Research On The Relationship Of The Amnion And Placenta Facors And The Occurrence Mechanism Of Oligohydramnios

ObjectiveTo investigate the relationship of themorphologic, histochemistric, immunohistochemistric and Fas/FasL changes of the amniotic membrane cells and placenta villi and oligohydramnios (ROH).Materials and MethodsThere were 60 cases in full term pregnancy in this study.30 ROH cases were taken as an experiment group (ROH group), another 30 non-ROH cases as a control group. The amnion and placenta of the two groups were selected and embed in paraffin and sliced. All slices carefully selected (10 slices/case·method) were stained with HE, three histochemistric methods (AKP-PAS, AB-PAS and MGP) and immunohistochemistric method (Fas/FasL). The slices were observed under the microscope, and small amount of important structures were tested and analyzed quantitatively. Two pieces of the amniotic and placenta from 5 ROH cases and 5 non-ROH cases were sampled respectively and made into ultrathin slice and observed under an electron microscope.ResultsIn the ROH group, the amniotic cells became larger and their cytoplasm became bubble. The AKP reactions of amniotic cells and trophoblast on the placenta villi were weak. DNAs in the nucleus were found agglomerate as MGP stained. There was a significant statistical difference between the ROH group and the control group(P<0.05, P<0.01).In the ROH group, the FasL was expressed weakly and the Fas was expressed strongly as Fas/FasL stained, the apoptosis of syncytiotrophoblasts and amniocytes were increased. Compared with the control group, the optical density(OD) of Fas/FasL were significantly different (P<0.05, P<0.01). The synctail knots of ROH group were increased and the vasoculo-syncytial membrane became thicker, a significant difference(P<0.05, P<0.01)was found compared with the control group.Under the electric microscope, the desmosomes of ROH group among adjacent amniocytes became rare and their linking was loose. The microvilli on the amniocytes and syncytiotrophoblasts were short and rare and the normal shapes were lost.In the ROH group, the chondriosomes were swelled and the base endoplasms were edematous, the crests were faint and even solidified and shrunk; The endoplasmic reticulums were dilated and degranulated, the chromosomes were agglutinated along the edge, and the apoptosical bodies were formed.ConclusionsThe experiment highly suggests that the dysfunction of placenta and amnion and the fetal blood hypoxia caused by the apoptosis of amniotic membrane and placenta cells, the damage of the organelles and the lesion of basement membrane and the thickening of vasoculo-syncytial membrane might be the key factors of ROH.