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Effect of early luteolysis in progesterone-based Al protocols in Bos indicus, Bos indicus x Bos taurus and Bos taurus heifers

CARVALHO, J. B. P.; CARVALHO, N. A. T.; REIS, E. L.; NICHI, M.; SOUZA, A. H.; BARUSELLI, P. S.
Fonte: ELSEVIER SCIENCE INC Publicador: ELSEVIER SCIENCE INC
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.98%
The objective of this study was to evaluate the effects of treatment with an intravaginal progesterone-releasing device (CIDR) and estradiol benzoate (EB) on follicular dynamics in Bos indicus (n = 23), Bos taurus (n = 25), and cross-bred (n = 23) heifers. To assess the influence of reduced serum progesterone concentrations during 8 days of treatment with a progesterone-releasing device on follicular dynamics, half of the heifers received PGF at CIDR insertion (Day 0; 3 x 2 factorial design). Mean ( +/- S.E.M.) serum progesterone concentrations during CIDR treatment varied (P < 0.05) among genetic groups: B. indicus (5.4 +/- 0.1 ng/mL), B. taurus (3.3 +/- 0.0 ng/mL), and cross-bred (4.3 +/- 0.1 ng/mL). Maximum diameter of the dominant follicle (DF) was smaller (P < 0.01) in B. indicus heifers (9.5 +/- 0.5 mm) than in cross-bred (12.3 +/- 0.4 mm) or B. taurus heifers (11.6 +/- 0.5 mm). B. indicus experienced lower (P < 0.01) ovulation rate (39.1%) than did B. taurus (72.7%) and cross-bred (84.0%). Heifers treated with PGF on Day 0 had lower (P < 0.05) serum progesterone concentrations during progesterone treatment. The PGF treatment on Day 0 increased (P < 0.01) the diameter of the DF (11.9 +/- 0.4 mm vs. 10.5 +/- 0.4 mm). Moreover...

Emprego de matriz polimérica biodegradável em dispositivos vaginais para liberação sustentada de progesterona em fêmeas bovinas: testes in vitro e in vivo; Use of biodegradable polymeric matrix, in vaginal devices, to sustained progesterone release in cows: in vitro e in vivo tests

Pimentel, José Rodrigo Valim
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 26/06/2006 Português
Relevância na Pesquisa
37%
Com o aumento do número de animais inseminados por IATF (inseminação artificial em tempo fixo), a diminuição de custos e o incremento de índices reprodutivos têm sido os objetivos de vários grupos de pesquisa. Nos protocolos de IATF utilizados, empregam-se dispositivos de liberação sustentada de progesterona (P4), que são, em sua maioria, constituídos de um esqueleto de nylon, recoberto com uma camada de silicone com P4 . Visando a diminuição dos custos de produção e impacto ambiental, foi desenvolvido um dispositivo à base de biopolímeros. Neste estudo, foram comparados dispositivos confeccionados com uma blenda constituída de Poli-hidroxi-butirato (PHB) e Poli-&epsion;-caprolactona (PCL), com o Dispositivo Interno Bovino (DIB®), utilizado como controle . No teste in vitro, utilizaram-se dois tipos de dispositivo à base de biopolímeros, com uma área superficial de 147 cm2: DISP8 (46% PHB, 46% PCL e 8% P4; n=4), DISP10 (45% PHB, 45% PCL, 10% P4; n=4) e o DIB® (1 g de P4, área de 120 cm2; n=3). Os testes in vitro foram conduzidos segundo especificações da USP 23, em um dissolutor de comprimidos, empregando-se uma mistura de álcool/água (60/40) como meio de difusão. Amostras do meio foram colhidas aos 2 min....

Perfil da secreção de progesterona em ratas no proestro: uma nova proposta para o controle do pico pré-ovulatório de LH; A new proposal for the progesterone control of Luteinizing Hormone surge during proestrus

Callegari, Fernanda Vieira Rodovalho
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 04/12/2008 Português
Relevância na Pesquisa
37.1%
A ocorrência do pico pré-ovulatório de LH no proestro depende da pré-exposição aos estrógenos seguida da ação aguda da progesterona, hormônio responsável pela deflagração e amplitude desse pico. No entanto, a origem da progesterona durante essa fase do ciclo ainda é incerta. Enquanto alguns estudos sugerem que a adrenal contribui significativamente para secreção de progesterona nesse período, outros apontam a ovário como a fonteprincipal. Sendo assim, o objetivo desse trabalho foi estudar o perfil e a origem da secreção de progesterona durante o proestro e a sua relação com o pico pré-ovulatório de LH. Para tanto, às 7h00 da manhã do proestro ratas Wistar adultas foram submetidas apenas à canulação da veia jugular (controle) ou a esse procedimento seguido pela cirurgia fictícia de retirada do ovário e adrenal (Sham), oupela ovariectomia (OVX) ou pela adrenalectomia (ADX). Amostras sanguíneas foram coletadas a cada 15 minutos das 11h00 às 13h45 para dosagem de progesterona, estradiol e corticosterona e a cada hora das 14h00 às 19h00 para dosagem desses três hormônios e do LH. Adicionalmente, 7 dias depois da ovariectomia, ratas foram tratadas com óleo milho (OVO) ou 17-?-estradiol (OVE) por 3 dias consecutivos...

Utilização de progesterona injetável de longa ação no manejo reprodutivo de fêmeas bovinas de corte; Use of long-acting progesterone on reproductive management of beef cows

Rocha, Dimas Corrêa
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Tese de Doutorado Formato: application/pdf
Português
Relevância na Pesquisa
37.11%
O objetivo deste estudo foi determinar a farmacocinética de uma solução injetável de progesterona concentrada de longa ação. A partir deste conhecimento, elaborar novos experimentos para testar a funcionalidade do produto em protocolos de sincronização de estro e posteriormente avaliar seus efeitos na esfera reprodutiva da fêmea bovina. O experimento 1 determinou a concentração de progesterona plasmática ao longo do tempo a partir do tratamento com uma solução injetável de progesterona concentrada de longa ação (MAD4®), variando a dose e a via de administração, no sentido de demonstrar a farmacocinética do produto. Foram utilizadas 08 vacas Braford ovariectomizadas. A concentração de progesterona utilizada nos tratamentos 1 e 2 foi 250mg por via IM e SC. No tratamento 3 utilizou-se dose de 375mg de progesterona SC. O experimento 2 analisou o efeito de um tratamento hormonal com progesterona em vacas de corte em anestro pós-parto, avaliando a dinâmica folicular, níveis plasmáticos de progesterona e taxa de prenhez final. Foram utilizadas 09 vacas Braford. O grupo controle (n=4) recebeu no dia 0 estradiol 2mg IM e 7 dias depois PGF2alfa. O grupo tratamento (n=5) recebeu o mesmo protocolo com a adição de 250mg SC de progesterona no dia 0. Todas as vacas foram entouradas a partir do dia 7. O experimento 3 avaliou a sincronização de estros e a taxa de prenhez em novilhas de corte previamente tratadas com progesterona...

Acute reduction in serum progesterone concentrations after feed intake in dairy cows

Vasconcelos, J. L M; Sangsritavong, S.; Tsai, S. J.; Wiltbank, M. C.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 795-807
Português
Relevância na Pesquisa
37.05%
This study tested the hypothesis that high feed consumption will acutely decrease circulating progesterone concentrations. In the first experiment, a Latin Square design was used to test whether feeding pattern would alter circulating progesterone in pregnant lactating Holstein cows (n = 12). Feed was removed for 12 h before the experiment and cows were then either fed 100% of the total mixed ration (TMR), 50% of TMR every 12 h, 25% of TMR every 6 h, or left unfed for an additional 12 h. Blood samples were taken every hour for 24 h. Provision of 100 or 50% of TMR decreased circulating progesterone by 1 h after feeding and progesterone remained depressed until 8-9 h after feeding. Feeding 25% of TMR did not reduce circulating progesterone concentrations. Experiment 2 used a crossover design to measure the effect of acute feeding on circulating progesterone and LH concentrations during delivery of a constant amount of exogenous progesterone (Eazi-Breed CIDRs) in lactating Holstein cows (n = 8) and nonpregnant dry Holstein cows (n = 6). Blood samples were taken every 15 min for 8 h. There was no change in serum progesterone during the 8 h treatment period in unfed cows; however, feeding decreased (P < 0.05) circulating progesterone between 2 and 6 h after feeding. In lactating cows...

Progesterone restores the female prostate activity in ovariectomized gerbil and may act as competitor of testosterone in intraprostatic environment

Shinohara, Filipe Z.; Silva, Diego A.L.; Zanatelli, Marianna; Góes, Rejane M.; Vilamaior, Patricia S.L.; Santos, Fernanda C.A.; Taboga, Sebastião R.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 957-966
Português
Relevância na Pesquisa
37.01%
Aims Little is known about the effect of progesterone on gerbil female prostate. It is known that normal oscillation in the progesterone and estradiol levels during the estrous cycle phases influence the morphophysiology of this gland. The present study aims to evaluate the isolated effect of prolonged administration of progesterone combined or not with testosterone on the prostate of ovariectomized female gerbil. Main methods To observe the morphological changes caused by castration in the prostate of different groups stereologic analyses of all prostate compartments, analysis of nuclear area and perimeter, and morphometric measurements of epithelial and smooth muscle cells layers were used. In addition, immunocytochemistry was performed to investigate the distribution of the androgen, estrogen alfa and beta and progesterone receptors in different prostatic compartments. Key findings This study demonstrated that both treatments partially recovered the structure of the gland. In the group treated with progesterone plus testosterone a higher incidence of epithelial and stromal disorders occurred, besides the absence of secretory activity. Thus, treatment only with progesterone showed better results in the restoration of glandular homeostasis mainly seen by the regulation of the secretory activity. Significance Collectively...

Influência da progesterona sobre a próstata do gerbilo (Meriones unguiculatus) : interações com o estrógeno e com a testosterona = Progesterone influence on gerbil (Meriones unguiculatus) prostat e: interactions with estrogen and testosterone; Progesterone influence on gerbil (Meriones unguiculatus) prostate : interactions with estrogen and testosterone

Ricardo Alexandre Fochi
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 25/02/2013 Português
Relevância na Pesquisa
37.07%
A próstata, glândula do sistema genital que tem origem embrionária a partir do seio urogenital, não é exclusiva do sistema reprodutor masculino, sendo também encontrada em fêmeas de vários mamíferos, incluindo humanos e roedores. No macho ela pode apresentar-se altamente desenvolvida em razão da maior quantidade do hormônio testosterona, e, apesar de pouco desenvolvida em fêmeas, devido à baixa quantidade desse mesmo tipo hormonal, é uma glândula funcional. Em fêmeas adultas de gerbilos, a próstata possui uma localização parauretral, exibindo íntimo contato com a parede proximal e medial da uretra, a qual é homóloga a próstata ventral de roedores machos. Embora se conheça a influência da progesterona na fisiologia do sistema reprodutor feminino e masculino, poucos estudos exploram a sua influência, especificamente, sobre a glândula prostática. Desta forma, este trabalho avaliou os aspectos morfofuncionais da glândula prostática masculina e feminina, resultantes da influência da progesterona, e de suas interações com o estradiol e a testosterona. Para isso, gerbilos machos e fêmeas foram castrados cirurgicamente no início do período puberal, aos 45 dias de idade. Ao completarem 90 dias de idade, os gerbilos receberam doses subcutâneas de progesterona ou desse somado a estradiol e testosterona...

Progesterone and Follicle Stimulating Hormone interact and promote goat preantral follicles survival and development in vitro

Lima-Verde,Isabel B.; Matos,Maria H.T.; Celestino,Juliana J.H.; Rossetto,Rafael; Name,Khesller P.O.; Báo,Sônia N.; Campello,Cláudio C.; Figueiredo,José R.
Fonte: Colégio Brasileiro de Patologia Animal - CBPA; Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Publicador: Colégio Brasileiro de Patologia Animal - CBPA; Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA)
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2012 Português
Relevância na Pesquisa
37.03%
We investigated the effects of progesterone and follicle stimulating hormone (FSH) on survival and growth of caprine preantral follicles. Pieces of ovarian tissue were cultured for 1 or 7 days in minimum essential medium (MEM) alone or containing progesterone (1, 2.5, 5, 10 or 20ng/mL), FSH (50ng/mL) or the interaction between progesterone and FSH. Fresh (non-cultured control) and cultured ovarian tissues were processed for histological and ultrastructural studies. After 7 days the addition of FSH to all progesterone concentrations maintained the percentage of normal follicles similar to fresh control. At day 7 of culture, a higher percentage of developing follicles was observed only in 2.5ng/ml of progesterone associated with FSH or 10ng/ml of progesterone alone when compared with control. From day 1 to day 7 of culture, a significant increase in the percentage of developing follicles was observed in MEM and 2.5ng/ml of progesterone + FSH. In addition, after 7 days, in all treatments, there was a significant increase in follicular diameter when compared with control, except for MEM alone and in 5ng/ml of progesterone + FSH or 10ng/ml of progesterone alone. Ultrastructural studies confirmed follicular integrity after 7 days of culture in 2.5ng/ml of progesterone with FSH. In conclusion...

Dietary manipulation of local versus systemic progesterone and effects on embryo survival and litter size in gilts.

Athorn, Rebecca Zoe
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2013 Português
Relevância na Pesquisa
37%
Progesterone is an important driver of endometrial function and as such plays an important role in early embryo development, implantation and survival. High feeding levels during early pregnancy in gilts usually result in a decrease in the concentration of progesterone in systemic blood circulation, through an increase in hepatic metabolism, and have as a consequence been associated with a reduction in embryo survival. However, effects of feeding level on embryo survival have been equivocal with some studies finding no, or even, positive effects of an increased feeding level on embryo survival. This paradox may be due to an underestimated supply of ‘local’ progesterone (directly from the ovary to the uterus), which may be enhanced at a higher feed level. This thesis proves the importance of the contribution of this local source of progesterone for embryo survival, using a unilateral ovariectomy model, and that progesterone concentrations in the venous drainage from the reproductive organs actually increases at higher feeding levels. Across all studies presented in this thesis a high feed level was not detrimental to embryo survival and was actually beneficial in some studies. Ovarian production of progesterone may also be increased in animals on a high feed level...

Use of progesterone treatment for the prevention of recurrent preterm birth: identification of obstacles to change

Lim, A.; Goossens, A.; Ravelli, A.; Boer, K.; Bruinse, H.; Mol, B.
Fonte: Thieme Medical Publishers Publicador: Thieme Medical Publishers
Tipo: Artigo de Revista Científica
Publicado em //2010 Português
Relevância na Pesquisa
36.98%
Progesterone treatment has proven to be effective in preventing recurrent preterm birth. The use of progesterone varies widely between different obstetric clinics in the Netherlands. The study aimed to identify factors that hamper or facilitate the use of progesterone to create an implementation strategy. A Web-based survey was developed containing questions on sociopolitical factors, organizational factors, knowledge, and attitude. This survey was spread among 212 gynecologists, 203 midwives, and 130 women with a recent preterm birth. Response rates were 46% for gynecologists, 57% for midwives, and 78% for patients. Twenty-five percent of gynecologists were prescribing progesterone, 21% of midwives would recommend progesterone, and 54% of patients were willing to undergo treatment in future pregnancies. Specific factors hampering implementation for gynecologists were working in nonteaching hospitals and absence of progesterone treatment in local protocols. For midwives and patients, unfamiliarity with progesterone was the most notable finding. The major reason for failure of implementation of progesterone treatment to prevent recurrent preterm birth is absence of this treatment in protocols and lack of familiarity with this treatment in midwives and patients. This may be overcome through adjustment of clinical protocols on regional and national levels.; Arianne C. Lim...

Lymphokines, including interleukin-2, alter gonadotropin-stimulated progesterone production and proliferation of human granulosa-luteal cells in vitro

Wang, L.; Robertson, S.A.; Seamark, R.F.; Norman, R.J.
Fonte: Endocrine Society Publicador: Endocrine Society
Tipo: Artigo de Revista Científica
Publicado em //1991 Português
Relevância na Pesquisa
37.04%
The effects of human interleukin-1 (IL-1) and IL-2 on human granulosa-luteal cell progesterone production were examined with or without hCG stimulation in vitro. Human granulosa-luteal cells were recovered from follicular fluid obtained from women undergoing in vitro fertilization procedures and cultured for up to 7 days before supernatant progesterone level measurement. Lymphokine-rich conditioned medium was prepared from mitogen-stimulated human peripheral blood leukocytes (HPL-CM). The influence of HPL-CM on both granulosa-luteal cell progesterone production and cell growth was inhibitory. In contrast, supernatants of the IL-2-producing cell line MLA-144 (MLA-CM) stimulated both basal progesterone secretion and cell proliferation. Human recombinant IL-2 (from 0.1-100 IU) alone did not change progesterone levels, compared to control values, after 24 h of cell culture. However, 1, 10, and 100 IU IL-2 significantly inhibited progesterone secretion from cells stimulated by 5 IU hCG (P less than 0.01). The enhanced progesterone levels stimulated by forskolin were also significantly inhibited by 10 IU IL-2 (P = 0.01). This effect was not mediated through decreased cAMP, since the forskolin-enhanced cAMP level was not influenced by IL-2...

Prenatal administration of progesterone for preventing preterm birth in women considered to be at risk of preterm birth

Dodd, J.; Jones, L.; Flenady, V.; Cincotta, R.; Crowther, C.
Fonte: Update Software Ltd Publicador: Update Software Ltd
Tipo: Artigo de Revista Científica
Publicado em //2013 Português
Relevância na Pesquisa
37.08%
BACKGROUND Preterm birth is a major complication of pregnancy associated with perinatal mortality and morbidity. Progesterone for the prevention of preterm labour has been advocated. OBJECTIVES To assess the benefits and harms of progesterone for the prevention of preterm birth for women considered to be at increased risk of preterm birth and their infants. SEARCH METHODS We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (14 January 2013) and reviewed the reference list of all articles. SELECTION CRITERIA Randomised controlled trials, in which progesterone was given for preventing preterm birth. DATA COLLECTION AND ANALYSIS Two review authors independently evaluated trials for methodological quality and extracted data. MAIN RESULTS Thirty-six randomised controlled trials (8523 women and 12,515 infants) were included. Progesterone versus placebo for women with a past history of spontaneous preterm birth Progesterone was associated with a statistically significant reduction in the risk of perinatal mortality (six studies; 1453 women; risk ratio (RR) 0.50, 95% confidence interval (CI) 0.33 to 0.75), preterm birth less than 34 weeks (five studies; 602 women; average RR 0.31, 95% CI 0.14 to 0.69), infant birthweight less than 2500 g (four studies; 692 infants; RR 0.58...

Prenatal administration of progesterone for preventing preterm birth

Dodd, J.; Flenady, V.; Cincotta, R.; Crowther, C.
Fonte: Update Software Ltd Publicador: Update Software Ltd
Tipo: Artigo de Revista Científica
Publicado em //2006 Português
Relevância na Pesquisa
37%
BACKGROUND: Preterm birth is the major complication of pregnancy associated with perinatal mortality and morbidity and occurs in up to 6% to 10% of all births. Administration of progesterone for the prevention of preterm labour has been advocated. OBJECTIVES: To assess the benefits and harms of progesterone administration during pregnancy in the prevention of preterm birth. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group's Specialised Register of Controlled Trials (March 2005), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 3, 2004), MEDLINE (1965 to January 2005), EMBASE (1988 to August 2004), and Current Contents (1997 to August 2004). SELECTION CRITERIA: All published and unpublished randomised controlled trials, in which progesterone was given by any route for preventing preterm birth. DATA COLLECTION AND ANALYSIS: Standard methods of the Cochrane Collaboration and the Cochrane Pregnancy and Childbirth Group were used. Evaluation of methodological quality and trial data extraction were undertaken independently by two authors. Results are presented using relative risk with 95% confidence intervals. MAIN RESULTS: For all women administered progesterone, there was a reduction in the risk of preterm birth less than 37 weeks (six studies...

Fetoplacental growth in sheep administered progesterone during the first three days of pregnancy

Kleemann, D.; Walker, S.; Hartwich, K.; Fong, L.; Seamark, R.; Robinson, J.; Owens, J.
Fonte: W B Saunders Co Ltd Publicador: W B Saunders Co Ltd
Tipo: Artigo de Revista Científica
Publicado em //2001 Português
Relevância na Pesquisa
37.01%
We have previously shown that administration of progesterone during early pregnancy in sheep enhances fetal weight and crown–rump length. The present study examined the effect of this treatment on individual fetal organ weights and on placental growth and structure. Embryos that had been exposed to either a normal or a high concentration of progesterone on days 1–3 in initial recipient ewes were transferred at random to final recipient ewes that had or had not been treated with progesterone on days 1–3. Embryos in an additional group of ewes were exposed to progesterone on days 1–3 with oviducts of the ewes ligated. An increase in fetal weight was observed in the final recipient group that had been treated with progesterone (P< 0.01) but not in the initial group treated with progesterone. Fetal weight was increased (P< 0.05) in the initial recipients treated with progesterone plus ligation. Placental weight did not differ between any of the treatments in either initial or final recipients, while placental volumes of chorionic membrane and maternal crypts were increased by progesterone, with and without ligation, in initial recipients (P< 0.05). The responses of fetal weight in final recipients were associated with increases in the weight and linear dimensions of specific fetal components (e.g. brain...

Infant-directed behaviour in the naturally paternal male dwarf hamster, Phodopus campbelli, is neither activationally nor organizationally regulated by activity at the progesterone receptor

THORPE, JOELLE
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 5600390 bytes; application/pdf
Português
Relevância na Pesquisa
37.01%
Phodopus campbelli is a naturally biparental dwarf hamster with males so paternal they will act as midwives during the birth of their litter. The hormonal regulation of parental behaviour has been well established in many species. However, to date, no causal mechanism for the extensive paternal behaviour displayed by male P. campbelli has been discovered. Recently, activity at the progesterone receptor has been shown to inhibit infant-directed behaviour in male mice. Therefore, the first study in this thesis was carried out to determine if antagonism of the progesterone receptor (PR) would enhance infant-directed care behaviour in naïve P. campbelli males. Despite detectable serum progesterone concentration in males, PR antagonism did not alter progesterone concentration, nor did it alter infant-directed behaviour in males with antagonized PR in adulthood. A slight increase in the latency to retrieve a pup seen in males with antagonized PR during adolescence suggests that there may be a developmental effect of PR activity on infant-directed behaviour in adulthood. Neonatal male rats express high levels of PR in brain regions important for parental behaviour. Since hormones can act very early in life to organize adult behaviour...

Effects of metformin treatment on luteal phase progesterone concentration in polycystic ovary syndrome

Meenakumari,K.J.; Agarwal,S.; Krishna,A.; Pandey,L.K.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2004 Português
Relevância na Pesquisa
37.03%
The causes of luteal phase progesterone deficiency in polycystic ovary syndrome (PCOS) are not known. To determine the possible involvement of hyperinsulinemia in luteal phase progesterone deficiency in women with PCOS, we examined the relationship between progesterone, luteinizing hormone (LH) and insulin during the luteal phase and studied the effect of metformin on luteal progesterone levels in PCOS. Patients with PCOS (19 women aged 18-35 years) were treated with metformin (500 mg three times daily) for 4 weeks prior to the test cycle and throughout the study period, and submitted to ovulation induction with clomiphene citrate. Blood samples were collected from control (N = 5, same age range as PCOS women) and PCOS women during the late follicular (one sample) and luteal (3 samples) phases and LH, insulin and progesterone concentrations were determined. Results were analyzed by one-way analysis of variance (ANOVA), Duncan's test and Karl Pearson's coefficient of correlation (r). The endocrine study showed low progesterone level (4.9 ng/ml) during luteal phase in the PCOS women as compared with control (21.6 ng/ml). A significant negative correlation was observed between insulin and progesterone (r = -0.60; P < 0.01) and between progesterone and LH (r = -0.56; P < 0.05) concentrations...

Therapeutic effects of progesterone in animal models of neurological disorders

de Nicola, Alejandro Federico; Coronel, Maria Florencia; Garay, Laura Ines; Gargiulo Monachelli, Gisella Mariana; Gonzalez Deniselle, Maria Claudia; Gonzalez, Susana Laura; Labombarda, Maria Florencia; Meyer, Maria; Guennoun, Rachida; Schumacher, Michael
Fonte: Bentham Science Publishers Publicador: Bentham Science Publishers
Tipo: info:eu-repo/semantics/article; info:ar-repo/semantics/artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Português
Relevância na Pesquisa
37.05%
Substantial evidence supports that progesterone exerts many functions in the central and peripheral nervous system unrelated to its classical role in reproduction. In this review we first discussed progesterone effects following binding to the classical intracellular progesterone receptors A and B and several forms of membrane progesterone receptors, the modulation of intracellular signalling cascades and the interaction of progesterone reduced metabolites with neurotransmitter receptors. We next described our results involving animal models of human neuropathologies to elucidate the protective roles of progesterone. We described: (a) the protective and promyelinating effects of progesterone in experimental spinal cord injury; (b) the progesterone protective effects exerted upon motoneurons in the degenerating spinal cord of Wobbler mouse model of amyotropic lateral sclerosis; (c) the protective and anti-inflammatory effects of progesterone in the murine experimental autoimmune encephalomyelitis model of multiple sclerosis and after lysolecithin demyelination; (d) the progesterone prevention of nociception and neuropathic pain which follow spinal cord injury; and (e) the protective effect of progesterone in experimental ischemic stroke. Whenever available...

Progesterone is essential for protecting against LPS-induced pregnancy loss. LIF as a potential mediator of the anti-inflammatory effect of progesterone

Aisemberg, Julieta; Vercelli, Claudia Alejandra; Bariani, Maria Victoria; Billi, Silvia Cristin; Wolfson, Manuel Luis; Franchi, Ana Maria
Fonte: Public Library Science Publicador: Public Library Science
Tipo: info:eu-repo/semantics/article; info:ar-repo/semantics/artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Português
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37.03%
Abstract Lipopolysaccharide (LPS) administration to mice on day 7 of gestation led to 100% embryonic resorption after 24 h. In this model, nitric oxide is fundamental for the resorption process. Progesterone may be responsible, at least in part, for a Th2 switch in the feto-maternal interface, inducing active immune tolerance against fetal antigens. Th2 cells promote the development of T cells, producing leukemia inhibitory factor (LIF), which seems to be important due to its immunomodulatory action during early pregnancy. Our aim was to evaluate the involvement of progesterone in the mechanism of LPS-induced embryonic resorption, and whether LIF can mediate hormonal action. Using in vivo and in vitro models, we provide evidence that circulating progesterone is an important component of the process by which infection causes embryonic resorption in mice. Also, LIF seems to be a mediator of the progesterone effect under inflammatory conditions. We found that serum progesterone fell to very low levels after 24 h of LPS exposure. Moreover, progesterone supplementation prevented embryonic resorption and LPS-induced increase of uterine nitric oxide levels in vivo. Results show that LPS diminished the expression of the nuclear progesterone receptor in the uterus after 6 and 12 h of treatment. We investigated the expression of LIF in uterine tissue from pregnant mice and found that progesterone up-regulates LIF mRNA expression in vitro. We observed that LIF was able to modulate the levels of nitric oxide induced by LPS in vitro...

Eficiência da mensuração de progesterona salivar para identificar a ovulação em cadelas; Efficiency of salivary progesterone measurement to identify the ovulation in bitches

Lopes, Patricia Rotta; Furtado, Priscila Viau; Oliveira, Claudio Alvarenga de
Fonte: Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia Publicador: Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf
Publicado em 22/02/2013 Português
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36.98%
Vários autores enfatizaram a importância do monitoramento do ciclo estral em cadelas e citaram exemplos de como realizar tal procedimento. O objetivo deste estudo foi avaliar a técnica de dosagem de progesterona salivar em cadelas para identificar a ovulação nesta espécie. Para composição do grupo experimental, foram utilizadas 13 cadelas, de diferentes raças (sem raça definida, Buldogue Inglês, Bernesse Mountain Dog) e diferentes idades (11 meses a 9 anos).Amostras de sangue e saliva foram colhidas simultaneamente em todos os animais, a partir dos primeiros sinais clínicos de proestro. Amostras salivares foram obtidas com o uso de dispositivo comercial específico (Salivette®). Este método foi eficaz, visto ter tornado possível obter volume suficiente para dosagem de progesterona na grande maioria das amostras(100 μL para dosagens em duplicata). As concentrações de progesterona no soro foram determinadas pela técnica de radioimunoensaio e na saliva por enzimaimunoensaio, ambas com kits comerciais. Observou-se uma relação linear crescente e positiva entre a progesterona sérica e salivar (r=0,704; p<0,0001) em cadelas. Uma das cadelas apresentou ciclo anovulatório, no qual, durante 13 dias, as concentrações séricas de progesterona sérica se mantiveram entre 1...

Plasma concentration of progesterone and 17ß-estradiol of black-rumped agouti (Dasyprocta prymnolopha) during the estrous cycle

Guimarães,Diva Anelie; Ramos,Rosemar Luz; Ohashi,Otávio Mitio; Garcia,Gary Wayne; Gomes Vale,William
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2011 Português
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Plasma concentration of progesterone and 17β-estradiol of black-rumped agouti (Dasyprocta prymnolopha) during the estrous cycle. The agouti is a game animal that have been raised in captivity for conservation and sustainability purposes. However, the management of wild animals in an intensive breeding system requires an assertive knowledge of its reproductive parameters, one of the most important features for production improvement. Besides, little information is available regarding changes in reproductive hormone profiles in agouti. The objective of this study was to evaluate the hormonal profile of progesterone and 17β-estradiol during the estrous cycle of the agouti (Dasyprocta prymnolopha). The hormones were analyzed by radioimmunoassay. Blood samples were collected without sedation twice a week. The concentrations of progesterone were as follows: proestrus 0.78+0.39ng/ml, estrus 2.83+2.34ng/ml, metestrus 1.49+1.24ng/ml, diestrus 3.71+1.48ng/ml. In the estrous phase, an increase in the progesterone level was observed during a period of 24h. The average 17 β-estradiol levels were as follows: proestrus 2 030.98+961.00pg/ml, estrus 1 910.56+650.54pg/ml, metestrus 1 724.83+767.28pg/ml, diestrus 1 939.94+725.29pg/ml. The current results suggest that the progesterone plasma concentration during the estrous cycle in the agouti has a similar increasing...