PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

Animal models are essential to understand healthy human placentation. Guinea pig related rodents became on focus for such purposes. In particular, processes of trophoblast invasion are similar. The latter is associated with a specialized area, the subplacenta. Since previous results showed differences between the guinea pig and its close relative Galea spixii, we aimed to study subplacental development with more detail. We investigated 16 pregnant females of 14 to 55 days of gestation by means of histology, morphometrics, immunohistochemistry and electron microscopy. The overlap between the fetomaternal blood systems resulted as intimate, suggesting some exchange processes. Proliferation was revealed by three independent methods, being most active in early and mid-gestation, which was in accordance to former results. Though degeneration of tissues took place, the subplacenta was maintained towards term with access to the fetal vascularization, supporting a hypothesis about the release of substances to the fetal unit in advanced gestation. In contrast to other species, the extraplacental trophoblast showed a shift from syncytial streamers to giant cells during mid-gestation. Views on placentation in caviomorphs were influenced by the guinea pig, but our data supported recent studies that the subplacenta had a much greater placidity. In regard to subplacental grow, degeneration and likely also exchange processes, Galea and other species showed a more basal pattern of caviomorphs than the guinea pig. Such differences should be considered, when choosing most adequate animal models for special purposes in comparison to human placentation.

• Placenta cytotrophoblast syncytiotrophoblast trophoblast invasion guinea pig Galea spixii animal model

Abstract in Portuguese:

Animal models are essential to understand healthy human placentation. Guinea pig related rodents became on focus for such purposes. In particular, processes of trophoblast invasion are similar. The latter is associated with a specialized area, the subplacenta. Since previous results showed differences between the guinea pig and its close relative Galea spixii, we aimed to study subplacental development with more detail. We investigated 16 pregnant females of 14 to 55 days of gestation by means of histology, morphometrics, immunohistochemistry and electron microscopy. The overlap between the fetomaternal blood systems resulted as intimate, suggesting some exchange processes. Proliferation was revealed by three independent methods, being most active in early and mid-gestation, which was in accordance to former results. Though degeneration of tissues took place, the subplacenta was maintained towards term with access to the fetal vascularization, supporting a hypothesis about the release of substances to the fetal unit in advanced gestation. In contrast to other species, the extraplacental trophoblast showed a shift from syncytial streamers to giant cells during mid-gestation. Views on placentation in caviomorphs were influenced by the guinea pig, but our data supported recent studies that the subplacenta had a much greater placidity. In regard to subplacental grow, degeneration and likely also exchange processes, Galea and other species showed a more basal pattern of caviomorphs than the guinea pig. Such differences should be considered, when choosing most adequate animal models for special purposes in comparison to human placentation.

• Placenta citotrofoblasto sinciciotrofoblasto invasão trofoblástica preá Galea spixii modelo animal

Abstract in English:

ABSTRACT.- Rici R.E.G., Facciotti P.R., Franciolli A.L.R., Mançanares A.C.F., Pastori J., Maria D.A. & Miglino M.A. 2011. [Proliferative analysis of trophoblastic cells in cattle.] Análise proliferativa nas células trofoblásticas em bovinos.] Análise proliferativa nas células trofoblásticas em bovinos. Pesquisa Veterinária Brasileira 31(6):538-542. Programa de Pós-Graduação em Anatomia dos Animais Domésticos e Silvestres, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitária, São Paulo, SP 05508-270, Brazil. E-mail: roseeli@usp.br The aim of the present study was to evaluate the cell proliferative activity, by AgNORs number, in different regions of bovine placenta throughout gestation. A total of 28 bovine placentas were separated into four groups: group I (60 to 120 days), group II (121 to 170 days), group III (171 to 220 days), and group IV (221 to 290 days). It was found a greater number of AgNORs in giant trophoblastic cells (GTC) when compared with mononuclear trophoblastic cells (MTC) (p<0,001) in all regions and gestational groups analyzed, that confirms their intensive synthesis activity in trophoblast epithelium. The central region of the placentome begins an intense proliferative activity in group II, observed by clusters, while placentomes edges showed a higher number of clusters on group III. These data suggest that the central region of the placentomes began an intense proliferative activity prior to its edge, both declines at the end of pregnancy. Interplacentomal area showed a higher number of AgNORs in the group IV, suggesting a higher proliferative activity of these cells at the end of pregnancy. The results of this study indicate that the proliferative activity, as determined by the amount of intranuclear AgNORs, exhibits patterns that are not only specific to each type of trophoblastic cells, but also for each specific region of bovine placenta throughout pregnancy.

• Placentome trophoblastic cells células trofoblásticas placentônio

Abstract in Portuguese:

RESUMO.- Rici R.E.G., Facciotti P.R., Franciolli A.L.R., Mançanares A.C.F., Pastori J., Maria D.A. & Miglino M.A. 2011. [Proliferative analysis of trophoblastic cells in cattle.] Análise proliferativa nas células trofoblásticas em bovinos.] Análise proliferativa nas células trofoblásticas em bovinos. Pesquisa Veterinária Brasileira 31(6):538-542. Programa de Pós-Graduação em Anatomia dos Animais Domésticos e Silvestres, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitária, São Paulo, SP 05508-270, Brazil. E-mail: roseeli@usp.br Este estudo teve como objetivo analisar atividade proliferativa das células trofoblásticas, através da quantificação de AgNORs, em diferentes regiões da placenta bovina ao longo da gestação. Foram utilizados 28 úteros, sendo estes agrupados de acordo com as idades gestacionais: grupo I (60-120 dias); II (121- 170 dias); III (171-220 dias) e IV (221-290 dias). Foi encontrado um número significativamente maior de AgNORs nas células trofoblásticas gigantes (CTG) em relação às mononucleadas (CTM) (p<0,001) em todas as regiões e grupos gestacionais analisados, o que confirma sua intensa atividade de síntese no epitélio trofoblástico. A região central do placentônio inicia uma atividade proliferativa mais intensa já no grupo II, observada pelo número de clusters, enquanto que a margem do placentônio apresenta uma maior quantidade de clusters no grupo III. Estes dados sugerem que a região central do placentônio inicia uma intensa atividade proliferativa anteriormente a sua margem, ambas declinando no final da gestação. A área interplacentomal apresentou um maior número de AgNORs no último grupo gestacional, sugerindo uma maior atividade proliferativa dessas células no final da prenhez. Os resultados deste estudo indicam que a atividade proliferativa, determinada pela quantidade de AgNORs intranucleares, exibe padrões que são específicos não somente para cada tipo de célula trofoblástica, mas também para cada região específica da placenta bovina ao longo da gestação.

Abstract in English:

ABSTRACT.- Cazerta S.M.M., Miglino M.A., Marques R.S., Vulcano M. & Pereira F.T.V. 2007. [Characterization of hemophagous areas of the bovine placenta.] Caracterização das áreas hemófagas da placenta bovina. Pesquisa Veterinária Brasileira 26(6):229-235. Faculdade de Zootecnia, Campus Dracena, Unesp, Rod. Com. João Ribeiro de Barros, SP294 Km 651, Dracena, SP 17900-000, Brazil. E-mail: fverechia@dracena.unesp.br The specific region of maternal fetal interface needs to be clarified and corresponds to the “arcade zone” of sheep and goat placentomes. In small ruminants that area is also characterized by macroscopic blood extravasation (hemophagous areas). This occurs possibly because the iron is transferred to the embryo by trophoblastic erytrophagocytosis in these hemophagous placental areas. In order to investigate the hemophagous placental areas in cattle, placentomes of 34 pregnant Bos indicus cows (2-3, 4-6, 7-8 and 9 months of gestation) were analyzed. They were fixed by perfusion with 10% formaldehyde aqueous solution and 4% paraformoldehyde in PBS, pH 7.4, 0.1M, processed and stained for light microscopy and histochemistry. The methodology used allowed to observe placental haematomes between the uterine and trophoblastic epithelium since 3 months of pregnancy. Erythrocytes had been found in the trophoblastic cells, elucidating the erytrophagocytosis. Through Perl’s histochemical reaction it was possible to prove the existence of ferric iron in the trophoblastic cells. The PAS reaction was positive staining mucoid substance in the epithelial cells, especially in the binucleate cells of the fetal epithelium. Based on histology and histochemistry, it can be inferred that the hemophagous areas are important sites for iron transfer in the bovine placenta.

• Erythrophagocytosis hemophagous areas bovine placenta reproduction trophoblast

Abstract in Portuguese:

ABSTRACT.- Cazerta S.M.M., Miglino M.A., Marques R.S., Vulcano M. & Pereira F.T.V. 2007. [Characterization of hemophagous areas of the bovine placenta.] Caracterização das áreas hemófagas da placenta bovina. Pesquisa Veterinária Brasileira 26(6):229-235. Faculdade de Zootecnia, Campus Dracena, Unesp, Rod. Com. João Ribeiro de Barros, SP294 Km 651, Dracena, SP 17900-000, Brazil. E-mail: fverechia@dracena.unesp.br The specific region of maternal fetal interface needs to be clarified and corresponds to the “arcade zone” of sheep and goat placentomes. In small ruminants that area is also characterized by macroscopic blood extravasation (hemophagous areas). This occurs possibly because the iron is transferred to the embryo by trophoblastic erytrophagocytosis in these hemophagous placental areas. In order to investigate the hemophagous placental areas in cattle, placentomes of 34 pregnant Bos indicus cows (2-3, 4-6, 7-8 and 9 months of gestation) were analyzed. They were fixed by perfusion with 10% formaldehyde aqueous solution and 4% paraformoldehyde in PBS, pH 7.4, 0.1M, processed and stained for light microscopy and histochemistry. The methodology used allowed to observe placental haematomes between the uterine and trophoblastic epithelium since 3 months of pregnancy. Erythrocytes had been found in the trophoblastic cells, elucidating the erytrophagocytosis. Through Perl’s histochemical reaction it was possible to prove the existence of ferric iron in the trophoblastic cells. The PAS reaction was positive staining mucoid substance in the epithelial cells, especially in the binucleate cells of the fetal epithelium. Based on histology and histochemistry, it can be inferred that the hemophagous areas are important sites for iron transfer in the bovine placenta.

Abstract in English:

ABSTRACT.- Iturrizaga D.M., Verechia F.T., Santos T.C., Bombonato P.P., Teixeira D.G. & Miglino M.A. 2007. The materno-fetal interface in llama (Lama guanicoe glama). Pesquisa Veterinária Brasileira 27(6):221-228. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270, Brazil. E-mail: miglino@usp.br Samples from 9 llamas (28 through 36 weeks of gestation) were collected and fixed in 4% buffered paraformaldehyde (light microscopy) and in 2.5% buffered glutaraldehyde (transmission and scanning electron microscopy). The material was processed in paraplast and slides (5mm) were stained with HE, PAS, Masson-Trichrome, acid phosphatase and Perl´s. The uteroferrin was immunolocalized. The results show that llama placenta is chorioallantoic, diffuse, folded and epitheliochorial, and the fetus is covered with an epidermal membrane. The trophoblast cells have variable morphology: cubic, rounded and triangular cells, with cytoplasm containing PAS-positive granules. Binucleated cells with large cytoplasm and rounded nuclei, as well as giant trophoblastic cells with multiple nuclei were also observed. Numerous blood vessels were observed beneath the cells of the uterine epithelium and around the chorionic subdivided branches. Glandular activity was shown by PAS, Perl´s, and acid phosphatase positive reactions in the cytoplasm and glandular lumen, and by immunolocalization of the uteroferrin in the glandular epithelium. The uterine glands open in spaces formed by the areoles, which are filled by PAS-positive material. The llama fetus was covered by the epidermal membrane, composed of stratified epithelium, with up to seven layers of mono-, bi- or trinucleated cells. The high level of maternal and fetal vascularization surfaces indicates an intense exchange of substances across both surfaces. The metabolic activity shown in the uterine glands suggests an adaptation of the gestation to the high altitudes of the natural habitat of this species.

• Placenta llama trophoblast uteroferrin ephiteliochorial morphology

Abstract in Portuguese:

ABSTRACT.- Iturrizaga D.M., Verechia F.T., Santos T.C., Bombonato P.P., Teixeira D.G. & Miglino M.A. 2007. The materno-fetal interface in llama (Lama guanicoe glama). Pesquisa Veterinária Brasileira 27(6):221-228. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270, Brazil. E-mail: miglino@usp.br Samples from 9 llamas (28 through 36 weeks of gestation) were collected and fixed in 4% buffered paraformaldehyde (light microscopy) and in 2.5% buffered glutaraldehyde (transmission and scanning electron microscopy). The material was processed in paraplast and slides (5mm) were stained with HE, PAS, Masson-Trichrome, acid phosphatase and Perl´s. The uteroferrin was immunolocalized. The results show that llama placenta is chorioallantoic, diffuse, folded and epitheliochorial, and the fetus is covered with an epidermal membrane. The trophoblast cells have variable morphology: cubic, rounded and triangular cells, with cytoplasm containing PAS-positive granules. Binucleated cells with large cytoplasm and rounded nuclei, as well as giant trophoblastic cells with multiple nuclei were also observed. Numerous blood vessels were observed beneath the cells of the uterine epithelium and around the chorionic subdivided branches. Glandular activity was shown by PAS, Perl´s, and acid phosphatase positive reactions in the cytoplasm and glandular lumen, and by immunolocalization of the uteroferrin in the glandular epithelium. The uterine glands open in spaces formed by the areoles, which are filled by PAS-positive material. The llama fetus was covered by the epidermal membrane, composed of stratified epithelium, with up to seven layers of mono-, bi- or trinucleated cells. The high level of maternal and fetal vascularization surfaces indicates an intense exchange of substances across both surfaces. The metabolic activity shown in the uterine glands suggests an adaptation of the gestation to the high altitudes of the natural habitat of this species.