Expression Of NOS In Foetal Placenta In Cows With Retention Of Fetal Membranes

Cow with retention of fetal membranes(RFM) is one of the frequent disease in obstetrics, it influences the breeding potential and performance trait directly, over 88 percents secondary infection endometritis, cause aciesis or extend oestrous cycle. It becomes one thorny problem cursing cultivation of cows. At present the study was few about cow with retention of fetal membrances in China and other countries. The basic reason which influenced fetal membranes disch is maternal placenta and foetal placenta accretion, so it was extremely necessary to study placenta directly.The study purpose was to analyze the relationship about change of every index and retention of fetal membranes. It established rationale for precaution and management of retention of fetal membranes.Chose 10 cows placenta normally discard and 10 cows with retention of fetal membranes, laying for normal group and retention of fetal membranes group. Each to adopt amniotic fluid and foetal placenta, using endpoint method and utilizing semi-automatic biochemistry analyzer to detect the content of nitrogen monoxidum, the activity of nitricoxide synthase and glutathione peroxidase(GSH-Px), and total antioxidative capacity(TAC). To detect expression of inducible nitric oxide synthase(iNOS) and endothelial nitric oxide synthase(eNOS) in foetal placenta using immunohistochemistry method. Fluorescent quantitation detected the expression of iNOS and eNOS mRNA.The result indicated that NO content and NOS activity in foetal placenta and amniotic fluid in RFM group were all significantly higher than in NRFM group(P<0.05); TAC and GSH-Px activity were all significantly lower than in NRFM group(P<0.05). iNOS and eNOS proteinum were all express in trophoblastic cell of foetal placental villus, the expressed quantity of proteinum is significant deviation(P<0.05). The quantity of iNOS mRNA expression was significantly higher in RFM group than in NRFM group(P<0.05), the quantity of eNOS mRNA expression was significantly lower in RFM group than in NRFM group(P<0.05).It could be seen that above-mentioned bioactive substance in foetal placenta and amniotic fluid protured some effect for RFM, and the change tendency of propotional matter was identical in foetal placenta and amniotic fluid. So it decected the change of every bioactive substance to reflect indirectly the change in placenta, to pretest RFM. Efficiently expression of iNOS could promote production of NO, accordingly inhibit uterine contraction, and initiate inflammatory reaction, so it affected commonly separation between foetal placenta and maternal placenta. There was no capital effect about expression of eNOS for production of NO, the expression was affected by Ca2+-CaM. The relation with RFM need further study.