicações
17.
Science ; 361(6405): 880-887, 2018 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-30166485

RESUMO

Super-resolution microscopy has overcome a long-held resolution barrier-the diffraction limit-in light microscopy and enabled visualization of previously invisible molecular details in biological systems. Since their conception, super-resolution imaging methods have continually evolved and can now be used to image cellular structures in three dimensions, multiple colors, and living systems with nanometer-scale resolution. These methods have been applied to answer questions involving the organization, interaction, stoichiometry, and dynamics of individual molecular building blocks and their integration into functional machineries in cells and tissues. In this Review, we provide an overview of super-resolution methods, their state-of-the-art capabilities, and their constantly expanding applications to biology, with a focus on the latter. We will also describe the current technical challenges and future advances anticipated in super-resolution imaging.


Assuntos
Células/ultraestrutura , Imageamento Tridimensional/métodos , Microscopia de Fluorescência/métodos , Imagem Molecular/métodos , Animais , Humanos , Neurônios/ultraestrutura , Sinapses/ultraestrutura
19.
Rev Med Suisse ; 2(53): 456-9, 2006 Feb 15.
Artigo em Francês | MEDLINE | ID: mdl-16533003

RESUMO

The overall increase in relative survival rates of adult and childhood cancer patients is related to improved chemotherapy and radiotherapy treatment protocols. However, this success is tempered by gonadotoxic effects and uterine damage. The reduced fertility and possible premature menopause can have a profound impact on patients self-esteem and quality of life. Consequently, preservation of fertility or treatments to protect the ovarian function, become a more relevant issue. Advances in assisted reproduction techniques have focused on the following: embryo cryopreservation which is restricted by time and constrains such as, sexual maturity and the presence of a stable partner. Cryopreservation of immature ovarian tissue, the most promising option, with restoration of natural fertility following auto-transplantation or maturation of oocytes in vitro in combination with assisted reproduction.


Assuntos
Infertilidade Feminina/etiologia , Neoplasias/terapia , Criopreservação , Feminino , Humanos , Ovário
20.
Steroids ; 95: 104-10, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25595451

RESUMO

INTRODUCTION: Estetrol (E4), a naturally occurring estrogen produced exclusively by human fetal liver, is currently being evaluated for potential use in contraception and menopausal care in humans. The present study was designed to profile E4 effects on the central nervous system, to assess the in vivo effects of E4 administration on Beta-Endorphin (ß-END) release in specific brain structures and to evaluate whether E4 has synergic or antagonistic effects on estradiol-mediated ß-END synthesis. EXPERIMENTAL: Intact female adult rats received different doses of E4 and ovariectomized (OVX) rats received different doses of E4 or E2V or combinations of both drugs. The concentrations of ß-END were assessed in the frontal and parietal cortex, hippocampus, hypothalamus, neurointermediate lobe, anterior pituitary and plasma. RESULTS: E4 at the dose of 1mg/kg/day did not alter ß-END content in most brain areas, as well as, plasma levels of intact animals E4 administered at a dose of 5mg/kg/day decreased ß-END content in the hippocampus, hypothalamus, and in the neurointermediate lobe, as well as, plasma levels, compared to intact animals receiving vehicle. E4 increased ß-END values in the frontal cortex, but not in the plasma, following the administration of 1mg/kg/day in OVX rats, whereas treatment with 5mg/kg/day in OVX rats induced a significant increase in ß-END levels in most brain areas and in the plasma. However, in the presence of estradiol, E4 showed an estrogen-antagonistic effect in selected brain structures at the dose of 5mg/kg/day and in plasma levels of ß-END at the dose of 1mg/kg/day and 5mg/kg/day. CONCLUSION: In OVX rats, E4 increases CNS and peripheral levels of ß-END, behaving as a weak estrogen-agonist. The antagonistic effect observed after combined estradiol and E4 administration further profiles E4 as a natural SERM.


Assuntos
Estetrol/farmacologia , beta-Endorfina/metabolismo , Animais , Relação Dose-Resposta a Droga , Antagonismo de Drogas , Sinergismo Farmacológico , Estradiol/análogos & derivados , Estradiol/farmacologia , Feminino , Ovariectomia , Ratos , Ratos Wistar
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