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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
311

Avaliação da influência da expressão da indoleamina 2,3-dioxigenase no ciclo celular de células placentárias e embrionárias murinas e de ratas em cultivo celular, frente à ação de hormônios e citocinas / Evaluation of the influence of the expression of indoleamine 2,3-dioxygenase on the cell cycle of murine and rat embryonic cells and placental cells in culture supplemented with hormones and cytokines

Santos, Graziela Menck Ferreira 19 December 2012 (has links)
A indoleamina 2,3-dioxigenase (IDO) desempenha um papel importante na tolerância materno-fetal devido á sua ação de catabolizar o triptofano e, consequentemente, impedir a proliferação de linfócitos T, que necessitam desse aminoácido para se manter. Hormônios da reprodução também participam do processo de sobrevivência do feto alogênico, como a progesterona que bloqueia o estímulo mitogênico da proliferação de células T, modula a produção de anticorpos, favorece a produção de IL-10, etc. e o estradiol, que pode modular o perfil imune Th1 ou Th2 na gestação, dependendo de sua concentração. Contudo, a existência ou não de correlação da ação da IDO com esses hormônios ou vice-versa ainda encontra-se pouco evidenciada. Desta forma este trabalho verificou a influência da expressão da IDO e às ações de hormônios da reprodução e citocinas no ciclo celular de células oriundas de fetos e placenta de gestação a termo de fêmeas de ratas e camundongos em cultivo. Este estudo foi realizado em complementação a um trabalho anterior, no qual foi realizada uma avaliação da expressão da IDO por citometria de fluxo em células uterinas, de placentas e de embriões de ratas e camundongos fêmeas prenhes e não prenhes que foram mantidas em cultivo e suplementadas com estradiol, progesterona, interferon γ, triptofano e 1-metil-DL- triptofano. A avaliação das fases do ciclo celular foi realizada pela citometria de fluxo. De acordo com os resultados, em relação ao efeito dos tratamentos no comportamento das células no ciclo celular, podemos observar que, em ratas prenhes e não prenhes, ao adicionar estradiol, houve maior predominância das células em fase G1 nos períodos de 4 e 24 horas, bem como no grupo de camundongos fêmeas prenhes. Algumas células uterinas de ratas não prenhes tratadas com estradiol, assim como as tratadas com progesterona e interferon γ progrediram no ciclo para fase de síntese nos tempos de 24 e 48 horas. Com a adição de triptofano podemos notar nos grupos de ratas não prenhes, camundongos fêmeas prenhes e não prenhes, um aumento da quantidade de células na fase G1 nos três períodos analisados. No grupo de ratas prenhes foi observado uma predominância celular em fase G1 nos tempos de 4 e 24 horas, sendo que em 48 horas, as células sofreram fragmentação de DNA. As células que foram suplementadas com 1- metil DL - triptofano + triptofano mantiveram o mesmo comportamento no ciclo celular , se mantendo em fase G1 nos tempos de 4, 24 e 48 horas grupos prenhes e não prenhes de ratas e nos tempos de 4 e 24 horas nos grupos de camundongos fêmeas prenhes e não prenhes, estando com seu DNA fragmentado e em fase de síntese, respectivamente, no tempo de 48 horas. A suplementação dos diversos fatores aos cultivos celulares permitiu observar alterações na dinâmica do ciclo celular, representada principalmente por um aumento de células em fase G1 nos grupos de células placentárias e embrionárias que receberam progesterona, estradiol, interferon γ e triptofano e apresentaram um significativo aumento da expressão de IDO, e que permite inferir que provavelmente a síntese de RNAm esteja correlacionada à produção da IDO. / The indoleamine 2,3-dioxygenase (IDO) plays an important role in maternal-fetal tolerance due to its capacity to catabolize tryptophan and thereby preventing the proliferation of T lymphocytes, necessary for their maintenance. Reproductive hormones are also involved in the process of survival of semi-allogeneic fetus, as progesterone that blocks mitogenic stimulation of T cell proliferation, modulates antibodies production, promotes production of IL-10, etc. and estradiol, that can modulate the Th1 or Th2 immune profile during pregnancy, depending on its concentration. However, there is very few evidences regarding a possible correlation between IDO expression and these hormones; thus this study examined the influence of the expression of IDO and the actions of reproductive hormones and cytokines in the cell cycle of cells derived from fetuses and placenta at term gestation of female rats and mice in culture. This study was conducted as a complement to an earlier work, in which an evaluation was made of the IDO expression by flow cytometry in uterine cells, placentas and embryos of pregnant rats and mice and non-pregnant females that were maintained in culture and supplemented with estradiol, progesterone, interferon γ, tryptophan and 1-methyl-DLtryptophan. The cell cycle evaluation was conducted by flow cytometry. According to the results, regarding the effect of treatments on the behavior of the cells in the cell cycle, it was observed that in pregnant and non-pregnant rats after the addition of estradiol, there is a greater predominance of cells in G1 phase at periods of 4 and 24 hours, that also was noted in the group of pregnant female mice. Uterine cells from non-pregnant female rats treated with estradiol and progesterone as well as treated with interferon γ progressed to the phase of synthesis on the cycle, at 24 and 48 hours. With the addition of tryptophanin the groups of non-pregnant rats, pregnant and non-pregnant mice , an increased amount of cells in the G1 phase were observed in the three periods analyzed. In the group of pregnant rats a predominance of cells in the G1 phase was observed in periods of 4 and 24 hours, and 48 hours, where the cells undergone DNA fragmentation. In pregnant and non-pregnant rats the cells supplemented with 1 - methyl - DL - tryptophan + tryptophan remained at G1 phase in periods of 4, 24 and 48 hours and 4 and 24 hours for cells from pregnant and non-pregnant mice , that show ragmented DNA followed by synthesis at 48 hours period. Supplementation of the various factors to cell cultures allowed to observe dynamic changes in the cell cycle, represented primarily by an increase of cells in G1 phase in groups of embryonic and placental cells that received progesterone, estradiol, interferon γ and tryptophan and showed a significant increase in the expression of IDO, that allows us to infer that the mRNA synthesis is probably correlated to the production of IDO.
312

Resposta superovulatória na primeira onda de crescimento folicular em doadoras Nelore (Bos indicus) / Superovulatory response during the first follicular wave in Nelore (Bos indicus) donors

Nasser, Luiz Fernando Tonissi 31 January 2006 (has links)
Três experimentos foram realizados para testar a hipótese de que a resposta superestimulatória de doadoras Nelore (Bos indicus) com tratamentos iniciados próximo à ovulação durante a primeira onda de crescimento folicular seria maior ou comparável àquela decorrente de tratamentos convencionais. Os animais foram aleatoriamente alocados em três grupos. As doadoras dos Grupos 1 - Onda 1 s/P4 e 2 - Onda 1 c/P4 foram superestimuladas na primeira onda de crescimento folicular, e as do Grupo 3 - SincBE+P4/P4 quatro dias após a sincronização da emergência folicular com estradiol e progesterona. Os animais receberam dispositivo intravaginal de Progesterona (CIDR) associado a 50mg de Progesterona e 2,5mg de Benzoato de Estradiol (IM) no Dia 0. Os animais dos Grupos 1 e 2 receberam PGF2&alpha; no Dia 5 e 12,5mg Armour de LH (Lutropin) 24 horas após a remoção do CIDR (Dia 9), e no Dia 11 iniciou-se o tratamento superovulatório. As doadoras do Grupo 2 receberam um novo CIDR juntamente com a primeira dose de FSH (Dia 11). Todos os animais foram superestimulados com 133mg NIH-FSH-P1 de Folltropin diluídos em 10ml, em duas aplicações diárias de 1ml, por cinco dias. No último dia de tratamento, junto com o FSH foram aplicadas doses luteolíticas de PGF2&alpha; nos Grupos 2 e 3 o CIDR foi removido na ultima aplicação. Todas as doadoras receberam 25mg de LH 24 horas após a ultima dose de FSH e foram inseminadas 12 e 24 horas após o LH. Os embriões foram coletados e avaliados pelo mesmo veterinário sete dias após a inseminação. No primeiro experimento, as quantidades de embriões transferíveis não foi significativamente diferente entre os grupos 2 e 3 (8,0 ± 1,8 x 6,6 ± 2,0), e ambas foram maiores que as do 1 (0,2 ± 0,2; P<0,05). Como não houve diferença entre os Grupos 2 e 3 nos parâmetros analisados, o Grupo 3 foi excluído dos outros dois experimentos. No segundo experimento, as doadoras receberam os mesmos tratamentos dos Grupos 1 e 2, mas foram abatidas 12 horas após receberem 25mg de LH (Dia 16) e tiveram seus ovários removidos e levados para o laboratório, para classificação. Os oócitos foram aspirados e avaliados quanto à maturação pela expansão do COC. Os animais que não receberam dispositivo de P4 durante o tratamento superovulatório apresentaram maior número de oócitos não maturados (6,4 ± 2,7 x 1,2 ± 0,9; P< 0,05). O terceiro experimento foi semelhante ao segundo, com a diferença de que os animais foram inseminados 12 horas após o tratamento com 25mg de LH, e tiveram as estruturas coletadas 7 dias após a IA. Os resultados desse experimento confirmaram os do primeiro, no qual animais sem suplementação exógena de P4 durante o tratamento superovulatório apresentaram menor número de embriões transferíveis que o grupo com P4 (0,0 ± 0,0 x 3,9 ± 1,1; P<0,05). Os resultados obtidos retificam a hipótese, demonstrando que a superovulação durante a primeira onda de crescimento folicular em novilhas Nelore é eficiente somente com suplementação exógena de P4 / Three experiments were design to test the hypothesis that superovulatory (SPO) response of Nelore (Bos indicus) donors to treatments administered during the first follicular wave, initiated at the expected time of ovulation, will elicited a higher or a comparable response to traditional protocols. In the first experiment, cows were randomly allocated into 1 of 3 treatment groups. Cows in Group Wave 1 without P4 e Group Wave 1 with P4 were superstimulated during the first follicular wave and cows in the Control Group were superstimulated after synchronized follicular wave emergence using estradiol and progesterone. All cows received a CIDR device and an injection of 50mg of P4 and 2.5mg EB on Day 0. Cows in Groups Wave 1 with P4 and Wave 1 without P4 were also treated with PGF2&alpha; on Day 5 and 12,5mg Armour of pLH (Lutropin) 24 h after CIDR removal (Day 9), to synchronize ovulation. The SPO treatments were initiated on Day 11; donor cows in Group Wave 1 with P4 also received a new CIDR device at the time of the first FSH injection. All donors in three groups were superstimulated with a total dose of 133mg NIH-FSH-P1 of Folltropin-V, divided into twice daily injections of the same dosage (13,3mg diluted in 1ml) over 5 days. On the last day of FSH treatment, all animals received PGF2&alpha; after each FSH injection and cows in Group Wave 1 with P4 and Control Group had their CIDR removed at the time of the last FSH injection. All cows received 25 mg of pLH 24h after the last FSH treatment and were AI 12 and 24h later. Ova/embryo collection and evaluation was done 7d after, aIl by the same veterinarian. Results indicate that there was no difference in the numbers of transferable embryos in CIDR treated donor cows when SPO treatments were initiated at the time of emergence of either the first follicular wave Group Wave 1 with P4 (8.0 ± 1.8) or following synchronization of follicular wave emergence with BE + P4, control Group (6.6 ± 2.0), but both were greater than when SPO treatments were initiated at the first follicular wave without the use of a CIDR device, Wave 1 without P4 (0.2 ± 0.2; P<0,05). Since there were no differences between Groups Wave 1 with P4 and control on all the end points, this group was dropped from the others experiments. A second experiment was performed in order to evaluate the quality of oocyte recovered after animals were treated under the same protocol of Groups Wave 1. The SPO treatments were the same described previously, however 12h after the injection of 25mg of pLH animals were slaughtered and their ovaries were taken to an IVF lab. Follicles were aspirated and the oocyte was evaluated and those with an expanded COC were considered mature. Animals in Group Wave 1 without P4 showed a greater (P<0,05) number of immature oocyte (6.4 ± 2.7) than Group Wave 1 with P4 (1.2 ± 0.9). The third experiment was performed to confirm the results of the first experiment. The treatments were similar as the second experiment, however, animals were AI 12 and 24h after the 25mg of pLH and had ova/embryos collection and evaluation 7 d after by the same veterinarian. Results of this experiment confirmed the first experiment presenting a greater (P<0,05) number of transferable embryos in Group Wave 1 with P4 (3.9 ± 1,1) when compared to Group Wave 1 without P4 (0.0 ± 0.0). The results did not support the hypothesis, showing that exogenous P4 is necessary in order to superovulate Nelore during the first follicular wave
313

Breast Cancer Risk Factors and Associations with Breast Cancer Tumor Characteristics in High Risk Populations

Work, Meghan E. January 2018 (has links)
Background: Estrogen receptor (ER)- and progesterone receptor (PR)-negative (ER-PR-) breast cancer is associated with higher grade and poorer prognosis compared with other breast cancer subtypes. High parity, coupled with lack of breastfeeding, has been associated with an increased risk of ER-PR- cancer. The mechanism of this etiology is unclear, and may be obfuscated by ER and PR correlation with each other as well as other prognostic tumor characteristics. Methods: Using population-based and clinic-based ascertained cases and controls from the Breast Cancer Family Registry, I examined reproductive risk factors, including parity, breastfeeding, and oral contraceptive (OC) use, in relation to ER and PR status, using polytomous logistic regression (for the population-based data) and the method of generalized estimating equations (GEE) (for the clinic-based data) as well as the pseudo-conditional likelihood approach, which accounts for correlated outcome variables. Results: High parity (≥ 3 live births) combined with lack of breastfeeding, was positively associated with ER-PR- tumors (odds ratio [OR]=1.57, 95% confidence interval [CI] 1.10-2.24, population-based cases vs. controls) relative to nulliparity. There was no association with ER-PR- tumors and parity in women who breastfed (OR=0.93, 95%CI 0.71-1.22) relative to nulliparous women. Associations with ER-PR- cancer were higher across all races/ethnicities among women who did not breastfeed compared with women who did. Population-based and clinic-based data were generally in agreement (OR=2.07, 95% CI 1.09-3.91, clinic-based cases vs. controls, relative to nulliparity). When adjusted for the correlation of PR-status and grade, to ER-status, the association between high parity +lack of breastfeeding and ER- status, was maintained. OC use before year 1975 was associated with an increased risk of ER-PR- tumors (OR=1.32, 95% CI 1.04-1.67, population-based data, cases vs. controls) relative to never use of OCs. For women who began OC use in 1975 or later there was no increased risk. Analysis of OC use in clinic-based data agreed with the findings of the population-based data. Conclusions: My findings support that there are modifiable factors for ER-PR- breast cancer, and that breastfeeding in particular may mitigate the increased risk of ER-PR-cancers seen from multiparity. The mechanism of both risk and risk mitigation may operate primarily through the estrogen, rather than progesterone, pathway.
314

Efeitos do tramadol no modelo de dor induzida por obstrução intestinal em eqüinos

Lopes, Maristela de Cassia Seudo [UNESP] 22 February 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-22Bitstream added on 2014-06-13T20:09:23Z : No. of bitstreams: 1 lopes_mcs_me_jabo.pdf: 1425980 bytes, checksum: ec77cfbfaaacc7792256be3564bbc255 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Avaliaram-se os efeitos clínico e comportamental da injeção intravenosa do tramadol no controle da dor induzida experimentalmente, por obstrução intestinal extraluminal, com dreno de Pen Rose. Foram utilizados 24 cavalos distribuídos em quatro grupos: controle (GC, n=6); obstrução duodenal (GD, n=6); obstrução de íleo (GI, n=6) e obstrução de flexura pélvica (GFP, n=6). Após medicação pré-anestésica com a associação de acepromazina (0,025 mg.kg-1 IV), xilazina (0,5 mg.kg-1 IV) e meperidina (4 mg.kg-1 IM), o tramadol foi administrado nas doses de 1,0 mg.kg-1 e 1,5 mg.kg-1, por via intravenosa (IV), imediatamente após a obstrução intestinal, em três cavalos de cada grupo. Avaliaram-se as freqüências cardíaca (FC) e respiratória (f), temperatura retal (TºC), tempo de preenchimento capilar (TPC), motilidade intestinal, comportamento relacionado à dor (olhar para o flanco, cavar, deitar e rolar) hemograma e hemogasometria venosa, nos intervalos: M0 (basal) a cada 0,5 hora de M1 a M6 , na fase de obstrução, e até três horas após a reversão do processo obstrutivo (M7 a M12). Os resultados demonstraram que não houve diferença significativa entres as doses utilizadas dentro de cada grupo, assim como entre os grupos. Houve aumento da FC em M11 no GD e em M12 no GFP. Os sinais de dor abdominal e atonia intestinal iniciaram-se em M5 no GFP e em M6 no GI. Nos animais do GD, os sinais de desconforto não progrediram. No leucograma foi observado um quadro característico de estresse e na hemogasometria os animais do GD tendenciaram à alcalose metabólica com compensação respiratória. Clinicamente, observou-se que a dose de 1,5 mg.kg-1 de tramadol proporcionou melhor conforto para os animais, porem sem significado estatístico, quando comparado coma dose de 1,0 mg.kg-1... / The clinical and behavioral effects of the intravenous injection of tramadol were evaluated during the control of pain induced experimentally due to intestinal extraluminal obstruction using “Pen Rose” drain. A total of 24 horses were used and distributed in four groups: control (GC, n=6); duodenal obstruction (GD, n=6); ileum obstruction (GI, n=6) and pelvic flexure obstruction (GFP, n=6). After administration of pre-anesthetic medications using association of acepromazine (0.025 mg.kg-1 IV), xylazine (0.5 mg.kg-1 IV) and meperidine (4 mg.kg-1 IM), tramadol was administered at doses of 1.0 mg.kg-1 and 1.5 mg.kg-1 intravenously (IV), immediately after the intestinal obstruction in three horses of each group. Evaluations were performed, including heart rate (HR), respiratory rate (RR), rectal temperature (RT), capillary refill time (CRT), gut motility, pain-related behaviour (look for the sidewall, dig down and roll) and blood gases from venous blood at the time: M0 (baseline) and every 0.5 hours from M1 to M6, during obstruction process and also until three hours after the obstructive process be reverted (M7 to M12). The results showed no significant difference among the doses used in the same group as among groups. There was an increase in HR in the GD M11 and M12 of GFP. Signs of abdominal pain and intestinal atony began at M5 in GFP and at M6 in GI. In animals from GD, the discomfort signs did not showed progress. On the leucogram was observed a typical stress and on the blood gas analysis the animals from GD showed a tendency to metabolic alkalosis with respiratory compensation. Clinically, was observed that the dose of 1.5 mg.kg-1 of tramadol provided better comfort to the animals, but there was not statistical significance, compared with the dose 1.0 mg.kg-1... (Complete abstract click electronic access below)
315

Non-genomic and genomic effects of estrogen and progesterone on mammalian arteries.

January 2001 (has links)
Chan Hoi Yun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 131-144). / Abstracts in English and Chinese. / DECLARATION --- p.i / ACKNOWLEDGMENTS --- p.ii / ABBREVIATIONS --- p.iii / ABSTRACT IN ENGLISH --- p.v / ABSTRACT IN CHINESE --- p.viii / CONTENTS --- p.xi / Chapter Chapter 1 --- Introduction / Chapter 1.1. --- Steroid Hormones --- p.1 / Chapter 1.1.1. --- Synthesis of estrogens and progesterone --- p.1 / Chapter 1.2. --- Cellular Mechanisms of Female Steroid Hormones --- p.5 / Chapter 1.2.1. --- Genomic actions of female steroid hormones --- p.5 / Chapter 1.2.2. --- Non-genomic actions of female steroid hormones --- p.7 / Chapter 1.2.3. --- Estrogen antagonists --- p.7 / Chapter 1.2.3.1. --- Classification of estrogen antagonists --- p.7 / Chapter 1.2.3.2. --- Mechanisms of estrogen antagonists --- p.9 / Chapter 1.3. --- Chronic (genomic) Effects of 17β-Estradiol and Progesterone --- p.10 / Chapter 1.3.1. --- Effects of lipid metabolism --- p.10 / Chapter 1.3.2. --- Effects on cell proliferation --- p.11 / Chapter 1.3.3. --- Effects on endothelial cells --- p.12 / Chapter 1.4. --- Acute Effects of 17β-Estradiol and Progesterone --- p.13 / Chapter 1.4.1. --- Role of endothelium in 17β-estradiol or progesterone Relaxation --- p.13 / Chapter 1.4.2. --- Involvement of plasma membrane estrogen receptors --- p.14 / Chapter 1.4.3. --- Role of Ca2+ and K+ channel in estrogen relaxation --- p.14 / Chapter 1.4.4. --- Interaction with vasoconstrictors --- p.15 / Chapter 1.4.5. --- Interaction with endothelium-dependent dilators --- p.16 / Chapter 1.4.6. --- Interaction with adrenergic response --- p.17 / Chapter 1.5. --- Clinical Studies --- p.19 / Chapter 1.6. --- Therapeutic Values of Estrogen and Progesterone --- p.20 / Chapter 1.7. --- Objectives of the Present Study --- p.22 / Chapter Chapter 2 --- Method and Materials / Chapter 2.1. --- Tissue Preparation --- p.25 / Chapter 2.1.1. --- "Preparation of the rat aorta, mesenteric artery and carotid Artery" --- p.25 / Chapter 2.1.2. --- Removal of the functional endothelium --- p.26 / Chapter 2.2. --- Organ Bath Set-up --- p.26 / Chapter 2.3. --- Force Measurement --- p.28 / Chapter 2.3.1. --- Vascular action of 17β-estradiol and progesterone --- p.29 / Chapter 2.3.1.1. --- Role of endothelium/nitric oxide in 17β-estradiol- or progesterone-induced relaxation --- p.29 / Chapter 2.3.1.2. --- Role of inducible nitric oxide in progesterone-induced relaxation --- p.30 / Chapter 2.3.1.3. --- Effect of estrogen receptor inhibitor on 17β-estradiol- induced relaxation --- p.30 / Chapter 2.3.1.4. --- Interaction between progesterone and 17β-estradiol --- p.31 / Chapter 2.3.1.5. --- Effect of 17β-estradiol on protein kinase C-mediated contraction --- p.31 / Chapter 2.3.1.6. --- Synergistic interaction between β-adrenoceptor agonists and 17β-estradiol --- p.32 / Chapter 2.4. --- Porcine Coronary Artery Experiments --- p.33 / Chapter 2.4.1. --- Vessel preparation --- p.33 / Chapter 2.4.2. --- Force measurement --- p.33 / Chapter 2.4.3. --- Experimental protocol --- p.34 / Chapter 2.4.3.1. --- Effect of physiological level of 17β-estradiol on β- adrenoceptor agonist-induced relaxation --- p.34 / Chapter 2.4.3.2. --- Effect of physiological level of 17β-estradiol on phosphodiesterase inhibitor-induced relaxation --- p.34 / Chapter 2.5. --- Ovariectomy --- p.35 / Chapter 2.5.1. --- Method of ovariectomy --- p.35 / Chapter 2.5.2. --- Preparation of blood vessels --- p.36 / Chapter 2.5.3. --- Experimental protocols --- p.38 / Chapter 2.5.3.1. --- Effect of ovariectomy on contractility of rat carotid arteries --- p.38 / Chapter 2.5.3.2. --- Effect of ovariectomy on relaxation of rat carotid arteries --- p.38 / Chapter 2.6. --- Chemicals and Solutions --- p.39 / Chapter 2.7. --- Statistical Analysis --- p.42 / Chapter Chapter 3 --- Results / Chapter 3.1. --- Role of Endothelium/Nitric Oxide in 17β-Estradiol- and Progesterone-induced Relaxations --- p.43 / Chapter 3.1.1. --- Relaxant response of 17β-estradiol --- p.43 / Chapter 3.1.2. --- Effects of inhibitors of nitric oxide activity on 17β- estradiol-induced relaxation --- p.46 / Chapter 3.1.3. --- Relaxant response of progesterone --- p.46 / Chapter 3.1.4. --- Effects of inhibitors of nitric oxide activity on progesterone-induced relaxation --- p.50 / Chapter 3.2. --- Effect of Estrogen Receptor Inhibitor on 17β-Estradiol- induced Relaxation --- p.56 / Chapter 3.3. --- Interaction between Progesterone and 17β-Estradiol --- p.56 / Chapter 3.4. --- Effect of Female Sex Steroid Hormones on Protein Kinase C-mediated Contraction --- p.59 / Chapter 3.4.1. --- Effect of 17β-estradiol on phorbol ester-induced contraction --- p.59 / Chapter 3.4.2. --- Effect of progesterone on phorbol ester-induced contraction --- p.59 / Chapter 3.5. --- Effects of β-adrenoceptor Agonists on 17β-Estradiol- induced Relaxations --- p.62 / Chapter 3.5.1. --- Effect of isoproterenol on 17β-estradiol-induced relaxation --- p.62 / Chapter 3.5.2. --- Role of endothelium/nitric oxide on the isoproterenol potentiation of 17β-estradiol-induced relaxation --- p.63 / Chapter 3.5.3. --- Role of cyclic AMP on isoproterenol-enhancement of 17β- estradiol-induced relaxation --- p.69 / Chapter 3.5.4. --- Effects of β-adrenoceptor antagonists --- p.69 / Chapter 3.6. --- Effects of Physiological Concentration of 17β-EstradioI onβ-adrenoceptor Agonists-induced Relaxationsin Porcine Coronary Artery --- p.77 / Chapter 3.6.1. --- Effect of 17β-estradiol on isoproterenol-induced relaxations --- p.77 / Chapter 3.6.2. --- Effect of 17β-estradiol on fenoterol-induced relaxations --- p.11 / Chapter 3.6.3. --- Effect of 17β-estradiol on dobutamine-induced relaxations --- p.81 / Chapter 3.6.4. --- Effect of 17β-estradiol on IBMX-induced relaxation --- p.86 / Chapter 3.7. --- Effect of Ovariectomy on the Vascualr Reactivity --- p.88 / Chapter 3.7.1. --- Effect of ovariectomy on the contractile activity of rat carotid artery --- p.88 / Chapter 3.7.1.1. --- Effect of ovariectomy on phenylephrine-induced contraction --- p.88 / Chapter 3.7.1.2. --- Effect of ovariectomy on U46619-induced contraction --- p.96 / Chapter 3.7.1.3. --- Effect of ovariectomy on high K+- induced contraction --- p.102 / Chapter 3.7.1.4. --- Effect of ovariectomy on acetylcholine-induced relaxation --- p.106 / Chapter Chapter 4 --- Discussions / Chapter 4.1. --- Role of Endothelium/Nitric oxide in 17β-Estradiol- and Progesterone-induced Relaxations --- p.110 / Chapter 4.2. --- Effect of Estrogen Receptor Inhibitor on 17β-Estradiol- induced Relaxation --- p.113 / Chapter 4.3. --- Interaction between Progesterone and 17β-Estradiol --- p.114 / Chapter 4.4. --- Effects of Female Sex Steroid Hormones on Protein Kinase C-mediated Contraction --- p.115 / Chapter 4.5. --- Effects of β-Adrenoceptor Agonists on 17β-Estradiol- induced Relaxations --- p.116 / Chapter 4.6. --- Effects of 17β-Estradiol on β-Adrenoceptor Agonists- induced Relaxations in Porcine Coronary Artery --- p.121 / Chapter 4.7. --- Effect of Ovariectomy on the Vascular Reactivity --- p.125 / Chapter 4.8. --- Conclusions --- p.129 / References --- p.131 / Publications --- p.145
316

A influência de contraceptivos orais combinados na condição periodontal / The influence of combined oral contraceptives on the periodontal condition

Domingues, Roberta Santos 20 March 2009 (has links)
Durante as diferentes fases da vida, ocorrem alterações nos níveis dos hormônios sexuais no organismo. Estes períodos estão diretamente associados com episódios de inflamação periodontal exacerbada. Por isso, a relação entre níveis alterados dos hormônios sexuais e variações no grau de inflamação gengival tem sido estudada. Como os contraceptivos orais alteram artificialmente os níveis dos hormônios sexuais, o objetivo deste estudo é avaliar a influência de contraceptivos orais combinados atuais na condição periodontal de 25 mulheres entre 19 e 35 anos de idade que fazem uso deste medicamento pelo período mínimo de 12 meses em comparação ao grupo controle de 25 mulheres, dentro do mesmo limite de idade, que não fazem uso de contraceptivos orais. As pacientes foram avaliadas por examinador único, previamente treinado, cego em relação ao uso do contraceptivo, quanto às medidas de profundidade de sondagem, nível de inserção clínica, índice de sangramento do sulco e índice de placa. Os dados obtidos foram analisados estatisticamente segundo o teste t não pareado, teste de correlação de Pearson e teste de correlação de Spearman. Os resultados obtidos indicaram que mulheres que fazem uso de contraceptivos orais há mais de um ano apresentam maior profundidade de sondagem (2,228±0,011 x 2,154±0,012; p<0.0001), perda de inserção (0,435±0,01 x 0,412±0,01; p=0.11) e índice de sangramento do sulco (0,229±0,006 x 0,148±0,005, p<0.0001) do que o grupo controle, embora o índice de placa tenha sido menor no grupo teste do que no controle (0,206±0,007 x 0,303±0,008; p<0.0001). Não houve correlação entre o tempo de uso do medicamento, idade e nenhum dos parâmetros periodontais clínicos. Esses achados sugerem que o uso de contraceptivos orais combinados disponíveis atualmente no mercado pode influenciar a condição periodontal das pacientes, independentemente da quantidade de placa presente e do tempo de uso dos contraceptivos, resultando em maior inflamação da gengiva marginal. / During the different life phases, sexual hormones levels can be altered. These periods are directly associated to episodes of increased periodontal inflammation. Because of this, the relation between altered levels of sexual hormones and degree of gingival inflammation has been studied. As oral contraceptives artificially modify sexual hormones levels, the aim of this study is to evaluate the effects of this drug in the periodontal condition of 25 women aged 19-35 years old that have been taking oral contraceptives for at least one year compared to a control group composed of 25 patients at the same age range that do not report the use of oral contraceptives. Patients were evaluated by a previously trained, single blinded examiner according to pocket probing depth, clinical attachment level, bleeding on probing and plaque index. Data was statistically evaluated by unpaired t test, Pearsons correlation test and Spearmans correlation test. The results obtained indicated that women taking oral contraceptives for at least one year show increased probing pocket depth (2.228±0.011 x 2.154±0.012; p<0.0001), attachment loss (0.435±0.01 x 0.412±0.01; p=0.11) and bleeding on probing (0.229±0.006 x 0.148±0.005, p<0.0001) than the control, although plaque index was slightly inferior in test than in control group (0.206±0.007 x 0.303±0.008; p<0.0001). No correlation between the duration of oral contraceptives intake, age and periodontal parameters was observed. These findings suggest that the use of currently available combined oral contraceptives can influence the periodontal condition of the patients, independent from plaque accumulation and the duration of use of the medication, resulting in increased gingival inflammation.
317

"Pesquisa dos receptores de estrógeno (RE) e do receptor da progesterona (RP) in vivo e verificação da influência destes hormônios in vitro em duas linhagens de adenomas pelomórficos" / "In vivo study of estrogen (RE) and progesterone (RP) receptors and verification of the in vitro effect of these hormones in two pleomorphic adenoma cell lines"

Carvalhosa, Artur Aburad de 10 December 2001 (has links)
RESUMO A similaridade entre o tecido da mama e o da glândula salivar está bem estabelecida. A porção das estruturas acinares e ductais destes órgãos são basicamente semelhantes. Estes aspectos, associados ao fato de que uma coexistência de carcinomas da mama e de glândula salivar, têm sido relatados em uma incidência maior do que a esperada. Guiaram estudos tentando determinar a importância dos receptores de estrógeno e progesterona em adenomas pleomórficos (AP). A neoplasia é mais freqüente nas glândulas salivares e exibe uma predileção para o sexo feminino. Recentemente a presença do receptor de estrógeno (RE) e do receptor de progesterona (RP) tem sido investigada no AP, entre outras neoplasias de glândula salivar, questionando-se a possibilidade da existência da dependência hormonal. A expressão dos receptores hormonais nos carcinomas de mama é importante para determinar o prognóstico e a probabilidade de responder à manipulação hormonal. Neoplasias que apresentam positividade para ambos os receptores, estrógeno e progesterona, exibem maior probabilidade de resposta à terapia anti-estrogênica do que as neoplasias que são negativas para estes receptores. Baseando-se na literatura científica pertinente, o presente trabalho se propõe a investigar a presença da proteína RE e da proteína RP em APs humanos, relacionando-os com a proliferação de linhagens celulares sob a influência destes hormônios. A técnica utilizada foi a imuno-histoquímica para a pesquisa dos RE e RP em 10 APs emblocados em parafina pertencentes ao arquivo do Serviço de Patologia Cirúrgica da FOUSP, e de duas linhagens de APs estabelecidas no mesmo serviço: uma derivada de um paciente do sexo masculino e a outra de um paciente do sexo feminino. No meio de cultivo onde subculturas destas células proliferavam foram diluídos 17-b-estradiol e progesterona. Através de contagens destas células em períodos pré-determinados (24 horas, 48 horas e 72 horas), pretendeu-se verificar a influência dos respectivos hormônios na multiplicação celular. Como controle positivo utilizou-se uma linhagem denominada T-47D, que foi largamente estudada na literatura. A T-47D é derivada de um carcinoma metastático de mama, reconhecidamente hormônio dependente. E como controle negativo, utilizou-se de uma linhagem de carcinoma epidermóide, denominada HN30. Encontrou-se positividade para o RE em 7 de 10 APs estudados (4 em homens e 3 em mulheres) e positividade para o RP em 8 Aps estudados (4 em mulheres e 4 em homens). Pela análise estatística, constatou-se que existe uma diferença significativa no índice proliferativo entre o controle e as células submetidas à ação do 17-b-estradiol e da progesterona. Para a linhagem derivada do paciente do sexo masculino houve diferença entre o controle e as células expostas ao 17-b-estradiol e a progesterona somente nas últimas 72 horas. Para a linhagem derivada do sexo feminino constatou-se uma diferença significativa entre o controle e as células sob a influência da progesterona, a partir de 48 horas de proliferação celular. A diferença significativa entre o controle e as células sob a ação do 17-b-estradiol ocorreu somente a partir das 72 horas, sugerindo que o AP poderia ser uma neoplasia influenciada pela ação hormonal. / SUMARY It is well established the similarity between mammary and salivary glands especially between the acinic and ductile structures. These aspects, associated to the fact of coexistence of breast carcinomas and of salivary gland tumors been described, leaded studies in attempt to determine the importance of the ERs and Pr in pleomorphic adenomas (PA), the most frequent salivary gland tumor and with predilection for the females. Lately, the presence of ERs and of the PRs has been investigated in PA and other salivary gland tumors pointing out their hormonal dependency. The expression of hormone receptors in breast carcinomas is crucial to determine a presence for both receptors. These tumors exhibit better response to anti-estrogenic therapy than the negative ones. Basing on the pertinent scientific literature, the present study proposes to investigate the presence of the RE and of the RP in humans PA and connecting them with cellular proliferation in vitro, under the influence of these hormones. Immunohistochemistry technique was used for the detection of RE and RP in paraffin embedded 10 PAs from the files of the Department of Oral Pathology, School of Dentistry, University of São Paulo, and two PA cell lines one from a male patient and other female. The culture midia was supplied with, 17-b-estradiol and progesterone. A growth curve was performed (24 hours, 48 hours and 72 hours) to verify the influence of the respective hormones in the cellular proliferation. As a positive control T-47-D cells derived from a hormone dependent metastatic breast carcinoma were used, and as negative control HN30 cells, derived from a tongue squamous cell carcinoma. 7 of 10 PAs were positive (4 in men and 3 in women) for RP and 8 of 8 PAs (4 in women and 4 in men) for RE. The statistical analysis verified a significant difference in the proliferative index between the control cells and the ones submitted to the action of the 17-b-estradiol and of the progesterone: for male derived lineage a difference was only observed in the last 72 hours. In the other hand, for the female derived lineage a significant difference was verified starting from 48 hours, suggesting that PA can be influenced by hormonal action.
318

Efeito da dose e do momento da administração de gonadotrofina coriônica eqüina (eCG) no protocolo de sincronização da ovulação para transferência de embriões em tempo fixo / Effect of dose and moment of equine chorionic gonadotrophin (eCG) administration in the synchronization of ovulation protocol for fixed-time embryo transfer

Everton Luiz Reis 21 January 2005 (has links)
Este estudo avaliou os efeitos da administração de diferentes doses de eCG em dois momentos distintos no protocolo de sincronização da ovulação para inovulação em tempo fixo. No dia 0, as receptoras foram tratadas com dispositivo intravaginal contendo progesterona (DIP) e 2,0 mg de Benzoato de Estradiol (BE) associados a 50 mg de progesterona (P4) IM. A partir desse momento, os animais foram divididos homogeneamente para receberem 0,15 mg de d-cloprostenol (PGF2&#945;) e 400, 500 ou 600 UI de eCG no dia 5 (G-400d5, n=101; G-500d5, n=98; G-600d5, n=100, respectivamente) ou no dia 8 (G-400d8, n=100; G-500d8, n=99; G-600d8, n=96, respectivamente; fatorial 3x2). O DIP foi retirado no dia 8 e foi administrado 1 mg de BE no dia 9. No dia 17 os animais foram submetidos a ultra-sonografia ovariana e os que apresentaram mais que um corpo lúteo (CL) ou CL único maior que 18 mm de diâmetro receberam um embrião produzido in vitro. Em um grupo de animais, colheu-se amostras de sangue no dia 17 para determinação da concentração plamática de P4 (CPP4). Os animais tratados com eCG no dia 5 apresentaram maior taxa de aproveitamento [87,0 (260/299) vs. 81,7% (241/295), P<0,05], tendência de maior taxa de concepção [51,8 (132/255) vs. 45,0% (108/295), P=0,07], maior taxa de prenhez [44,1 (132/299) vs. 36,6% (108/295), P<0,05], maior número de CL (1,74 ± 0,09 vs. 1,13 ± 0,03, P<0,05) e maior proporção de receptoras com CL único de maior tamanho [CL 22: 65,7 (111/169) vs. 43,1% (94/218), P<0,05] que os tratados no dia 8. Não se observou efeito de dose sobre a taxa de aproveitamento [400: 82,1 (165/201) vs. 500: 83,8 (165/197) vs. 600: 87,2% (171/196), P<0,05], de concepção [400: 51,8 (85/164) vs. 500: 44,1 (71/161) vs. 600: 49,4% (84/170), P<0,05], de prenhez [400: 42,3 (85/201) vs. 500: 36,0 (71/197) vs. 600: 42,9% (84/196), P<0,05] e sobre a quantidade de receptoras com CL único de maior tamanho [400: 46,8 (65/139) vs. 500: 54,9 (73/133) vs. 600: 57,4 (66/115), P<0,05]. Os animais tratados com 600 UI de eCG apresentaram maior número de CL que os que receberam 400 ou 500 UI (400: 1,17 ± 0,03 vs. 500: 1,33 ± 0,06 vs. 600: 1,82 ± 0,12, P<0,05). No grupo que se determinou a CPP4 verificou-se que os animais que receberam eCG no dia 5 apresentaram maiores CPP4 que os do dia 8 (4,68 ± 0,43 vs. 2,73 ± 0,17 ng/ml, P<0,05). As novilhas tratadas com 600 UI de eCG apresentaram maiores CPP que as tratados com 400 ou 500 UI (400: 2,96 ± 0,22 vs. 500: 3,45 ± 0,38 vs. 600: 4,69 ± 0,55, P<0,05). Receptoras com mais de 1 CL apresentaram tendência de menores perdas gestacionais entre 30 e 60 dias de gestação que as com CL único [10,2 (4/49) vs. 17,5% (33/189), P=0,0547]. Os resultados são indicativos de maior eficiência do protocolo de sincronização da ovulação para transferência de embriões em tempo fixo com o uso de eCG no dia 5. A dose de eCG não influenciou na eficiência do tratamento / The aim of this study was to compare the effects of different doses of eCG administrated at two moments in a fixed-time embryo transfer protocol. On day 0, the heifers received a progesterone releasing vaginal insert (PRVI) and an injection of 2.0 mg Estradiol Benzoate (EB) associated with 50 mg progesterone (P4) i.m. The animals were randomly assigned to six treatment groups in a tree by two factorial design to receive 0.15 mg d-cloprostenol (PGF2&#945;) i.m. and 400, 500 or 600 IU eCG on day 5 (G-400d5, n=101; G-500d5, n=98; G-600d5, n=100, respectively) or on day 8 (G-400d8, n=100; G-500d8, n=99; G-600d8, n=96, respectively). On day 8, the PRVI was removed and an injection of 1 mg EB was administered on day 9. On Day 17, all heifers were examined by ultrasonography to determine the number of CL and those with more than one CL or a single CL with a diameter ?18 mm received an in vitro produced embryo. A subset of heifers were bled on day 17 for plasma P4 determination. The animals treated with eCG on day 5 presented higher proportion of heifers selected/treated [87.0 (260/299) vs. 81.7% (241/295), P<0.05], tendency to higher proportion of heifers pregnant/transferred [51.8 (132/255) vs. 45.0% (108/295), P<0.1], higher proportion of heifers pregnant/treated [44.1 (132/299) vs. 36.6% (108/295), P<0.05], higher CL number (1.74 ± 0.09 vs. 1.13 ± 0.03, P<0.05) and higher proportion of recipients with larger single CL [CL 22: 65.7 (111/169) vs. 43.1% (94/218), P<0.05] than those treated with eCG on day 8. Dose effects were not observed in the proportion of heifers selected/treated [400: 82.1 (165/201) vs. 500: 83.8 (165/197) vs. 600: 87.2% (171/196), P<0.05], pregnant/transferred [400: 51.8 (85/164) vs. 500: 44.1 (71/161) vs. 600: 49.4% (84/170), P<0.05], pregnant/treated [400: 42.3 (85/201) vs. 500: 36.0 (71/197) vs. 600: 42.9% (84/196), P<0.05] and proportion of recipients with larger single CL [400: 46.8 (65/139) vs. 500: 54.9 (73/133) vs. 600: 57.4 (66/115), P<0.05]. The animals that received 600 IU eCG presented higher CL number than those received 400 and 500 IU (400: 1.17 ± 0.03 vs. 500: 1.33 ± 0.06 vs. 600: 1.82 ± 0.12, P<0.05). In a subset of heifers that was performed a plasma P4 determination, the group that received eCG on day 5 presented higher plasmatic P4 concentration than those received eCG on day 8 (4.68 ± 0.43 vs. 2.73 ± 0.17 ng/ml, P<0.05). The use of 600 IU eCG presented higher plasmatic P4 concentration than 500 and 600 IU (400: 2.96 ± 0.22 vs. 500: 3.45 ± 0.38 vs. 600: 4.69 ± 0.55, P<0.05). Recipients with more than 1 CL tended to present lower pregnancy losses between 30 and 60 days than those with a single CL [10.2 (4/49) vs. 17.5% (33/189), P=0.0547]. The results suggest higher efficiency in the synchronization of ovulation protocol for fixed-time embryo transfer with eCG administration on day 5. The dose of eCG did not affect the efficiency of treatment
319

A fase preparatória do parto de caprinos da raça Saanen. Manifestações clínicas indicadoras da parição iminente e avaliação do perfil hormonal / The preparatory phase of parturition in Saanen goats. Clinical signs of imminent labor and hormonal profile evaluation

Ana Paula Mazucco Prina 30 August 2007 (has links)
Com o objetivo de avaliar as modificações morfo-funcionais que ocorrem durante a fase preparatória do parto de caprinos, 18 fêmeas da raça Saanen foram examinadas duas vezes ao dia nos últimos 20 dias de gestação e, ao final do experimento, foram agrupadas segundo o momento que antecedia o parto, da seguinte forma: 16, 8, 6, 4 ,3, 2, 1 ½ , 1, ½ dia antes do parto e imediatamente antes da parição. Também foram colhidas amostras de plasma sangüíneo e de soro lácteo para a dosagem de progesterona, estradiol e cortisol e dos teores lácteos de cálcio. Durante o exame clínico foram avaliados os seguintes parâmetros: temperatura corpórea; relaxamento e movimentação dos Ligamentos Sacro-Isquiáticos; distensão e plenitude da glândula mamária e dos tetos; aspecto da secreção láctea pré-colostral e concentração de cálcio nela presente; modificações da vulva e do fluxo vaginal e determinação dos teores plasmáticos de cortisol, progesterona e estradiol. Ocorreram graduais relaxamento e aumento da movimentação dos Ligamentos Sacro-Isquiáticos, observados com maior intensidade a partir de 24 horas antes da parição, com grau máximo observado no momento do parto. Associada ao relaxamento e movimentação dos ligamentos, ocorreu diminuição gradual na capacidade dos animais em movimentar a cauda. A glândula mamária e os tetos foram tornando-se cada vez mais distendidos e plenos de acordo com a proximidade do momento da parição, sendo que a presença de edema na glândula mamária foi esporádica. A freqüência de cabras cuja secreção láctea foi classificada como colostro aumentou com a aproximação do parto, assim como os teores de cálcio na secreção pré-colostral. Houve um aumento significativo do fluxo vaginal nos animais examinados imediatamente antes da parição. O perfil hormonal sofreu influência da fase preparatória do parto, sendo que ocorreu diminuição dos teores plasmáticos médios de progesterona e aumento dos teores de estradiol e cortisol à medida que a parição se aproximava. A temperatura corpórea, o tamanho e o edema de vulva, o grau de flexibilidade da base da cauda e a coloração da mucosa vaginal não sofreram influência da fase preparatóra do parto. / With the aim to evaluate the morpho-functional changes of the caprine\'s parturition preparatory phase, 18 Saanen does were examined twice a day within the 20 finishing days of gestation and at the end of the experiment they were grouped according to the moment that preceded the birth (16, 8, 6, 4, 3, 2, 1 ½, 1, ½ days before parturition and immediately before labor). There were also picked samples of sanguine plasma and milky serum for the progesterone, oestradiol and cortisol dosage and milky calcium determinations. During the clinical exam the following parameters were evaluated: corporal temperature; relaxation and movement of the Sacrosciatic Ligaments; movement and flexibility of the tail; distention and filling of the udder and teats; appearance of the pre-colostral milky secretion and its calcium concentration; modifications of the vulva and vaginal discharge and determination of the plasmatic values of progesterone, oestradiol and cortisol. Gradual relaxation and increase of movement of the Sacrosciatic Ligaments occurred, observed with larger intensity starting from 24 hours before parturition, with maximum degree observed in the moment of the birth. A gradual decrease in the animals\' capacity on tail movement was observed associated to the relaxation and movement of the Sacrosciatic Ligaments. The mammary gland and teats became more distended and full in agreement with the proximity of the moment of parturition and the edema presence in the mammary gland was sporadic. The frequency of goats whose milky secretion was classified as colostrum increased with the approach of the labor, as well as the calcium tenors in the pre-colostral secretion. There was a significant increase of the vaginal discharge in the animals examined immediately before parturition. The hormonal profile suffered influence of the preparatory phase of labor, occurring decrease of the medium plasmatic tenors of progesterone and increase of the oestradiol and cortisol tenors as the parturition approaches. The corporal temperature, the size and vulva edema, the degree of flexibility of the tail and the coloration of vaginal mucous membrane didn\'t suffer influence of the preparatory stage of labor.
320

O uso de FSH exógeno estimula o crescimento folicular final e a função luteínica de vacas Holandesas em lactação sincronizadas para Inseminação Artificial em Tempo Fixo? / Does exogenous FSH increase the final follicular growth and lutea function for TAI in lactating Holstein cows?

Henderson Ayres 02 September 2011 (has links)
Vacas leiteira de alta produção têm apresentado declínio da eficiência reprodutiva. Essa redução é devido a causas multifatoriais, entre elas a baixa concentração de estradiol (E2) no proestro e a baixa concentração de progesterona (P4) no ciclo estral subsequentente. O objetivo deste trabalho foi comparar o uso de gonadotrofina exógena na dinâmica folicular e na taxa de prenhez de vacas submetidas ao protocolo Ovsynch (Experimento 1) ou a protocolos utilizando P4 e E2 (Experimento 2). No Experimento 1, animais de primeiro serviço foram pré-sincronizados com dois protocolos (Presynch ou Double-Ovsynch). Já os animais de segundo ou mais serviços foram resincronizados com o protocolo Resynch. Os animais receberam GnRH (1&ordm; GnRH), seguido 7 dias depois pela adiministração de prostaglandina F2&alpha; (PGF2&alpha;). Nesse momento os animais foram divididos homogeneamente por paridade e número de inseminação em um de dois tratamentos: sem FSH (Ovsynch, n = 561) ou com FSH (Ovsynch + FSH, n = 571). O segundo GnRH (2&ordm; GnRH) foi administrado 56 horas após a PGF2&alpha; e a inseminação em tempo fixo foi realizada 16 horas após. Amostras de sangue foram colhidas no 1&ordm; e no 2&ordm; GnRH, na PGF2&alpha; e 6 e 13 dias após o 2&ordm; GnRH para dosagem de P4. Ainda, no 2&ordm; GnRH dosou-se também E2 No Experimento 2, os animais foram sincronizados no dia 0 com um dispositivo de P4 associado a 2 mg de benzoato de estradiol. Oito dias após o dispositivo foi removido e os animais receberam uma dose de PGF2&alpha;. Neste mesmo momento, as vacas foram divididas homogeneamente por paridade, número de serviços prévios, escore de condição corporal e presença de CL no inicio do protocolo em três tratamentos: Controle (sem tratamento adicional; n = 232); eCG (400 UI de eCG; n = 232) e FSH (20 mg de FSH; n = 230). Todos os animais receberam GnRH e foram insemados 56h após a retirada do dispositivo. Foram colhidas amostras de sangue a cada 48h do dia 11 ao dia 22. No Experimento 1, não houve efeito do FSH na concetração sérica de E2 no 2&ordm; GnRH (P = 0,88), no tamanho do maior folículo no 2 &ordm; GnRH (P = 0,63), na taxa de ovulação ao 2&ordm; GnRH (P = 0,69) ou na concentração sérica de P4 no 6&ordm; (P = 0,15) e 13&ordm; (P = 0,36) dia após o 2&ordm; GnRH. A taxa de prenhez foi semelhante (P&gt; 0,05) entre os animais tratados com Ovsynch (36,2%) e Ovsynch + FSH (39,1%). No Experimento 2, os tratamentos não alteraram o diâmetro do folículo ovulatório (P = 0,15), o intervalo entre a remoção do dispositivo de P4 e a ovulação (P = 0,30) e a taxa de ovulação (P = 0,44). Não houve efeito de tratamento na concentração sérica de P4 (P = 0,15). A taxa de prenhez foi diferente entre os tratamentos aos 30 dias após a IATF (Controle = 28,0a vs FSH = 18,7b vs eCG = 29,7a %; P = 0,01), mas não aos 60 dias (Controle = 21,6 vs FSH = 16,1 vs eCG = 24,1%; P = 0,08) e na perda de gestacional (Controle = 18,8 vs FSH = 14,0 vs eCG = 18,4%; P = 0,39). Assim, o tratamento com FSH não estimulou o crescimento folicular final e a função luteínica de vacas leiteiras de alta produção sincronizadas com os protocolos Ovsynch e P4/E2. / Fertility in high-producing dairy cows has decreased over the years, which has been associated with reduced estradiol (E2) concentrations during proestrus and suboptimal progesterone (P4) concentrations during early stages of gestation. The objectives of the present study were to evaluate the effects of exogenous gonadotropins on follicular dynamics and risk of pregnancy per artificial insemination (P/AI) in cows subjected to the Ovsynch protocol (Experiment 1) or to a P4/E2-based timed AI protocol (experiment 2). In experiment 1, cows were enrolled in the Ovsynch protocol (GnRH, 7 d PGF2&alpha;, 56 h GnRH, 16 h IA) either after presynchronization (Presynch or Double-Ovsynch; first AI postpartum) or 32 d after previous AI. At the PGF2&alpha; injection, cows were blocked by parity and number of AI and, within each block, randomly allocated to eitherreceive 20 mg of FSH at the moment of the PGF2&alpha;(Ovsynch + FSH, n = 571) or to remain as untreated control (Ovsynch, n = 561). Blood was sampled at the 1st and 2nd GnRH and PGF2&alpha; injections, as well as on d 6 and 13 after the 2nd GnRH to access P4 and E2 (at the 2nd GnRH only) concentrations. In experiment 2, cows were received a P4 device and 2 mg of estradiol benzoate. The device was removed 8 d later concurrently with an injection of PGF2&alpha;, followed by an injection of GnRH and AI at 56 h.At the PGF2&alpha; injection, cows were blocked by parity, number of AI, body condition score, and presence of a CL at device insertion.Within each block, cows were randomly allocated to receive either 20 mg of FSH (FSH, n = 230), 400 IU of eCG (eCG, n = 232), or no additional treatment at the moment of the PGF2&alpha; (Control, n = 232). Blood was sampled at every 48 h from 1 to 12 d after AI. In experiment 1, there was no effect of FSH on serum E2 at the 2nd GnRH (P = 0.88), follicle diameter at the 2nd GnRH (P = 0.63), ovulatory response to the 2nd GnRH (P = 0.69), or serum P4 on d 6 (P = 0.15) and 13 (P = 0.36) after the 2nd GnRH. Also, P/AI was similar (P &gt; 0.05) between Ovsynch (36.2%) and Ovsynch + FSH (39.1%). In experiment 2, treatment did not affect ovulatory diameter (P = 0.15), interval from P4 device removal and ovulation (P = 0.30), ovulatory response to the 2nd GnRH (P = 0.44), and serum P4 (P = 0.15). Interestingly, treatment with FSH reduced (P = 0.01) P/AI on d 30 (Control = 28.0a vs. FSH = 18.7b vs. eCG = 29.7a %), but not on d 60after timed AI (Control = 21.6 vs. FSH = 16.1 vs. eCG = 24.1%; P = 0.08).The risk of pregnancy loss was not affected by treatment (Control = 18.8 vs. FSH = 14.0 vs. eCG = 18.4%; P = 0.39). In conclusion, treatment with FSH failed to enhance the final growth of the ovulatory follicle and did not improve luteal function after AI in high-producing dairy cows synchronized with either the Ovsynch or P4/E2-based timed AI protocols.

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