O efeito da angiotensina II na maturação nuclear de oócitos bovinos é mediado pelas prostaglandinas E2 e F2α
Autor(a) principal: | |
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Data de Publicação: | 2008 |
Tipo de documento: | Dissertação |
Idioma: | por |
Título da fonte: | Manancial - Repositório Digital da UFSM |
Texto Completo: | http://repositorio.ufsm.br/handle/1/10015 |
Resumo: | In mammals, it is well know that resumption of meiosis occurs after the preovulatory LH surge and results in germinal vesicle breakdown (GVBD), initiating the so-called oocyte maturation. However, the pathway by which this gonadotrophin acts is not completely clear. We have recently demonstrated that AngII plays an important role on the onset of ovulation in cattle, potentially acting as an intrafollicular LH mediator. We also observed that AngII prevents the inhibitory effect of follicular cells during bovine oocyte nuclear maturation in vitro. These results suggest that AngII plays a role in LH-induced resumption of meiosis in the bovine oocyte. The aim of this study was to verify the involvement of AngII in LH-induced meiosis resumption and test the hypothesis that prostaglandins E2 and F2α participates of AngII-induced meiosis resumption in bovine oocytes. In the first experiment, seven cows were superovulated with FSH and follicles larger than 12 mm in diameter were subjected to an intrafollicular injection of saralasin or saline. Follicles from the right ovary (n=17) where intrafollicular injected with saralasin (10μM) and follicles from the left ovary (n=17) were treated with saline (control group). A preovulatory LH surge was induced by im injection of a GnRH agonist (gonadorelin 100μg im) following the intrafollicular injections. Fifteen hours later, the animals were ovariectomized and the oocytes were recovered to evaluate the stage of meiotic maturation. All oocytes (n=12) were at germinal vesicle stage (GV) 15 hours after GnRH agonist injection in the saralasin group while in the control group (n=13) the oocytes were at the GVBD (30.8%) or Metaphase I (MI; 69.2%; P<0.001) stage. In other experiment, oocytes were co-cultured with follicular hemisections during 15 hours, to evaluate the role of prostaglandins mediating the effect of AngII on meiotic resumption. The inhibitory effects caused by follicular cells on oocyte nuclear maturation was prevented by adding 100pM of AngII to the culture medium (26.6% MI without AngII vs. 77.5% MI with AngII; P<0.001). However, when a nonselective ciclooxigenase (COX) inhibitor (10μM of indometacin) was present in the culture system with AngII and follicular hemisections, oocytes reached MI in a percentage (13.4%) significantly lower than without indometacin (P<0.001). Furthermore, when 1μM of PGE2 or PGF2α was added to the co-culture system with follicular cells, oocyte nuclear maturation rate followed the same pattern as the high maturation rate observed in the presence of AngII (PGE2 77.4%, PGF2α 70.0% and AngII 75.0% of MI). In conclusion, these results suggest that AngII mediates meiosis resumption induced by LH surge in bovine oocytes, which is dependent of PGE2 and PGF2α production by follicular cells. |
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O efeito da angiotensina II na maturação nuclear de oócitos bovinos é mediado pelas prostaglandinas E2 e F2αEffect of angiotensin II on bovine oocyte nuclear maturation mediated by PGE2 and PGF2αAngiotensina IISaralasinaMaturação nuclearInjeção intrafolicularPGE2PGF2αAngiotensin IISaralasinNuclear maturationIntrafollicular injectionPGE2PGF2αCNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIAIn mammals, it is well know that resumption of meiosis occurs after the preovulatory LH surge and results in germinal vesicle breakdown (GVBD), initiating the so-called oocyte maturation. However, the pathway by which this gonadotrophin acts is not completely clear. We have recently demonstrated that AngII plays an important role on the onset of ovulation in cattle, potentially acting as an intrafollicular LH mediator. We also observed that AngII prevents the inhibitory effect of follicular cells during bovine oocyte nuclear maturation in vitro. These results suggest that AngII plays a role in LH-induced resumption of meiosis in the bovine oocyte. The aim of this study was to verify the involvement of AngII in LH-induced meiosis resumption and test the hypothesis that prostaglandins E2 and F2α participates of AngII-induced meiosis resumption in bovine oocytes. In the first experiment, seven cows were superovulated with FSH and follicles larger than 12 mm in diameter were subjected to an intrafollicular injection of saralasin or saline. Follicles from the right ovary (n=17) where intrafollicular injected with saralasin (10μM) and follicles from the left ovary (n=17) were treated with saline (control group). A preovulatory LH surge was induced by im injection of a GnRH agonist (gonadorelin 100μg im) following the intrafollicular injections. Fifteen hours later, the animals were ovariectomized and the oocytes were recovered to evaluate the stage of meiotic maturation. All oocytes (n=12) were at germinal vesicle stage (GV) 15 hours after GnRH agonist injection in the saralasin group while in the control group (n=13) the oocytes were at the GVBD (30.8%) or Metaphase I (MI; 69.2%; P<0.001) stage. In other experiment, oocytes were co-cultured with follicular hemisections during 15 hours, to evaluate the role of prostaglandins mediating the effect of AngII on meiotic resumption. The inhibitory effects caused by follicular cells on oocyte nuclear maturation was prevented by adding 100pM of AngII to the culture medium (26.6% MI without AngII vs. 77.5% MI with AngII; P<0.001). However, when a nonselective ciclooxigenase (COX) inhibitor (10μM of indometacin) was present in the culture system with AngII and follicular hemisections, oocytes reached MI in a percentage (13.4%) significantly lower than without indometacin (P<0.001). Furthermore, when 1μM of PGE2 or PGF2α was added to the co-culture system with follicular cells, oocyte nuclear maturation rate followed the same pattern as the high maturation rate observed in the presence of AngII (PGE2 77.4%, PGF2α 70.0% and AngII 75.0% of MI). In conclusion, these results suggest that AngII mediates meiosis resumption induced by LH surge in bovine oocytes, which is dependent of PGE2 and PGF2α production by follicular cells.Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorEm mamíferos, é bem estabelecido que o reinício da meiose ocorre após o pico préovulatório de LH e resulta no rompimento da vesícula germinativa (RVG), iniciando a maturação do oócito. Entretanto, a via pela qual essa gonadotrofina atua não está completamente elucidada. Nosso grupo demonstrou que a angiotensina II (AngII) apresenta uma importante função no início da ovulação em bovinos, potencialmente atuando como um mediador intrafolicular do LH. Nós também observamos que a AngII previne o efeito inibitório das células foliculares durante a maturação nuclear in vitro de oócitos bovinos. Estes resultados sugerem que a AngII apresenta uma função importante durante o reinício da meiose induzido pelo LH em oócitos bovinos. Portanto, os objetivos deste estudo foram verificar a participação da AngII no reinício da meiose induzido pelo pico ovulatório de LH, e investigar o envolvimento das prostaglandinas E2 e F2α como mediadores da AngII para desencadear o reinício da meiose em oócitos bovinos. No primeiro experimento, sete vacas foram superovuladas com FSH e os folículos maiores que 12mm de diâmetro foram submetidos a uma injeção intrafolicular de saralasina ou NaCl 0,9%. Os folículos do ovário direito (n=17) receberam uma injeção intrafolicular de saralasina (10μM) e os do ovário esquerdo (n=17) foram injetados com NaCl 0,9% (grupo controle). Um pico de LH foi induzido pela administração IM de um agonista do GnRH (gonadorelina 100μg) imediatamente após as injeções intrafoliculares. Quinze horas após, os animais foram ovariectomizados e os oócitos foram recuperados para avaliar o estádio da maturação nuclear. Todos os oócitos do grupo saralasina (n=12) estavam no estádio de vesícula germinativa (VG) 15 horas após a administração IM de um agonista do GnRH enquanto que no grupo controle (n=13) os oócitos estavam no estádio de RVG (30,8%) ou Metáfase I (MI; 69,2%; P<0,001). Em outro experimento, oócitos foram co-cultivados com metades foliculares durante 15 horas para avaliar a participação das prostaglandinas como mediadores do efeito da AngII sobre o reinício da meiose. O efeito inibitório causado pelas células foliculares sobre a maturação nuclear do oócito foi prevenido pela adição de 100pM de AngII ao meio de cultivo (26,6% de MI sem AngII vs. 77,5% de MI com AngII; P<0,001). Entretanto, quando um inibidor não seletivo da COX (10μM de indometacina) foi adicionado ao sistema de cultivo contendo AngII e metades foliculares, os oócitos atingiram MI em uma percentagem (13,4%) significativamente mais baixa que sem indometacina (P<0,001). Além disso, quando 1μM de PGE2 ou PGF2α foram adicionados ao sistema de co-cultivo in vitro com metades foliculares, a taxa de maturação nuclear dos oócitos seguiu o mesmo padrão observado na presença de AngII (PGE2 77,4%, PGF2α 70,0% e AngII 75,0% de MI). Portanto, este estudo demonstra que o reinício da meiose em oócitos bovinos, induzido pelo pico ovulatório de LH, requer AngII, e que as prostaglandinas E2 e F2α participam dessa ação.Universidade Federal de Santa MariaBRMedicina VeterináriaUFSMPrograma de Pós-Graduação em Medicina VeterináriaOliveira, João Francisco Coelho dehttp://lattes.cnpq.br/1168979725730267Mezzalira, Alceuhttp://lattes.cnpq.br/2481625293830872Maciel, Marlon Nadalhttp://lattes.cnpq.br/3489544811362550Barreta, Marcos Henrique2017-06-142017-06-142008-02-27info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfapplication/pdfBARRETA, Marcos Henrique. Effect of angiotensin II on bovine oocyte nuclear maturation mediated by PGE2 and PGF2α. 2008. 61 f. Dissertação (Mestrado em Medicina Veterinária) - Universidade Federal de Santa Maria, Santa Maria, 2008.http://repositorio.ufsm.br/handle/1/10015porinfo:eu-repo/semantics/openAccessreponame:Manancial - Repositório Digital da UFSMinstname:Universidade Federal de Santa Maria (UFSM)instacron:UFSM2022-01-07T19:27:42Zoai:repositorio.ufsm.br:1/10015Biblioteca Digital de Teses e Dissertaçõeshttps://repositorio.ufsm.br/ONGhttps://repositorio.ufsm.br/oai/requestatendimento.sib@ufsm.br||tedebc@gmail.comopendoar:2022-01-07T19:27:42Manancial - Repositório Digital da UFSM - Universidade Federal de Santa Maria (UFSM)false |
dc.title.none.fl_str_mv |
O efeito da angiotensina II na maturação nuclear de oócitos bovinos é mediado pelas prostaglandinas E2 e F2α Effect of angiotensin II on bovine oocyte nuclear maturation mediated by PGE2 and PGF2α |
title |
O efeito da angiotensina II na maturação nuclear de oócitos bovinos é mediado pelas prostaglandinas E2 e F2α |
spellingShingle |
O efeito da angiotensina II na maturação nuclear de oócitos bovinos é mediado pelas prostaglandinas E2 e F2α Barreta, Marcos Henrique Angiotensina II Saralasina Maturação nuclear Injeção intrafolicular PGE2 PGF2α Angiotensin II Saralasin Nuclear maturation Intrafollicular injection PGE2 PGF2α CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA |
title_short |
O efeito da angiotensina II na maturação nuclear de oócitos bovinos é mediado pelas prostaglandinas E2 e F2α |
title_full |
O efeito da angiotensina II na maturação nuclear de oócitos bovinos é mediado pelas prostaglandinas E2 e F2α |
title_fullStr |
O efeito da angiotensina II na maturação nuclear de oócitos bovinos é mediado pelas prostaglandinas E2 e F2α |
title_full_unstemmed |
O efeito da angiotensina II na maturação nuclear de oócitos bovinos é mediado pelas prostaglandinas E2 e F2α |
title_sort |
O efeito da angiotensina II na maturação nuclear de oócitos bovinos é mediado pelas prostaglandinas E2 e F2α |
author |
Barreta, Marcos Henrique |
author_facet |
Barreta, Marcos Henrique |
author_role |
author |
dc.contributor.none.fl_str_mv |
Oliveira, João Francisco Coelho de http://lattes.cnpq.br/1168979725730267 Mezzalira, Alceu http://lattes.cnpq.br/2481625293830872 Maciel, Marlon Nadal http://lattes.cnpq.br/3489544811362550 |
dc.contributor.author.fl_str_mv |
Barreta, Marcos Henrique |
dc.subject.por.fl_str_mv |
Angiotensina II Saralasina Maturação nuclear Injeção intrafolicular PGE2 PGF2α Angiotensin II Saralasin Nuclear maturation Intrafollicular injection PGE2 PGF2α CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA |
topic |
Angiotensina II Saralasina Maturação nuclear Injeção intrafolicular PGE2 PGF2α Angiotensin II Saralasin Nuclear maturation Intrafollicular injection PGE2 PGF2α CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA |
description |
In mammals, it is well know that resumption of meiosis occurs after the preovulatory LH surge and results in germinal vesicle breakdown (GVBD), initiating the so-called oocyte maturation. However, the pathway by which this gonadotrophin acts is not completely clear. We have recently demonstrated that AngII plays an important role on the onset of ovulation in cattle, potentially acting as an intrafollicular LH mediator. We also observed that AngII prevents the inhibitory effect of follicular cells during bovine oocyte nuclear maturation in vitro. These results suggest that AngII plays a role in LH-induced resumption of meiosis in the bovine oocyte. The aim of this study was to verify the involvement of AngII in LH-induced meiosis resumption and test the hypothesis that prostaglandins E2 and F2α participates of AngII-induced meiosis resumption in bovine oocytes. In the first experiment, seven cows were superovulated with FSH and follicles larger than 12 mm in diameter were subjected to an intrafollicular injection of saralasin or saline. Follicles from the right ovary (n=17) where intrafollicular injected with saralasin (10μM) and follicles from the left ovary (n=17) were treated with saline (control group). A preovulatory LH surge was induced by im injection of a GnRH agonist (gonadorelin 100μg im) following the intrafollicular injections. Fifteen hours later, the animals were ovariectomized and the oocytes were recovered to evaluate the stage of meiotic maturation. All oocytes (n=12) were at germinal vesicle stage (GV) 15 hours after GnRH agonist injection in the saralasin group while in the control group (n=13) the oocytes were at the GVBD (30.8%) or Metaphase I (MI; 69.2%; P<0.001) stage. In other experiment, oocytes were co-cultured with follicular hemisections during 15 hours, to evaluate the role of prostaglandins mediating the effect of AngII on meiotic resumption. The inhibitory effects caused by follicular cells on oocyte nuclear maturation was prevented by adding 100pM of AngII to the culture medium (26.6% MI without AngII vs. 77.5% MI with AngII; P<0.001). However, when a nonselective ciclooxigenase (COX) inhibitor (10μM of indometacin) was present in the culture system with AngII and follicular hemisections, oocytes reached MI in a percentage (13.4%) significantly lower than without indometacin (P<0.001). Furthermore, when 1μM of PGE2 or PGF2α was added to the co-culture system with follicular cells, oocyte nuclear maturation rate followed the same pattern as the high maturation rate observed in the presence of AngII (PGE2 77.4%, PGF2α 70.0% and AngII 75.0% of MI). In conclusion, these results suggest that AngII mediates meiosis resumption induced by LH surge in bovine oocytes, which is dependent of PGE2 and PGF2α production by follicular cells. |
publishDate |
2008 |
dc.date.none.fl_str_mv |
2008-02-27 2017-06-14 2017-06-14 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/masterThesis |
format |
masterThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
BARRETA, Marcos Henrique. Effect of angiotensin II on bovine oocyte nuclear maturation mediated by PGE2 and PGF2α. 2008. 61 f. Dissertação (Mestrado em Medicina Veterinária) - Universidade Federal de Santa Maria, Santa Maria, 2008. http://repositorio.ufsm.br/handle/1/10015 |
identifier_str_mv |
BARRETA, Marcos Henrique. Effect of angiotensin II on bovine oocyte nuclear maturation mediated by PGE2 and PGF2α. 2008. 61 f. Dissertação (Mestrado em Medicina Veterinária) - Universidade Federal de Santa Maria, Santa Maria, 2008. |
url |
http://repositorio.ufsm.br/handle/1/10015 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf application/pdf |
dc.publisher.none.fl_str_mv |
Universidade Federal de Santa Maria BR Medicina Veterinária UFSM Programa de Pós-Graduação em Medicina Veterinária |
publisher.none.fl_str_mv |
Universidade Federal de Santa Maria BR Medicina Veterinária UFSM Programa de Pós-Graduação em Medicina Veterinária |
dc.source.none.fl_str_mv |
reponame:Manancial - Repositório Digital da UFSM instname:Universidade Federal de Santa Maria (UFSM) instacron:UFSM |
instname_str |
Universidade Federal de Santa Maria (UFSM) |
instacron_str |
UFSM |
institution |
UFSM |
reponame_str |
Manancial - Repositório Digital da UFSM |
collection |
Manancial - Repositório Digital da UFSM |
repository.name.fl_str_mv |
Manancial - Repositório Digital da UFSM - Universidade Federal de Santa Maria (UFSM) |
repository.mail.fl_str_mv |
atendimento.sib@ufsm.br||tedebc@gmail.com |
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1805922172506472448 |