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Pesquisa : G08.686.195 [Categoria DeCS]
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[PMID]:29377248
[Au] Autor:Kozlowski CP; Clawitter HL; Thier T; Fischer MT; Asa CS
[Ad] Endereço:Reproductive and Behavioral Sciences, Saint Louis Zoo, St. Louis, Missouri.
[Ti] Título:Characterization of estrous cycles and pregnancy in Somali wild asses (Equus africanus somaliensis) through fecal hormone analyses.
[So] Source:Zoo Biol;37(1):35-39, 2018 Jan.
[Is] ISSN:1098-2361
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Although reproduction in the domestic horse has been well described, less is known about reproduction in wild equids. This study describes endocrine patterns associated with estrous cycles and pregnancy for Somali wild asses (Equus africanus somaliensis), an endangered African equid. Fecal samples were collected three times per week for more than 2 years from five female Somali wild asses at the Saint Louis Zoo; progestagen and estrogen metabolites were quantified using commercially available immunoassays. Progestagen analysis indicated that cycle lengths were 27.2 ± 1.2 days and females cycled throughout the year. Progestagen levels during early pregnancy were low and not sustained above baseline until approximately 40 weeks prior to partition. Concentrations increased markedly around 16 weeks prior to delivery and peaked 2-3 weeks before birth. Fecal estrogen levels also increased significantly starting 40-45 weeks before parturition and reached their maximal value approximately 20 weeks prior to birth. Neither foal heat nor lactational suppression of estrus was observed, and females cycled within 45 days after delivery. These data are the first to describe the reproductive physiology of Somali wild asses. As the species faces increasing threats in the wild, this information may support conservation efforts by assisting with ex situ breeding programs.
[Mh] Termos MeSH primário: Equidae/fisiologia
Estrogênios/metabolismo
Ciclo Estral/fisiologia
Fezes/química
Prenhez
Progestinas/metabolismo
[Mh] Termos MeSH secundário: Criação de Animais Domésticos
Animais
Animais de Zoológico
Estrogênios/química
Feminino
Gravidez
Progestinas/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Estrogens); 0 (Progestins)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180130
[St] Status:MEDLINE
[do] DOI:10.1002/zoo.21397


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[PMID]:28542730
[Au] Autor:Perez PA; Petiti JP; Picech F; Guido CB; dV Sosa L; Grondona E; Mukdsi JH; De Paul AL; Torres AI; Gutierrez S
[Ad] Endereço:Centro de Microscopia Electrónica, Instituto de Investigaciones en Ciencias de la Salud (INICSA-CONICET), Facultad de Ciencias Medicas, Universidad Nacional de Cordoba, Cordoba, Argentina.
[Ti] Título:Estrogen receptor ß regulates the tumoral suppressor PTEN to modulate pituitary cell growth.
[So] Source:J Cell Physiol;233(2):1402-1413, 2018 Feb.
[Is] ISSN:1097-4652
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In this study, we focused on ERß regulation in the adenohypophysis under different estrogenic milieu, by analyzing whether ER modulates the phosphatase and tensin homolog deleted on chromosome 10 (PTEN) expression and its subcellular localization on anterior pituitary glands from Wistar rats and GH3 lactosomatotroph cells that over-expressed ERß. ERß was regulated in a cyclic manner, and underwent dynamic changes throughout the estrous cycle, with decreased ERß+ cells in estrus and under E2 treatment, but increased in ovariectomized rats. In addition, the ERα/ß ratio increased in estrus and under E2 stimulation, but decreased in ovariectomized rats. Double immunofluorescence revealed that lactotroph and somatotroph ERß+ were significantly decreased in estrus. Also, variations in the PTEN expression was observed, which was diminished with high E2 conditions but augmented with low E2 milieu. The subcellular localization of this phosphatase was cell cycle-dependent, with remarkable changes in the immunostaining pattern: nuclear in arrested pituitary cells but cytoplasmic in stimulated cells, and responding differently to ER agonists, with only DPN being able to increase PTEN expression and retaining it in the nucleus. Finally, ERß over-expression increased PTEN with a noticeable subcellular redistribution, and with a significant nuclear signal increase in correlation with an increase of cells in G0/G1 phase. These results showed that E2 is able to inhibit ERß expression and suggests that the tumoral suppressor PTEN might be one of the signaling proteins by which E2, through ERß, acts to modulate pituitary cell proliferation, thereby adapting endocrine populations in relation with hormonal necessities.
[Mh] Termos MeSH primário: Proliferação Celular
Receptor beta de Estrogênio/metabolismo
Ciclo Estral/metabolismo
Lactotrofos/enzimologia
PTEN Fosfo-Hidrolase/metabolismo
Somatotrofos/enzimologia
[Mh] Termos MeSH secundário: Animais
Células Cultivadas
Estradiol/metabolismo
Estradiol/farmacologia
Receptor beta de Estrogênio/agonistas
Receptor beta de Estrogênio/genética
Terapia de Reposição de Estrogênios
Feminino
Fase G1
Lactotrofos/efeitos dos fármacos
Masculino
Nitrilos/farmacologia
Ovariectomia
Ratos Wistar
Transdução de Sinais
Somatotrofos/efeitos dos fármacos
Transfecção
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (2,3-bis(4-hydroxyphenyl)-propionitrile); 0 (Estrogen Receptor beta); 0 (Nitriles); 4TI98Z838E (Estradiol); EC 3.1.3.67 (PTEN Phosphohydrolase); EC 3.1.3.67 (Pten protein, rat)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171128
[Lr] Data última revisão:
171128
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170526
[St] Status:MEDLINE
[do] DOI:10.1002/jcp.26025


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[PMID]:28842205
[Au] Autor:Jean PA; Sloter ED; Plotzke KP
[Ad] Endereço:Dow Corning Corporation, Midland, MI, 48686, United States. Electronic address: pajean4@gmail.com.
[Ti] Título:Effects of chronic exposure to octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane in the aging female Fischer 344 rat.
[So] Source:Toxicol Lett;279 Suppl 1:54-74, 2017 Oct 20.
[Is] ISSN:1879-3169
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5) are used as intermediates or monomers in the synthesis of silicon-based polymers for industrial or consumer applications. D4 and D5 may remain as residual monomer in these polymers at less than 1000ppm and may therefore be present as a minor impurity in consumer products. For D5, in addition to the manufacture of polymers, its uses include intentional addition to consumer products, personal care products and some dry- cleaning solvents. Two-year rodent chronic bioassays were conducted with both substances and borderline increases in the incidence of uterine tumors were observed, specifically, benign uterine adenoma with D4 and adenocarcinoma with D5. The effects profile and induction of uterine tumors share some similarity with that seen with chronic exposure to dopamine agonists. The current study investigated the potential for D4 and D5 to elicit dopamine agonist-like effects on estrous cyclicity. Separate groups of reproductively senescent female Fischer 344 rats (F344) were exposed via vapor inhalation to D4 (700ppm, 9.3mg/L) or D5 (160ppm, 2.1mg/L) or to a diet containing 0.0045, 0.045, or 4.5ppm pergolide mesylate (PM), a potent dopamine agonist used here as a reference substance, from 11 through 24 months of age. The primary focus was to characterize the effects of D4 and D5 exposure on estrous cyclicity relative to that observed with PM. As a monitoring effort, circulating endogenous estradiol, progesterone, prolactin and corticosterone levels were evaluated monthly. A blood sample from each rat was obtained via tail vein in the afternoon after the daily inhalation exposure period once every 4 weeks. Histomorphologic examination of the major organs including the reproductive tract was conducted on all animals at study termination. This study has shown that chronic exposure to D4 and D5 can affect cyclicity in the reproductively senescent F344 rat. For each substance the effect on cyclicity involved reduction in the incidence of pseudopregnancy with a shift toward cycles more typical of younger animals. D4 and D5 induced an increase in estrous cycle repetition whereas D4 also increased the incidence of extended estrus. These shifts resulted in animals entering proestrus/estrus significantly more times over the duration of the study than seen in the control group. Similar effects were observed with the reference substance, PM. However, distinct differences in the timing and magnitude of the effects on the estrous cycle and impact on prolactin, progesterone, estradiol, and corticosterone suggest that D4 and D5 are not classical dopamine agonists even though a similar increased incidence of proestrus/estrus was also observed with PM. These results may prove important with respect to understanding D4- and D5-induced uterine tumor response in the F344 rat, given the relationship between increased incidence of uterine endometrium stimulation by endogenous estrogen as a consequence of extended or more frequent proestrus/estrus, uterine tumor risk, and questions of relevance to humans. Recent publications have summarized the existing data on D4 and D5, with emphasis on exploring the biological relevance of the uterine tumors (Klaunig et al., 2016a,b; Franzen et al., 2017; Dekant and Klaunig, 2016; Dekant et al., 2017). The authors concluded that although the mode of action has not yet been fully established, the data, including the findings from this study, indicate that the D4- and D5-induced uterine tumors observed in the rodent chronic bioassays have no relevance for human risk characterization based not only on the distinct species differences in regulation of the reproductive systems, but also the high exposure levels and duration required for expression in rats.
[Mh] Termos MeSH primário: Siloxanas/toxicidade
[Mh] Termos MeSH secundário: Envelhecimento
Ração Animal/análise
Animais
Dieta/veterinária
Esquema de Medicação
Ciclo Estral
Feminino
Exposição por Inalação
Pergolida/administração & dosagem
Ratos
Ratos Endogâmicos F344
Siloxanas/administração & dosagem
Siloxanas/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Siloxanes); 0THT5PCI0R (decamethylcyclopentasiloxane); 24MJ822NZ9 (Pergolide); CZ227117JE (octamethylcyclotetrasiloxane)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171006
[Lr] Data última revisão:
171006
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170827
[St] Status:MEDLINE


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[PMID]:28809605
[Au] Autor:Imaoka T; Nishimura M; Daino K; Hosoki A; Takabatake M; Kokubo T; Doi K; Showler K; Nishimura Y; Moriyama H; Morioka T; Shimada Y; Kakinuma S
[Ad] Endereço:a Department of Radiation Effects Research, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba 263-8555, Japan.
[Ti] Título:Age Modifies the Effect of 2-MeV Fast Neutrons on Rat Mammary Carcinogenesis.
[So] Source:Radiat Res;188(4):419-425, 2017 Oct.
[Is] ISSN:1938-5404
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The relative biological effectiveness (RBE) of neutrons depends on their physical nature (e.g., energy) and the biological context (e.g., end points, materials). From the perspective of radiological protection, age is an important biological context that influences radiation-related cancer risk, but very few studies have addressed its potential impact on neutron effects. We therefore investigated the influence of age on the effect of accelerator-generated fast neutrons (mean energy, ∼2 MeV) in an animal model of breast carcinogenesis. Female Sprague-Dawley rats at 1, 3 and 7 weeks of age were irradiated with fast neutrons at absorbed doses of 0.0485-0.97 Gy. All animals were kept under specific pathogen-free conditions and screened weekly for mammary tumors by palpation until they were 90 weeks old. Tumors were diagnosed based on histology. Mathematical modeling was used to analyze mammary cancer incidence, collectively using data from this study and a previously reported experiment on Cs gamma rays. The results indicate that neutron irradiation elevated the risk of palpable mammary carcinoma with a linear dose response, the slope of which depended on age at time of irradiation. The RBE of neutron radiation was 7.5 ± 3.4, 9.3 ± 3.5 and 26.1 ± 8.9 (mean ± SE) for animals exposed at 1, 3 and 7 weeks of age, respectively. Our results indicate that age of the animal is an important factor influencing the effect of fast neutrons on breast cancer risk.
[Mh] Termos MeSH primário: Envelhecimento
Nêutrons Rápidos/efeitos adversos
Neoplasias Mamárias Experimentais/etiologia
Neoplasias Mamárias Experimentais/fisiopatologia
[Mh] Termos MeSH secundário: Envelhecimento/efeitos da radiação
Animais
Ciclo Estral/efeitos da radiação
Feminino
Neoplasias Induzidas por Radiação/etiologia
Neoplasias Induzidas por Radiação/fisiopatologia
Ratos
Ratos Sprague-Dawley
Eficiência Biológica Relativa
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171017
[Lr] Data última revisão:
171017
[Sb] Subgrupo de revista:IM; S
[Da] Data de entrada para processamento:170816
[St] Status:MEDLINE
[do] DOI:10.1667/RR14829.1


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[PMID]:28698031
[Au] Autor:Free KE; Greene AM; Bondi CO; Lajud N; de la Tremblaye PB; Kline AE
[Ad] Endereço:Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA 15213, United States; Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA 15213, United States.
[Ti] Título:Comparable impediment of cognitive function in female and male rats subsequent to daily administration of haloperidol after traumatic brain injury.
[So] Source:Exp Neurol;296:62-68, 2017 Oct.
[Is] ISSN:1090-2430
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Antipsychotic drugs, such as haloperidol (HAL), are prescribed in the clinic to manage traumatic brain injury (TBI)-induced agitation. While preclinical studies have consistently shown that once-daily administration of HAL hinders functional recovery after TBI in male rats, its effects in females are unknown. Hence, the objective of this study was to directly compare neurobehavioral and histological outcomes in both sexes to determine whether the reported deleterious effects of HAL extend to females. Anesthetized adult female and male rats received either a controlled cortical impact (CCI) or sham injury and then were randomly assigned to a dosing regimen of HAL (0.5mg/kg, i.p.) or vehicle (VEH; 1mL/kg, i.p.) that was initiated 24h after injury and continued once daily for 19 consecutive days. Motor function was tested using established beam-balance/walk protocols on post-operative days 1-5 and acquisition of spatial learning was assessed with a well-validated Morris water maze task on days 14-19. Cortical lesion volume was quantified at 21days. No statistical differences were revealed between the HAL and VEH-treated sham groups and thus they were pooled for each sex. HAL only impaired motor recovery in males (p<0.05), but significantly diminished spatial learning in both sexes (p<0.05). Females, regardless of treatment, exhibited smaller cortical lesions vs VEH-treated males (p<0.05). Taken together, the data show that daily HAL does not prohibit motor recovery in females, but does negatively impact cognition. These task-dependent differential effects of HAL in female vs male rats may have clinical significance as they can direct therapy.
[Mh] Termos MeSH primário: Antipsicóticos/efeitos adversos
Lesões Encefálicas Traumáticas/tratamento farmacológico
Lesões Encefálicas Traumáticas/fisiopatologia
Cognição/efeitos dos fármacos
Haloperidol/efeitos adversos
Caracteres Sexuais
[Mh] Termos MeSH secundário: Análise de Variância
Animais
Modelos Animais de Doenças
Ciclo Estral/efeitos dos fármacos
Feminino
Masculino
Atividade Motora/efeitos dos fármacos
Exame Neurológico
Desempenho Psicomotor/efeitos dos fármacos
Ratos
Ratos Sprague-Dawley
Retenção (Psicologia)/efeitos dos fármacos
Aprendizagem Espacial/efeitos dos fármacos
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antipsychotic Agents); J6292F8L3D (Haloperidol)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170822
[Lr] Data última revisão:
170822
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170713
[St] Status:MEDLINE


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[PMID]:28678802
[Au] Autor:Zhang L; Liu X; Liu J; Zhou Z; Song Y; Cao B; An X
[Ad] Endereço:College of Animal Science and Technology, Northwest Agriculture and Forestry University, Yangling, Shaanxi, China.
[Ti] Título:miR-182 aids in receptive endometrium development in dairy goats by down-regulating PTN expression.
[So] Source:PLoS One;12(7):e0179783, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Increasing evidence has shown that miRNAs play important roles in endometrium development during the menstrual cycle in humans and many other animals. Our previous data indicated that miR-182 levels increase 15.55-fold and pleiotrophin (PTN) levels decrease 20.97-fold in the receptive endometrium (RE, D15) compared with the pre-receptive endometrium (PE, D5) in dairy goats. The present study shows that miR-182 is widely expressed in different tissues of dairy goats and that its expression levels are regulated by E2 and P4 in endometrial epithelium cells (EECs). We confirmed that PTN is a target of miR-182 and that miR-182 regulates the protein levels of AKT, Bcl-2, FAS, MAPK, Caspase-3 and SP1 in EECs. Furthermore, miR-182 up-regulates or maintains the expression levels of osteopontin (OPN), cyclooxygenase-2 (COX-2) and prolactin receptor (PRLR) in EECs, suggesting that miR-182 is an important regulatory factor in the construction of endometrial receptivity in dairy goats. In conclusion, miR-182 participates in the development of endometrial receptivity by down-regulating PTN and affecting the expression of select apoptosis-related genes and increasing or maintaining the expression levels of OPN, COX-2 and PRLR in the EECs of dairy goats.
[Mh] Termos MeSH primário: Proteínas de Transporte/genética
Citocinas/genética
Endométrio/metabolismo
Cabras/metabolismo
MicroRNAs/fisiologia
[Mh] Termos MeSH secundário: Regiões 3' não Traduzidas
Animais
Apoptose
Sequência de Bases
Sítios de Ligação
Proteínas de Transporte/metabolismo
Proliferação Celular
Células Cultivadas
Citocinas/metabolismo
Regulação para Baixo
Endométrio/citologia
Células Endoteliais/fisiologia
Estradiol/fisiologia
Ciclo Estral
Feminino
Expressão Gênica
Cabras/genética
Progesterona/fisiologia
Proteínas Proto-Oncogênicas c-akt/metabolismo
Interferência de RNA
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (3' Untranslated Regions); 0 (Carrier Proteins); 0 (Cytokines); 0 (MicroRNAs); 134034-50-7 (pleiotrophin); 4G7DS2Q64Y (Progesterone); 4TI98Z838E (Estradiol); EC 2.7.11.1 (Proto-Oncogene Proteins c-akt)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170922
[Lr] Data última revisão:
170922
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170706
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0179783


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[PMID]:28599864
[Au] Autor:Abdel-Latif RT; Zaitone SA; Abdel-Mottaleb Y; El-Maraghy NN
[Ad] Endereço:Department of Pharmacology, Toxicology & Biochemistry, Faculty of Pharmaceutical Sciences and Pharmaceutical Industries, Future University in Egypt, Cairo, Egypt.
[Ti] Título:The anorectic agent, lorcaserin, disturbs estrous cyclicity and produces endometrial hyperplasia without affecting ovarian population in female rats.
[So] Source:Life Sci;183:69-77, 2017 Aug 15.
[Is] ISSN:1879-0631
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:AIMS: The present study aims to investigate the effect of the new anorectic agent, lorcaserin, on estrous cyclicity, reproductive hormones and folliculogenesis in female mature rats. MATERIALS AND METHODS: Rats were divided into four groups; Group i: control group. Group ii-iv: rats treated with lorcaserin (5, 10 or 30mg/kg/day, p.o.), respectively. The treatment continued for 28days. KEY FINDINGS: Lorcaserin (5 or 10mg/kg) caused estrous cycle disturbance in 40% of treated rats while the high dose (30mg/kg) produced disturbances in 100% of the treated rats. Lorcaserin (5-30mg/kg) altered some of female hormones where it enhanced estradiol but reduced luteinizing hormone. Minimal edema with congested vessels was observed in the medulla of ovarian sections. Further, epithelial and uterine sections showed hyperplasia. SIGNIFICANCE: Taken together, the present results demonstrated that lorcaserin affected some reproductive hormones, disturbed estrous cyclicity and induced histopathological changes in the ovaries and uteri without affecting the ovarian populations. Therefore, lorcaserin should be used with caution in women of child bearing potential until adequate clinical safety data are available.
[Mh] Termos MeSH primário: Depressores do Apetite/farmacologia
Benzazepinas/farmacologia
Hiperplasia Endometrial/induzido quimicamente
Ciclo Estral/efeitos dos fármacos
Ovário/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Depressores do Apetite/administração & dosagem
Benzazepinas/administração & dosagem
Relação Dose-Resposta a Droga
Estradiol/metabolismo
Feminino
Hormônio Luteinizante/metabolismo
Folículo Ovariano/efeitos dos fármacos
Ovário/patologia
Ratos
Ratos Wistar
Útero/efeitos dos fármacos
Útero/patologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Appetite Depressants); 0 (Benzazepines); 4TI98Z838E (Estradiol); 637E494O0Z (lorcaserin); 9002-67-9 (Luteinizing Hormone)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170808
[Lr] Data última revisão:
170808
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170611
[St] Status:MEDLINE


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[PMID]:28592693
[Au] Autor:Dougherty BJ; Kopp ES; Watters JJ
[Ad] Endereço:Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53706.
[Ti] Título:Nongenomic Actions of 17-ß Estradiol Restore Respiratory Neuroplasticity in Young Ovariectomized Female Rats.
[So] Source:J Neurosci;37(28):6648-6660, 2017 Jul 12.
[Is] ISSN:1529-2401
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Gonadal steroids modulate CNS plasticity, including phrenic long-term facilitation (pLTF), a form of spinal respiratory neuroplasticity resulting in increased phrenic nerve motor output following exposure to acute intermittent hypoxia (aIH; three 5 min episodes, 10.5% O ). Despite the importance of respiratory system neuroplasticity, and its dependence on estrogen in males, little is known about pLTF expression or mechanisms of estrogen signaling in females. Here, we tested the hypotheses that (1) pLTF expression in young, gonadally intact female rats would be expressed during estrous cycle stages in which 17ß-estradiol (E2) is naturally high (e.g., proestrus vs estrus), (2) pLTF would be absent in ovariectomized (OVX) rats and in physiological conditions in which serum progesterone, but not E2, is elevated (e.g., lactating rats, 3-10 d postpartum), and (3) acute E2 administration would be sufficient to restore pLTF in OVX rats. Recordings of phrenic nerve activity in female Sprague Dawley rats (3-4 months) revealed a direct correlation between serum E2 levels and pLTF expression in cycling female rats. pLTF was abolished with OVX, but was re-established by acute E2 replacement (3 h, intraperitoneal). To identify underlying E2 signaling mechanisms, we intrathecally applied BSA-conjugated E2 over the spinal phrenic motor nucleus and found that pLTF expression was restored within 15 min, suggesting nongenomic E2 effects at membrane estrogen receptors. These data are the first to investigate the role of ovarian E2 in young cycling females, and to identify a role for nongenomic estrogen signaling in any form of respiratory system neuroplasticity. Exposure to acute intermittent hypoxia induces phrenic long-term facilitation (pLTF), a form of spinal respiratory motor plasticity that improves breathing in models of spinal cord injury. Although pathways leading to pLTF are well studied in males and estradiol (E2) is known to be required, it has seldom been investigated in females, and underlying mechanisms of E2 signaling are unknown in either sex. We found that while ovariectomy abolished pLTF, it could be restored by acute systemic E2, or by intraspinal application of the membrane-impermeable E2 (BSA-conjugated E2; 15 min). The ability of nongenomic estrogen signaling within the cervical spinal cord to recover respiratory neuroplasticity in disorders of respiratory insufficiency suggests that membrane estrogen receptors may represent novel therapeutic targets to restore breathing in both sexes.
[Mh] Termos MeSH primário: Estradiol/farmacologia
Ciclo Estral/fisiologia
Potenciação de Longa Duração/fisiologia
Plasticidade Neuronal/fisiologia
Nervo Frênico/fisiologia
Mecânica Respiratória/fisiologia
[Mh] Termos MeSH secundário: Animais
Estrogênios/farmacologia
Ciclo Estral/efeitos dos fármacos
Feminino
Potenciação de Longa Duração/efeitos dos fármacos
Ovariectomia
Nervo Frênico/efeitos dos fármacos
Ratos
Ratos Sprague-Dawley
Mecânica Respiratória/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Estrogens); 4TI98Z838E (Estradiol)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170818
[Lr] Data última revisão:
170818
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170609
[St] Status:MEDLINE
[do] DOI:10.1523/JNEUROSCI.0433-17.2017


  9 / 3858 MEDLINE  
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[PMID]:28582470
[Au] Autor:Bi RY; Meng Z; Zhang P; Wang XD; Ding Y; Gan YH
[Ad] Endereço:The Third Dental Center, Peking University School and Hospital of Stomatology, Haidian District, Beijing, China.
[Ti] Título:Estradiol upregulates voltage-gated sodium channel 1.7 in trigeminal ganglion contributing to hyperalgesia of inflamed TMJ.
[So] Source:PLoS One;12(6):e0178589, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Temporomandibular disorders (TMDs) have the highest prevalence in women of reproductive age. The role of estrogen in TMDs and especially in TMDs related pain is not fully elucidated. Voltage-gated sodium channel 1.7 (Nav1.7) plays a prominent role in pain perception and Nav1.7 in trigeminal ganglion (TG) is involved in the hyperalgesia of inflamed Temporomandibular joint (TMJ). Whether estrogen could upregulate trigeminal ganglionic Nav1.7 expression to enhance hyperalgesia of inflamed TMJ remains to be explored. METHODS: Estrous cycle and plasma levels of 17ß-estradiol in female rats were evaluated with vaginal smear and enzyme linked immunosorbent assay, respectively. Female rats were ovariectomized and treated with 17ß-estradiol at 0 µg, 20 µg and 80 µg, respectively, for 10 days. TMJ inflammation was induced using complete Freund's adjuvant. Head withdrawal thresholds and food intake were measured to evaluate the TMJ nociceptive responses. The expression of Nav1.7 in TG was examined using real-time PCR and western blot. The activity of Nav1.7 promoter was examined using luciferase reporter assay. The locations of estrogen receptors (ERα and ERß), the G protein coupled estrogen receptor (GPR30), and Nav1.7 in TG were examined using immunohistofluorescence. RESULTS: Upregulation of Nav1.7 in TG and decrease in head withdrawal threshold were observed with the highest plasma 17ß-estradiol in the proestrus of female rats. Ovariectomized rats treated with 80 µg 17ß-estradiol showed upregulation of Nav1.7 in TG and decrease in head withdrawal threshold as compared with that of the control or ovariectomized rats treated with 0 µg or 20 µg. Moreover, 17ß-estradiol dose-dependently potentiated TMJ inflammation-induced upregulation of Nav1.7 in TG and also enhanced TMJ inflammation-induced decrease of head withdrawal threshold in ovariectomized rats. In addition, the estrogen receptor antagonist, ICI 182,780, partially blocked the 17ß-estradiol effect on Nav1.7 expression and head withdrawal threshold in ovariectomized rats. ERα and ERß, but not GPR30, were mostly co-localized with Nav1.7 in neurons in TG. In the nerve growth factor-induced and ERα-transfected PC12 cells, 17ß-estradiol dose-dependently enhanced Nav1.7 promoter activity, whereas mutations of the estrogen response element at -1269/-1282 and -1214/-1227 in the promoter completely abolished its effect on the promoter activity. CONCLUSION: Estradiol could upregulate trigeminal ganglionic Nav1.7 expression to contribute to hyperalgesia of inflamed TMJ.
[Mh] Termos MeSH primário: Estradiol/farmacologia
Hiperalgesia/genética
Canal de Sódio Disparado por Voltagem NAV1.7/genética
Síndrome da Disfunção da Articulação Temporomandibular/genética
Articulação Temporomandibular/efeitos dos fármacos
Gânglio Trigeminal/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Estradiol/análogos & derivados
Estradiol/metabolismo
Antagonistas do Receptor de Estrogênio/farmacologia
Receptor alfa de Estrogênio/antagonistas & inibidores
Receptor alfa de Estrogênio/genética
Receptor alfa de Estrogênio/metabolismo
Receptor beta de Estrogênio/antagonistas & inibidores
Receptor beta de Estrogênio/genética
Receptor beta de Estrogênio/metabolismo
Ciclo Estral/fisiologia
Feminino
Adjuvante de Freund
Regulação da Expressão Gênica
Genes Reporter
Hiperalgesia/metabolismo
Hiperalgesia/patologia
Luciferases/genética
Luciferases/metabolismo
Canal de Sódio Disparado por Voltagem NAV1.7/metabolismo
Nociceptividade/efeitos dos fármacos
Ovariectomia
Regiões Promotoras Genéticas
Ratos
Ratos Sprague-Dawley
Receptores Acoplados a Proteínas-G/genética
Receptores Acoplados a Proteínas-G/metabolismo
Articulação Temporomandibular/inervação
Articulação Temporomandibular/metabolismo
Articulação Temporomandibular/patologia
Síndrome da Disfunção da Articulação Temporomandibular/induzido quimicamente
Síndrome da Disfunção da Articulação Temporomandibular/metabolismo
Síndrome da Disfunção da Articulação Temporomandibular/patologia
Gânglio Trigeminal/metabolismo
Gânglio Trigeminal/patologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Estrogen Receptor Antagonists); 0 (Estrogen Receptor alpha); 0 (Estrogen Receptor beta); 0 (GPR30 protein, rat); 0 (NAV1.7 Voltage-Gated Sodium Channel); 0 (Receptors, G-Protein-Coupled); 0 (Scn9a protein, rat); 22X328QOC4 (fulvestrant); 4TI98Z838E (Estradiol); 9007-81-2 (Freund's Adjuvant); EC 1.13.12.- (Luciferases)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170918
[Lr] Data última revisão:
170918
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170606
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0178589


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[PMID]:28569618
[Au] Autor:Louis GW; Hallinger DR; Braxton MJ; Kamel A; Stoker TE
[Ad] Endereço:a Endocrine Toxicology Branch, Toxicity Assessment Division , National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. EPA , Research Triangle Park , NC , USA.
[Ti] Título:Effects of chronic exposure to triclosan on reproductive and thyroid endpoints in the adult Wistar female rat.
[So] Source:J Toxicol Environ Health A;80(4):236-249, 2017.
[Is] ISSN:1528-7394
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Triclosan (TCS), an antibacterial, has been shown to be an endocrine disruptor in the rat. Previously, subchronic TCS treatment to female rats was found to advance puberty and potentiate the effect of ethinyl estradiol (EE) on uterine growth when EE and TCS were co-administered prior to weaning. In the pubertal study, a decrease in serum thyroxine (T ) concentrations with no significant change in serum thyroid-stimulating hormone (TSH) was also observed. The purpose of the present study was to further characterize the influence of TCS on the reproductive and thyroid axes of the female rat using a chronic exposure regimen. Female Wistar rats were exposed by oral gavage to vehicle control, EE (1 µg/kg), or TCS (2.35, 4.69, 9.375 or 37.5 mg/kg) for 8 months and estrous cyclicity monitored. Although a divergent pattern of reproductive senescence appeared to emerge from 5 to 11 months of age between controls and EE-treated females, no significant difference in cyclicity was noted between TCS-treated and control females. A higher % control females displayed persistent diestrus (PD) by the end of the study, whereas animals administered with positive control (EE) were predominately persistent estrus (PE). Thyroxine concentration was significantly decreased in TCS-administered 9.375 and 37.5 mg/kg groups, with no marked effects on TSH levels, thyroid tissue weight, or histology. Results demonstrate that a long-term exposure to TCS did not significantly alter estrous cyclicity or timing of reproductive senescence in females but suppressed T levels at a lower dose than previously observed.
[Mh] Termos MeSH primário: Envelhecimento/efeitos dos fármacos
Ciclo Estral/efeitos dos fármacos
Sistema Hipotálamo-Hipofisário/efeitos dos fármacos
Reprodução/efeitos dos fármacos
Glândula Tireoide/efeitos dos fármacos
Triclosan/toxicidade
[Mh] Termos MeSH secundário: Animais
Anti-Infecciosos Locais/toxicidade
Feminino
Ratos
Ratos Wistar
Testes de Toxicidade Crônica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Infective Agents, Local); 4NM5039Y5X (Triclosan)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170707
[Lr] Data última revisão:
170707
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170602
[St] Status:MEDLINE
[do] DOI:10.1080/15287394.2017.1287029



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