RESUMO

Pigs have the highest percentage of embryonic death not associated with specific diseases of all livestock species, at 20-45%. During gestation processes, a series of complex alterations can arise, including embryonic migration and elongation, maternal immunological recognition of pregnancy, and embryonic competition for implantation sites and subsequent nutrition requirements and development. Immune cells and cytokines act as mediators between other molecules in highly complex interactions between various cell types. However, other non-immune cells, such as trophoblast cells, are important in immune pregnancy regulation. Numerous studies have shed light on the crucial roles of several cytokines that regulate the inflammatory processes that characterize the interface between the fetus and the mother throughout normal porcine gestation, but most of these reports are limited to the implantational and peri-implantational periods. Increase in some proinflammatory cytokines have been found in other gestational periods, such as placental remodeling. Porcine immune changes during delivery have not been studied as deeply as in other species. This review details some of the immune system cells actively involved in the fetomaternal interface during porcine gestation, as well as the principal cells, cytokines, and molecules, such as antibodies, that play crucial roles in sow pregnancy, both in early and mid-to-late gestation.

RESUMO

Os diferentes aspectos das diferentes placentas dos mamíferos domésticos têm sido estudados por vários autores. A placenta dos suínos domésticos é caracterizada por ser do tipo epiteliocorial difusa. No endométrio há a presença de dobras macroscópicas com inúmeras glândulas uterinas, cuja área fetal correspondente se expande formando as aréolas e o seu lume é rico em uteroferrina, uma glicoproteína envolvida no transporte de ferro. Em relaçäo às diferentes regiöes placentárias (areolar e interareolar), distingüem-se áreas diferenciadas de microvascularizaçäo e os capilares convergem para a superfície dos vilos, ao longo das dobras secundárias

Assuntos

RESUMO

The placental haematomes execute unknown functions in some species. In ewe this structures occur in an arcade zone of the placenton (tips of the maternal septa), region where occurs the trophoblastic erythrophagocytosis. The real function of the haematome is unknown in bufaline specie, which is very important in our study. There is great possibility of maternal-fetal transfer of iron across of these structures, that occur by extravasated maternal blood in determinate regions of the villi (maternal-fetal junction). Water buffalo placentae were used within 4-5, 7-8 and 9-10 months of pregnancy, immediately after sacrifice and fixed by perfusion the uterine vessels with paraformoldehyde 4% in 0,1M phosphate buffer; after perfusion, the placentons were fixed for light microscopy by immersion, too. After 24 hours, the pieces were cut and processed for embed in paraplast and historesin and staining by HE, Toluidine blue, Perls and PAS reactions, Gomori"s and Mallory"s tricrome. The haematomes were present in determinate regions of the placenton, which had haemorragic areas within the uterine and trophoblastic epithelium, in placentae of 7-8, 9-10 months of pregnancy. Maternal red cells were found into the trophoblastic cells, clearing the erythrophagocytosis.

Os hematomas placentários executam funções desconhecidas em várias espécies. Na ovelha, estas estruturas ocorrem na zona arcada do placentônio (topos dos septos maternos), região onde ocorre a eritrofagocitose trofoblástica. A função real do hematoma é desconhecida na espécie bufalina, a qual é muito importante no nosso estudo. Há grande possibilidade de transferência de ferro para o feto através destas estruturas, que ocorrem por extravasamento de sangue materno em determinadas regiões dos vilos (junção materno-fetal). Foram usadas placentas de búfalos entre 4-5, 7-8, 9-10 meses de prenhez, imediatamente após sacrifício e fixadas por perfusão de vasos uterinos com paraformaldeído a 4% em 0,1M em tampão fosfato; após a perfusão, os placentônios foram fixados por imersão para microscopia de luz. Depois de 24 horas, as amostras foram cortadas e processadas para inclusão em "paraplast" e "historesina" e coradas pelos métodos de HE, azul de Toluidina, reações de Perls e PAS e tricromos de Gomori e Mallory. Os hematomas estavam presentes em determinadas regiões do placentônio, nos quais havia áreas hemorrágicas entre o epitélio uterino e o trofoblástico, nas placentas de 7-8 e 9-10 meses de prenhez. Células sangüíneas maternas foram encontradas nas células trofoblásticas, elucidando a eritrofagocitose.