Experimental Study Of MMP-9、TIMP-1 In The Pathogenesis Of Amniotic Fluid Embolism In Rats

Objective:This topic is to simulate the process of amniotic fluid embolism in pregnant rats,To investigate the expression level change of MMP-9 and TIMP-1 in serum and lung tissue of amniotic fluid embolism(AFE)rats, and to explore the relations with amniotic fluid embolism, to provide a theoretical basis for clinical diagnosis and forensic work.Methods: The pregnancy SD rats were randomly divided into control group(NS, n=10), amniotic fluid group(AF, n=10),the mixture of amniotic fluid meconium group(MAF, n=10).Modified methods was used to form amniotic fluid embolism model.After the anesthetic works, blood samples were drawn from orbit before the surgery, separation of abdominal aorta after hysterectomy and take blood samples,then to collect amniotic fluid, meconium with clean EP, standby.The lung tissues were collected for HE staining, CK16,MMP-9 and TIMP-1immunohistochemistry.The MMP-9 and TIMP-1 in the bloods amniotic fluid, certain percentage of meconium amniotic fluid detection method is using the enzyme-linked immunosorbent assay(ELISA). All data were analyzed by using SPSS17.0 statistical software and were expressed as median standard error,α < 0.05 was statistically significant.T test in the group,LSD-t between the group covariance,α < 0.05 was statistically significant.Results: 1.Clinical manifestations: in the group NS was injected with saline after transient heart rate, after the bleeding puncture was 1~3min;AFgroup respiratory rate, heart rate becomes shallow, after the first speed up slow down, after the puncture bleeding time was 3~6min, convulsions, incontinence symptoms during the observation period; MAF group of similar symptoms was earlier and heavier, have obvious abnormality of blood coagulation, hemostasis time. After wearing 10~15min. 2.Pathological examination:Maceoscpic observation NS group with dark red in lung tissue; AF group in Pale red and MAF group was the most obvious.The results of HE staining showed that there was no no significant change in the NS group;there was varying degrees of pulmonary edema, inflammatory cell infiltration, squamous epithelium, mucus and other amniotic fluid components in the pulmonary vascular in AF group and MAF group. 3.The results of CK16 Immunohistochemistry staining showed that there was no no significant change in the NS group;there was squamous epithelium and other amniotic fluid components in the pulmonary vascular in AF group and MAF group. 4.The concentration of MMP-9 and TIMP-1in the amniotic fluid and meconium by ELISA method to detect the result show: MMP-9 concentration in amniotic fluid is about 3.105±0.345μg/L,in the meconium amniotic fluid liquid proportion is about 6.125±0.543μg/L.MMP-9 concentration in amniotic fluid is about 99.105 ±3.145pg/m L, in the meconium amniotic fluid liquid proportion is about 55.335 ±2.543pg/m L. 5.Three groups pro-experiment and post-experiment MMP-9 concentration by ELISA method to detect the result show: NS group before and after the experiment and There was no statistical significance between the three groups before the experiment(p>0.05),The AF group and MAF group were statistically significant(p<0.05) before and after the experiment,Group MAF and group NS, group AF, group NS and group AF were statistically significant(p<0.05). 6.Three groups pro-experiment and post-experiment TIMP-1 concentration by ELISA method to detect the result show: NS group before and after the experiment and There was no statistical significance between the three groups before the experiment(p>0.05),The AF group and MAF group were statistically significant(p<0.05) before and after the experiment,Group MAF and group NS, group AF, group NS and group AF were statistically significant(p<0.05). 7.Three groups pro-experiment and post-experiment MMP-9/TIMP-1 of dynamic balanced condition by ELISA method to detect the result show: the NS group were 5.856±0.105 and 6.246±0.135;the AF group were 5.759±0.128 and 7.278±0.095; the MAF group were 5.657±0.123 and 10.552±0.996. 8.MMP-9IHC and TIMP-1IHC examination: In the NS group, the expression of MMP-9 in the alveolar cells, plasma cells and central granule cells was small and the color was light, while TIMP-1 was expressed in a large amount, and the color was deep;In AF group and MAF group, the expression of MMP-9 was observed in the alveolar cells, plasma cells and central granule cells, and the color was deeper, and the MAF group was more obvious;As well as see TIMP-1 a certain amount of expression, the color is shallow.Conclusion:1.The establishment of amniotic fluid embolism model was successfully established by HE staining and IHC method. 2.The abnormal of MMP-9 and TIMP-1 may be involved in the process of lung injury induced by amniotic fluid embolism, and aggravate the occurrence and development of lung injury. 3.MMP-9/TIMP-1 imbalance may be involved in the pathophysiology of amniotic fluid embolism.