Expression And Significance Of Cx43 And Bax,bcl-2 In Fetal Memberane Of Premature Rupture Of Human Fetal Memberane

Rupture of human fetal memberane before in labor is known as the premature rupture of memberane(PROM),divided into preterm premature rupture of memberane(pPROM) and term premature rupture of memberane(tPROM) according to gestational age(37weeks).PROM can induce premature birth,infection,prolapse of umbilical cord and so on,raise case fatality ratio of mother and fetus,neonate during perinatal period.PROM is one of complications threatening health of mother,fetus and neonate.Now the certain etiopathogenisis and mechanism of PROM is not clear-cut yet,this brings about difficulty for preventing PROM.For the past few years, studies of the relationship between cytokines,apoptosis,enzymes and PROM have reached level of molecular biology,but the studies about the growth development of fetal memberane is less.Gap junctions is one of communication ways between cells,comprised of connexin(Cx).Gap junctions play regulatory role for cellular increment,cell differentiation,apoptosis,maintaining stable state of internal environment,metabolism and growth and development and so on.Cx is foundation of maintaining normal formation and functions of organism.Cx have many isoforms,the expression of Cx43 is extensive.Studies presume correlation between apoptosis and PROM,In B-cell lymphoma/leukemia family,Bcl-2 protein can inhibit apoptosis,while Bax protein can promote apoptosis,whether they play a role in the regulation of apoptosis in fetal memberane has different reviews in literatures.ObjectiveTo detect the expression of connexin 43,Bax and Bcl-2 in fetal memberane of premature rupture of human fetal memberane(PROM) and non-PROM with immunohistochemistry(PV-9000),and to analyze their roles and correlations in the etiology and pathogenesis of PROM;To investigate the relationship between the normal and abnormal expression of Cx43 and the growth development of fetal membranes,to further examine the roles of Bax and Bcl-2 in the pathogenesis of PROM;To deduce the different etiology and pathogenesis of pPROM and tPROM by contrastive analysis.Provid theoretically evidences for Preventing PROM.MethodsFetal memberane from 60 cesarean section deliveries were included in the study. Thirty of 60 deliveries had PROM,and divided into preterm premature rupture of memberane(pPROM)(n=15) and term premature rupture of memberane(tPROM) (n=15) according to gestational age.Thirty non-PROM deliveries served as control group.All cases had no other complications of pregnancy,and had no regular uterus contraction.All the fetal memberane was immediately taken from the site which was 2cm×2cm and 1cm far away from the artificial rupture site of the supracervical membranes within 10 mintues after cesarean section.The samples which had been cleaned by normal sodium were fixed in buffered formalin,followed by routine paraffin embeding,cutting(3μm).The diagnostic criteria of PROM is according to the first edition of Obstetrics and Gynecology which the chief editor is Feng youji and Shen keng,published by the public health people publishing company in Beijing.Staining with hematoxylin and eosin(HE) for morphology observation and detecting the expression levels of Cx43,Bax and Bcl-2 proteins in tissue samples with immunohistochemistry.PV immunohistoche-mistrymasculine cell diagnosed standard is like that:endochylema,plasmalemma and nucelus was presented buffy or brown. Cx43,Bax and Bcl-2 in fetal memberane were collected by computer image analysis system of Biosens Digital Imaging System and analyzed by the software of leica Qwin.Statistical analysis was performed with SPSS10.0 software,numerical data was demonstrated as mean±standard deviation.Group comparisons were using analysis of variance,the least significant difference(LSD) and linear correlation analysis was used to determine the relationship between them.Statistically significant level was considered as "a=0.05".Results1.Morphology observation of fetal membranes by HE staining:In the PROM group,the stucture of fetal memberane presented obviously changes as follow, amnion and chorion were not integrality and observed delaminately,amnion epithelial cell and the basement membranes presented uncontinuity and disorder,fibrillar collagen and amnion extracellular matrix(ECM) were also in disordered and dramatic loss state.But the control group had normal amnion and chorion stucture.2.The expression and fixing of Cx43,Bax and Bcl-2 in fetal memberane were detected by PV immunohistochemistry method:Expression of Cx43,Bax and Bcl-2 were detected in the fetal memberane of all groups.The masccline expression of Cx43 was major fixed in the plasmalemma,endochylema and nucleus of chorion trophocyte and less in amnion epithelial cell;Bax expression was in the endochylema of chorion trophocyte and less in amnion epithelial cell;Bcl-2 was mainly expressed in the plasmalemma and endochylema of chorion trophocyte.3.The expression levels of Cx43,Bax and Bcl-2 in the fetal memberane of all groups:①In tPROM group,expression of Cx43 and Bcl-2 were obviously lower than the expression in control group(P＜0.01);Bax expression was higher than in control group(P＜0.05).②In pPROM group,expression of Cx43 was lower than the expression in tPROM group(P＜0.01);But expression of Bcl-2 and Bax were not significant differences between pPROM group and tPROM group(P＞0.05).4.The correlation of Cx43,Bax and Bcl-2 in PROM group:In PROM group, negative correlation was found between Cx43 and Bax expression(r=-0.309, P=-0.016);But no correlation was found between Cx43 and Bcl-2 expression(r=-0.199,P=0.145).Conclusion1.Fetal Membranes in patients of PROM,low expression of Cx43-mediated membrane organization dysplasia,the high expression of Bax and low expression Bcl-2-mediated apoptosis may be related to the occurrence of PROM;2.Fetal Membranes in patients of PROM,correlation of Cx43 and Bax prompts the two may play the synergy during the occurrence of PROM;3.Occurrence of pPROM may be prone to developmental anomaly of fetal membranes;The occurrence of tPROM may be related to the degeneration of fetal membranes and excessive apoptosis of cell;To prompt that pPROM and tPROM had different etiology and pathogenesis.