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1.
Neuroendocrinology ; : 1-12, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38697024

RESUMO

INTRODUCTION: In humans, prenatal androgen excess can lead to a broad spectrum of pathologies in adulthood, including polycystic ovary syndrome (PCOS). Women with PCOS present a variety of reproductive and metabolic disturbances and they also face increased risk to develop neuropsychiatric disorders such as depression and anxiety. Despite the high prevalence, the cause of depressive and anxiety symptoms is not fully elucidated. The use of androgenized ewe models can provide valuable insights into the pathogenesis of PCOS, as they closely mimic the reproductive, neuroendocrine, and metabolic characteristics observed in women with this condition. METHOD: We studied the impact of prenatal exposure to testosterone propionate on cognitive and behavioral performances of Ile-de-France ewes, using a plethora of behavioral tests for anxiety and cognitive performances. RESULTS: Our findings indicate that prenatal androgenized ewes exhibit markedly elevated levels of anxiety-like behavior compared to control animals, while showing no discernible differences in cognitive performance. CONCLUSION: These discoveries offer novel perspectives on how maternal androgen excess contributes to anxiogenic effects in PCOS preclinical models, underscoring the ewe's significance as a model for conducting mechanistic studies to unravel the physiological and molecular aspects of anxiety.

2.
Neuroendocrinology ; 113(2): 208-215, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35051936

RESUMO

Magnetic resonance imaging (MRI) brain analysis is used in rodents and for clinical investigation in humans, and it becomes also possible now for large animal models studies. Specific facilities are available with clinical scanners and benefit to neuroendocrine investigations in sheep. Sheep has a large gyrencephalic brain and its organization is very similar to primates and human, and among physiological regulations, oestrous cycle of the ewes is similar to women. Therefore, this animal is a good model for preclinical researches using MRI, as illustrated with steroids impact on the brain. New data were obtained concerning the effect of sexual steroids on neuronal networks involved in the control of reproduction and in the influence of sexual steroids on cognition. In addition to the importance of such data for understanding the role of these hormones on brain functions, they give new insights to consider the sheep as a powerful model for preclinical studies in the field of neuroendocrinology. These points are discussed in this short review.


Assuntos
Hormônios , Sistemas Neurossecretores , Animais , Ovinos , Feminino , Humanos , Sistemas Neurossecretores/fisiologia , Encéfalo/diagnóstico por imagem , Esteroides , Imageamento por Ressonância Magnética/métodos
3.
Neuroendocrinology ; 113(2): 193-207, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35066506

RESUMO

BACKGROUND: Selenoprotein T (SELENOT), a PACAP-regulated thioredoxin-like protein, plays a role in catecholamine secretion and protects dopaminergic neurons. However, the role of SELENOT in the establishment of the catecholaminergic (CA) neuronal system is not known yet. METHODS: We analyzed by immunohistochemistry and RNAscope in situ hybridization the distribution of SELENOT and the expression of its mRNA, respectively. In addition, 3D imaging involving immunostaining in toto, clearing through the iDISCO+ method, acquisitions by light-sheet microscopy, and processing of 3D images was performed to map the CA neuronal system. A semi-automatic quantification of 3D images was carried out. RESULTS: SELENOT protein and mRNA are widely distributed in the mouse brain, with important local variations. Three-dimensional mapping, through tyrosine hydroxylase (TH) labeling, and semi-automated quantification of CA neurons in brain-specific SELENOT knockout mice showed a significant decrease in the number of TH-positive neurons in the area postrema (AP-A2), the A11 cell group (A11), and the zona incerta (ZI-A13) of SELENOT-deficient females, and in the hypothalamus (Hyp-A12-A14-A15) of SELENOT-deficient females and males. CONCLUSION: These results showed that SELENOT is diffusely expressed in the mouse brain and that its deficiency impacts CA neuron distribution in different brain areas including Hyp-A12-A14-A15, in both male and female mice.


Assuntos
Imageamento Tridimensional , Neurônios , Camundongos , Feminino , Masculino , Animais , Neurônios/metabolismo , Encéfalo/metabolismo , Hibridização In Situ , Camundongos Knockout , RNA Mensageiro/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
4.
Anal Bioanal Chem ; 414(26): 7623-7634, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36063171

RESUMO

Gonadotropin-releasing hormone isoform I (GnRH), a neuro-deca-peptide, plays a fundamental role in development and maintenance of the reproductive system in vertebrates. The anomalous release of GnRH is observed in reproductive disorder such as hypogonadotropic hypogonadism, polycystic ovary syndrome (PCOS), or following prenatal exposure to elevated androgen levels. Quantitation of GnRH plasma levels could help to diagnose and better understand these pathologies. Here, a validated nano-high-performance liquid chromatography-high-resolution mass spectrometry (HPLC-HRMS) method to quantify GnRH in ewe plasma samples is presented. Protein precipitation and solid-phase extraction (SPE) pre-treatment steps were required to purify and enrich GnRH and internal standard (lamprey-luteinizing hormone-releasing hormone-III, l-LHRH-III). For the validation process, a surrogate matrix approach was chosen following the International Council for Harmonisation (ICH) and FDA guidelines. Before the validation study, the validation model using the surrogate matrix was compared with those using a real matrix such as human plasma. All the tested parameters were analogous confirming the use of the surrogate matrix as a standard calibration medium. From the validation study, limit of detection (LOD) and limit of quantitation (LOQ) values of 0.008 and 0.024 ng/mL were obtained, respectively. Selectivity, accuracy, precision, recovery, and matrix effect were assessed with quality control samples in human plasma and all values were acceptable. Sixteen samples belonging to healthy and prenatal androgen (PNA) exposed ewes were collected and analyzed, and the GnRH levels ranged between 0.05 and 3.26 ng/mL. The nano-HPLC-HRMS developed here was successful in measuring GnRH, representing therefore a suitable technique to quantify GnRH in ewe plasma and to detect it in other matrices and species.


Assuntos
Androgênios , Hormônio Liberador de Gonadotropina , Gravidez , Ovinos , Feminino , Animais , Humanos , Projetos Piloto , Hormônio Liberador de Gonadotropina/metabolismo , Cromatografia Líquida de Alta Pressão , Isoformas de Proteínas
5.
Eur J Neurosci ; 46(10): 2596-2607, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28973792

RESUMO

During mammalian embryonic development, GnRH neurones differentiate from the nasal placode and migrate through the nasal septum towards the forebrain. We previously showed that a category of glial cells, the olfactory ensheathing cells (OEC), forms the microenvironment of migrating GnRH neurones. Here, to characterize the quantitative and qualitative importance of this glial, we investigated the spatiotemporal maturation of glial cells in situ and the role of maturing glia in GnRH neurones development ex vivo. More than 90% of migrating GnRH neurones were found to be associated with glial cells. There was no change in the cellular microenvironment of GnRH neurones in the regions crossed during embryonic development as glial cells formed the main microenvironment of these neurones (53.4%). However, the phenotype of OEC associated with GnRH neurones changed across regions. The OEC progenitors immunoreactive to brain lipid binding protein formed the microenvironment of migrating GnRH neurones from the vomeronasal organ to the telencephalon and were also present in the diencephalon. However, during GnRH neurone migration, maturation of OEC to [GFAP+] state (glial fibrillary acid protein) was only observed in the nasal septum. Inducing depletion of OEC in maturation, using transgenic mice expressing herpes simplex virus thymidine kinase driven by the GFAP promoter, had no impact on neurogenesis or on triggering GnRH neurones migration in nasal explant culture. Nevertheless, depletion of [GFAP+] cells decreased GnRH neurites outgrowth by 57.4%. This study suggests that specific maturation of OEC in the nasal septum plays a role in morphological differentiation of GnRH neurones.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Neuritos/fisiologia , Neuroglia/fisiologia , Crescimento Neuronal , Neurônios/fisiologia , Bulbo Olfatório/crescimento & desenvolvimento , Animais , Movimento Celular , Camundongos , Camundongos Transgênicos , Septo Nasal/crescimento & desenvolvimento , Células-Tronco Neurais/fisiologia , Neuroglia/metabolismo , Neurônios/metabolismo , Bulbo Olfatório/metabolismo , Técnicas de Cultura de Órgãos , Células-Tronco , Órgão Vomeronasal/crescimento & desenvolvimento
6.
Stress ; 19(2): 198-205, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26941006

RESUMO

Postnatal treatment with bacterial endotoxin lipopolysaccharide (LPS) changes the activity of the hypothalamic-pituitary-gonadal (HPG) axis and the gonadotropin-releasing hormone (GnRH) surge in rats. Exposure to an immune challenge in the critical periods of development has profound and long-lasting effects on the stress response, immune, metabolic, and reproductive functions. Prenatal LPS treatment delays the migration of GnRH neurons associated with increased cytokine release in maternal and fetal compartments. We investigated the effects of a single maternal exposure to LPS (18 µg/kg, i.p.) on day 12 (embryonic day (E)12) of pregnancy on reproductive parameters in rat offspring. Hypothalamic GnRH content, plasma luteinizing hormone (LH), testosterone, and estradiol concentrations were measured in both male and female offsprings at different stages of postnatal development by RIA and ELISA (n = 10 each per group). Body weight and in females day of vaginal opening (VO) were recorded. In offspring exposed to LPS prenatally, compared with controls, body weight was decreased in both sexes at P5 and P30; in females, VO was delayed; hypothalamic GnRH content was decreased at postnatal days 30-60 (P30-P60) in both sexes; plasma LH concentration was decreased at P14-P60 in females; plasma concentrations of testosterone/estradiol were increased at P14 in females, and plasma estradiol was increased at P14 in males. Hence activation of the maternal immune system by LPS treatment at a prenatal critical period leads to decreased GnRH and LH levels in pre- and postpubertal life and sex steroid imbalance in the prepubertal period, and delayed sexual maturation of female offspring.


Assuntos
Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Exposição Materna , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Animais , Estradiol/sangue , Feminino , Hormônio Liberador de Gonadotropina/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Hipotálamo/metabolismo , Hormônio Luteinizante/sangue , Masculino , Gravidez , Ratos , Testosterona/farmacologia
7.
Therapie ; 70(4): 351-7, 2015.
Artigo em Francês | MEDLINE | ID: mdl-25997721

RESUMO

In Europe, rules relating to the designation and the protection of orphan drug are derived from regulation (EC) 141/2000 of the European Parliament and Council of 16 December 1999, specified by the implementing Regulation (EC) 847/2000. According to these regulations, obtaining the status of orphan drugs implies, in particular, to demonstrate the absence of any satisfying alternative treatment, or, by default, the significant benefit offered by the concerned drug. In the same sense, medicinal product similar to an original orphan medicinal product but safer, more effective or otherwise clinically superior, will benefit from a derogation to the rules on the 10 years market exclusivity usually provided for these products. This article analyses the concept of significant benefit, namely, the clinically relevant advantage or a major contribution to patient care, in particular in the case of similar drugs, as well as the elements to be provided by the sponsor in order to justify this benefit, and the options under which, where there are few or a lack of clinical data on a concerned orphan medicinal products, the demonstration of the significant benefit can rely on assumptions.


Assuntos
Indústria Farmacêutica/legislação & jurisprudência , Produção de Droga sem Interesse Comercial/legislação & jurisprudência , Indústria Farmacêutica/economia , Europa (Continente) , Humanos , Produção de Droga sem Interesse Comercial/economia , Produção de Droga sem Interesse Comercial/normas , Estados Unidos , United States Food and Drug Administration
8.
Glia ; 61(4): 550-66, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23404564

RESUMO

During development, GnRH-1 neurons differentiate extracerebraly from the nasal placode and migrate from the vomeronasal organ to the forebrain along vomeronasal and terminal nerves. Numerous studies have described the influence of different molecules on the migration of GnRH-1 neurons, however, the role of microenvironment cells remains poorly understood. This study used GFAP-GFP transgenic mice to detect glial cells at early developmental stages. Using nasal explant cultures, the comigration of glial cells with GnRH-1 neurons was clearly demonstrated. This in vitro approach showed that glial cells began migrating from the explants before GnRH-1 neurons. They remained ahead of the GnRH-1 migratory front and stopped migrating after the GnRH-1 neurons. The association of these glial cells with the axons combined with gene expression analysis of GFAP-GFP sorted cells enabled them to be identified as olfactory ensheathing cells (OEC). Immunohistochemical analysis revealed the presence of multiple glial cell-type markers showing several OEC subpopulations surrounding GnRH-1 neurons. Moreover, these OEC expressed genes whose products are involved in the migration of GnRH-1 neurons, such as Nelf and Semaphorin 4. In situ data confirmed that the majority of the GnRH-1 neurons were associated with glial cells along the vomeronasal axons in nasal septum and terminal nerves in the nasal forebrain junction as early as E12.5. Overall, these data demonstrate an OEC microenvironment for migrating GnRH-1 neurons during mouse development. The fact that this glial cell type precedes GnRH-1 neurons and encodes for molecules involved in their nasal migration suggests that it participates in the GnRH-1 system ontogenesis.


Assuntos
Movimento Celular/fisiologia , Microambiente Celular/fisiologia , Hormônio Liberador de Gonadotropina/fisiologia , Bulbo Olfatório/citologia , Bulbo Olfatório/embriologia , Mucosa Olfatória/citologia , Mucosa Olfatória/embriologia , Precursores de Proteínas/fisiologia , Animais , Células Cultivadas , Proteína Glial Fibrilar Ácida , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/genética , Bulbo Olfatório/metabolismo , Mucosa Olfatória/metabolismo , Técnicas de Cultura de Órgãos , Regiões Promotoras Genéticas/genética , Coelhos
9.
Therapie ; 67(2): 77-87, 2012.
Artigo em Francês | MEDLINE | ID: mdl-22850095

RESUMO

The Jardé law is adopted further to the Public Health Act No. 2004-806 which transposed into French law the Directive 2001/20/EC on clinical trials of medicinal products, made effective by the implementing Decree 2006-477 of April 26, 2006. The main novelty introduced by the Jardé law is to unify all "research organized and practiced on human beings for the development of biological or medical knowledge" and to facilitate its effective conduct, without however excluding from the scope of the law routine care and non-interventional research. The favorable opinion of the French Ethical Research Committee (comité de protection des personnes or "CCP") will now be required before launching any research on human beings, after validation of the risk/benefit ratio of said research. Applicable requirements and procedures - including information and consent - are adapted to each category of clinical research. New provisions are adopted to address special situations, previously forgotten. Finally, if Ethics committees were up until now freely chosen, they will, in two years' time, be randomly assigned. Thus, the Jardé law amends substantially the legal framework of clinical research in France. The question is whether these new national provisions will be compatible with those from the next revision of the so called "clinical trials" directive 2001/20/EC. In any case, the Jarde law will only come into force when all required implementing measures have been adopted.


Assuntos
Pesquisa Biomédica/legislação & jurisprudência , Ensaios Clínicos como Assunto/legislação & jurisprudência , Legislação Médica/tendências , Saúde Pública/legislação & jurisprudência , Pesquisa Biomédica/ética , Ensaios Clínicos como Assunto/ética , França , Humanos , Consentimento Livre e Esclarecido/legislação & jurisprudência , Legislação Médica/ética , Saúde Pública/ética , Risco , Experimentação Humana Terapêutica
10.
Therapie ; 67(1): 1-10, 2012.
Artigo em Francês | MEDLINE | ID: mdl-22487499

RESUMO

In France, the Médiator(®) scandal and the trauma it has created, are the source of Law n° 2011-2012 of 29 December 2011 on strengthening safety of drug and health products, intended by the Ministry of Labour, Employment and Health, adopted by the National Assembly and promulgated in order to restore confidence and enhance safety of drug and health products. This new law affects all stakeholders and health professionals impacts key points in the life cycle of the drug: MA, reimbursement, advertising, promotion, distribution, prescription, dispensing, and pharmacovigilance. It also provides for financial, administrative or criminal penalties, which are intended deterrent. Beyond strengthening constraints on safety of health products, this new law in France foreshadowed a revolution in behaviour, attitudes and overall scenery of the health system and no one today knows exactly the outline.


Assuntos
Legislação de Medicamentos/tendências , Sistemas de Notificação de Reações Adversas a Medicamentos/organização & administração , Indústria Farmacêutica/legislação & jurisprudência , Indústria Farmacêutica/tendências , Prescrições de Medicamentos/normas , Recall de Medicamento , Fenfluramina/efeitos adversos , Fenfluramina/análogos & derivados , França , Guias como Assunto , Humanos , Farmacovigilância , Segurança
11.
J Chem Neuroanat ; 125: 102149, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36058434

RESUMO

In mammals, reproductive function is under the control of hypothalamic neurons named Gonadotropin-Releasing Hormone (GnRH) neurons. These neurons migrate from the olfactory placode to the brain, during embryonic development. For the past 40 years, these neurons have been considered an example of tangential migration, i.e., dependent on the olfactory/vomeronasal/terminal nerves. Numerous studies have highlighted the factors involved in the migration of these neurons but thus far overlooked the cellular microenvironment that produces them. Many of these factors are dysregulated in hypogonadotropic hypogonadism, resulting in subfertility/infertility. Nevertheless, over the past ten years, several papers have reported the influence of glial cells (named olfactory ensheathing cells [OECs]) in the migration and differentiation of GnRH neurons. This review will describe the atypical origins, migration, and differentiation of these neurons, focusing on the latest discoveries. There will be a more specific discussion on the involvement of OECs in the development of GnRH neurons, during embryonic and perinatal life; as well as on their potential implication in the development of congenital or idiopathic hypogonadotropic hypogonadism (such as Kallmann syndrome).


Assuntos
Hormônio Liberador de Gonadotropina , Síndrome de Kallmann , Animais , Adulto , Humanos , Movimento Celular/fisiologia , Neuroglia , Neurônios/fisiologia , Mamíferos
12.
J Chem Neuroanat ; 114: 101944, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33716103

RESUMO

Since the early eighties MRI has become the most powerful technic for in-vivo imaging particularly in the field of brain research. This non-invasive method allows acute anatomical observations of the living brain similar to post-mortem dissected tissues. However, one of the main limitation of MRI is that it does not make possible the neurochemical identification of the tissues conversely to positron emission tomography scanner which can provide a specific molecular characterization of tissue, in spite of poor anatomical definition. To gain neurochemical information using MRI, new categories of contrast agents were developed from the beginning of the 2000's, particularly using the chemical-exchange saturation transfer (CEST) method. This method induces a significant change in the magnitude of the water proton signal and allows the detection of specific molecules within the tissues like sugars, amino acids, transmitters, and nucleosides. This short review presents several CEST contrast agents and their recent developments for in vivo detection of metabolites and neurotransmitters in the brain for research and clinical purposes.


Assuntos
Química Encefálica , Meios de Contraste , Imageamento por Ressonância Magnética/métodos , Imagem Molecular/métodos , Neuroimagem/métodos , Animais , Humanos
13.
J Am Soc Nephrol ; 20(6): 1282-92, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19470687

RESUMO

Invariant natural killer T (iNKT) cells represent a particular subset of T lymphocytes capable of producing several cytokines, which exert regulatory or effector functions, following stimulation of the T cell receptor. In this study, we investigated the influence of iNKT cells on the development of experimental anti-glomerular basement membrane glomerulonephritis (anti-GBM GN). After injection of anti-GBM serum, the number of kidney iNKT cells rapidly increased. iNKT cell-deficient mice (Jalpha18-/-) injected with anti-GBM serum demonstrated worse renal function, increased proteinuria, and greater glomerular and tubular injury compared with similarly treated wild-type mice. We did not detect significant differences in Th1/Th2 polarization in renal tissue that might have explained the severity of disease in Jalpha18-/- mice. Interestingly, expression of both TGF-beta and TGF-beta-induced (TGFBI) mRNA was higher in wild-type kidneys compared with Jalpha18-/- kidneys, suggesting a possible protective role for TGF-beta in anti-GBM GN. Administration of an anti-TGF-beta neutralizing antibody significantly enhanced the severity of disease in wild-type, but not Jalpha18-/-, mice. In conclusion, in experimental anti-GBM GN, iNKT cells attenuate disease severity and TGF-beta has a renoprotective role.


Assuntos
Doença Antimembrana Basal Glomerular/imunologia , Rim/patologia , Células T Matadoras Naturais/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Doença Antimembrana Basal Glomerular/metabolismo , Anticorpos Monoclonais , Proteínas da Matriz Extracelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Linfócitos T Auxiliares-Indutores/metabolismo , Fator de Crescimento Transformador beta/imunologia
14.
Eur J Neurosci ; 30(4): 639-50, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19659454

RESUMO

In sheep, the onset of filial bonding relies on early intake of colostrum. The aim of our work was to describe in the newborn lamb housed with its mother the immediate post-ingestive effects of colostrum intake, in terms of behaviour and brain activity. In Experiment 1, lambs received five nasogastric infusions of colostrum, or saline, or sham intubations during the first 6 h after birth. Mother-young interactions were recorded before and after the first, third and fifth infusions. The activity of the dam and of the young, which diminished over time in all groups, was temporarily increased in both partners just after each intubation procedure. The number of high-pitched bleats was significantly lower in lambs that received colostrum than in the sham group, suggesting soothing or satiating properties of colostrum. In Experiment 2, newborn lambs received a single nasogastric infusion of colostrum or saline 4.5 h after birth, or were sham intubated. Neuronal activation was investigated 1.5 h later for maximum c-Fos activity. Infusion of colostrum and saline induced different patterns of c-Fos-like immunoreactivity in the paraventricular and supraoptic nuclei of the hypothalamus as compared with the sham group. A specific oxytocinergic/vasopressinergic (OT/VSP) cell population in the paraventricular nucleus was activated following colostrum and saline infusion, but not sham intubation. Only colostrum induced the activation of the cortical amygdala and insular cortex, two structures involved in learning, associative processes, reward and emotion. We hypothesize that filial bonding may be triggered through colostrum-rewarded learning/calming processes and that the OT/VSP system may play a role.


Assuntos
Comportamento Animal/fisiologia , Encéfalo/metabolismo , Colostro/fisiologia , Comportamento Materno/fisiologia , Apego ao Objeto , Animais , Animais Recém-Nascidos , Contagem de Células , Ingestão de Alimentos/fisiologia , Feminino , Imuno-Histoquímica , Lactação/fisiologia , Masculino , Neurofisinas/metabolismo , Gravidez , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ovinos , Coloração e Rotulagem , Tirosina 3-Mono-Oxigenase/metabolismo
15.
J Chem Neuroanat ; 35(3): 257-67, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18282688

RESUMO

The present study was designed to determine the changes in the synthesis, storage and release of luteinising hormone (LH) and growth hormone (GH) in the hypophyseal cells by investigating the presence of oestrogen receptor-alpha (ERalpha) in developing prepubertal female lambs. The experiment was carried out on 14 prepubertal (17-week-old) and 14 peripubertal (32-week-old) ovary-intact lambs. Morphofunctional changes in the cells of the adenohypophyseal population were assayed with immunohistochemistry (IH), in situ hybridisation (ISH), Real-time PCR and radioimmunoassay (RIA). Blood samples (n=14) were taken every 2 weeks from 17 to 32 weeks of age for estimation of GH and LH by RIA. Computer image analysis was used to determine the percent of cells exhibiting IH and/or ISH reaction. The percentage of cells stained for LHbeta and GH increased for both LH- and GH-producing cells and were higher (P<0.001) in the peripubertal than prepubertal group. The percentage of mRNA LHbeta-expressing cells decreased and were lower for the peripubertal (P<0.001) than prepubertal group. The GH mRNA in pituitaries of prepubertal lambs was higher in comparison to peripubertal ones (P<0.001). The percentage of ERalpha positive cells increased significantly (P<0.001) in peripubertal compared to prepubertal lambs and this increase was significant (P<0.001) in both LH- and GH-producing cells. Plasma LH concentrations increased from 27 weeks of age, while GH concentrations gradually decreased from 17 weeks of age (P<0.05). The histomorphological changes in the LH- and GH-producing cells reflect the increasing pattern of the regulation of secretory processes of these hormones and an escalating regulatory role of oestrogen in the physiology of these cells during the prepubertal period. These results support the involvement of both hormones in the events leading up to puberty.


Assuntos
Receptor alfa de Estrogênio/metabolismo , Hormônio do Crescimento/metabolismo , Hormônio Luteinizante/metabolismo , Hipófise/metabolismo , Animais , Feminino , Hormônio do Crescimento/biossíntese , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Hibridização In Situ , Hormônio Luteinizante/biossíntese , Hipófise/citologia , Hipófise/ultraestrutura , Adeno-Hipófise/citologia , Adeno-Hipófise/metabolismo , Adeno-Hipófise/ultraestrutura , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ovinos
16.
J Chem Neuroanat ; 36(1): 53-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18603404

RESUMO

It is assumed that hypothalamic somatostatin plays a role in the preovulatory phase of the oestrous cycle in sheep. The aim of the study was to investigate the processes of synthesis, storage and release of somatostatin in hypothalamic neurons, in immature female lambs, in the period approaching to puberty. Experiments were carried out on 10 prepubertal (17 weeks old) and 10 peripubertal (32 weeks old) ovary-intact lambs. Morphofunctional changes in the somatostatin neurons were assayed with immunohistochemistry and hybridisation in situ. Computer image analysis was used to determine the density of both reactions and the percentage of the area exhibiting immunohistochemical staining. These parameters express the content of immunoreactive (ir) somatostatin and expression of mRNA for pre-pro-somatostatin (PPS). Two populations of ir somatostatin perikarya were localized in the hypothalamus: a very large number of perikarya in the periventricular (PEV) nucleus, and single cell bodies in the arcuate (ARC) nucleus. Only ir somatostatin fibres, but no perikarya were seen in the ventromedial (VM) nucleus and preoptic area. The analysis of mRNA PPS showed perikarya filled with silver grains localized in the PEV, ARC and VM. There were differences in the content of ir somatostatin and the intensity of the PPS mRNA signal between the two periods investigated. In the median eminence, the content of ir somatostatin in the terminals decreased in the peripubertal compared to the prepubertal group (P<0.001). In the PEV, the content of ir somatostatin in the perikarya and the expression of PPS mRNA decreased in the peripubertal compared to the prepubertal group (P<0.001). In the ARC, the content of ir somatostatin in the perikarya increased (P<0.001), but expression of PPS mRNA decreased (P<0.001) in the peripubertal compared to the prepubertal group. There were no differences in the expression of PPS mRNA in the VM. We concluded, that the different secretory activity of the two hypothalamic populations of somatostatin neurons can be related to their different physiological functions in the prepubertal period of female lambs.


Assuntos
Hipotálamo/crescimento & desenvolvimento , Hipotálamo/metabolismo , Maturidade Sexual/fisiologia , Somatostatina/metabolismo , Animais , Ciclo Estral/metabolismo , Feminino , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Hibridização In Situ , Ovinos
17.
Brain Res ; 1223: 34-41, 2008 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-18597744

RESUMO

The aim of the present study was to explore the putative effects of agonists and antagonists of the estradiol receptor on the early phase of GnRH-1 neuron development. To address this question we used an in vitro model of GnRH-1 neurons using cultured olfactory placode from sheep embryos on day 26 of gestation. Previous studies on this model have shown that in vitro the development of GnRH-1 neurons mimics in vivo development up to the start of pulsatile GnRH-1 secretion, To address the effects of modulating the estrogen receptor, cultures were treated with the endogenous and synthetic ligands of estradiol receptors: 17beta-estradiol, 17alpha-estradiol and tamoxifen. Neurogenesis was measured by incorporation of [(3)H]-thymidine. Morphometric parameters were evaluated by image analysis. The main results are that antagonism of estradiol receptors induced an important decrease in neurogenesis but had little effect on morphometric parameters, suggesting that during this early phase of development, maternal estrogens are important to achieve correct development of the GnRH-1 neuronal network.


Assuntos
Diferenciação Celular/fisiologia , Hormônio Liberador de Gonadotropina/metabolismo , Neurônios/metabolismo , Mucosa Olfatória/embriologia , Precursores de Proteínas/metabolismo , Receptores de Estrogênio/metabolismo , Células-Tronco/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Proliferação de Células , Células Cultivadas , Estradiol/metabolismo , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Feminino , Troca Materno-Fetal/fisiologia , Rede Nervosa/citologia , Rede Nervosa/embriologia , Rede Nervosa/metabolismo , Neurônios/citologia , Neurônios/efeitos dos fármacos , Mucosa Olfatória/citologia , Mucosa Olfatória/metabolismo , Condutos Olfatórios/citologia , Condutos Olfatórios/embriologia , Condutos Olfatórios/metabolismo , Gravidez , Área Pré-Óptica/citologia , Área Pré-Óptica/embriologia , Área Pré-Óptica/metabolismo , Receptores de Estrogênio/agonistas , Receptores de Estrogênio/antagonistas & inibidores , Carneiro Doméstico , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Tamoxifeno/farmacologia
18.
Brain Struct Funct ; 223(7): 3297-3316, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29869133

RESUMO

The periaqueductal gray (PAG) is a mesencephalic brain structure organised in subdivisions with specific anatomical connections with the rest of the brain. These connections support the different PAG functions and especially its role in emotion. Mainly described in territorial and predatory mammals, examination of the PAG connections suggests an opposite role of the ventral and the dorsal/lateral PAG in passive and active coping style, respectively. In mammals, the organisation of PAG connections may reflect the coping style of each species. Based on this hypothesis, we investigated the anatomical connections of the PAG in sheep, a gregarious and prey species. Since emotional responses expressed by sheep are typical of active coping style, we focused our interest on the dorsal and lateral parts of the PAG. After injection of fluorogold and fluororuby, the most numerous connections occurred with the anterior cingulate gyrus, the anterior hypothalamic region, the ventromedial hypothalamic nucleus and the PAG itself. Our observations show that the sheep PAG belongs to the neuronal circuit of emotion and has specific parts as in other mammals. However, unlike other mammals, we observed very few connections between PAG and either the thalamic or the amygdalar nuclei. Interestingly, when comparing across species, the PAG connections of sheep were noticeably more like those previously described in other social species, rabbits and squirrel monkeys, than those in territorial species, rats or cats.


Assuntos
Comportamento Animal , Emoções , Neurônios/fisiologia , Substância Cinzenta Periaquedutal/fisiologia , Animais , Dextranos/administração & dosagem , Feminino , Corantes Fluorescentes/administração & dosagem , Vias Neurais/fisiologia , Técnicas de Rastreamento Neuroanatômico , Marcadores do Trato Nervoso/administração & dosagem , Substância Cinzenta Periaquedutal/citologia , Rodaminas/administração & dosagem , Carneiro Doméstico , Comportamento Social , Especificidade da Espécie , Estilbamidinas/administração & dosagem
19.
Drugs Aging ; 24(11): 957-65, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17953462

RESUMO

BACKGROUND: Xerostomia is a subjective sensation of mouth dryness that may frequently occur in older patients. OBJECTIVE: To compare the clinical efficacy and acceptability of a new oxygenated glycerol triester (OGT) oral spray taken five times daily with that of a commercially available saliva substitute Saliveze in the treatment of xerostomia. METHODS: Forty-one institutionalised patients (28 women, 13 men; mean age 84 +/- 7 years) were randomly assigned to receive either OGT or Saliveze in a 2-week, randomised, parallel-group study. Clinical assessment of xerostomia included evaluation of mouth dryness using a self-rated, 10cm long visual analogue scale (VAS), objective assessment of oral tissue condition using a four-point ordinal scale and subjective assessment of symptoms of xerostomia using dichotomous responses to a questionnaire. The primary endpoint was the day (D) 14 patient-based mouth dryness score measured on a self-rated VAS. RESULTS: At D14, OGT resulted in significantly greater efficacy with respect to mouth dryness (mean between-treatment difference 2.1 +/- 0.1, 95% CI 1.9, 2.3; p = 0.001), swallowing difficulty (1.8 +/- 0.3, 95% CI 1.5, 2.1; p = 0.001), speech difficulty (1.1 +/- 0.2, 95% CI 1.0, 2.4; p = 0.04) and overall sensation of symptom relief (2.7 +/- 1.2, 95% CI 1.9, 3.8; p = 0.001). Objective assessment of oral tissues also showed significantly better improvement with OGT spray with respect to dryness (p = 0.01), stickiness (p = 0.005) and dullness (p = 0.001) of oral mucosa; severity of mucositis (p = 0.01); and thickening of the tongue (p = 0.03). A significant difference in taste acceptability was also noted in favour of OGT (1.4 +/- 0.6, 95% CI 1.2, 1.9; p = 0.04). CONCLUSION: OGT lubricant oral spray was superior to Saliveze in improving xerostomia and oral tissue condition in older institutionalised patients.


Assuntos
Idoso/fisiologia , Glicerol/uso terapêutico , Lubrificantes/uso terapêutico , Xerostomia/tratamento farmacológico , Administração Oral , Aerossóis , Idoso de 80 Anos ou mais , Método Duplo-Cego , Determinação de Ponto Final , Feminino , Glicerol/administração & dosagem , Glicerol/efeitos adversos , Hospitalização , Humanos , Assistência de Longa Duração , Lubrificantes/administração & dosagem , Lubrificantes/efeitos adversos , Masculino , Boca/patologia , Soluções Farmacêuticas , Inquéritos e Questionários , Resultado do Tratamento , Xerostomia/patologia
20.
J Chem Neuroanat ; 125: 102161, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36100131

Assuntos
Encéfalo , Hipotálamo
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