Study On The Relationship Between Corticotropin-Releasing Hormone Receptor Ⅰ And Onset Of Labor

The mechanisms of onset of labor remains unclear.laboring is acomplicating physical process,which needs the preparations of materal and thematuration of fetal.The human uterus differentiates into an actively contractingupper segment and a relatively quiescent lower segment at the time oflabor.the factor involved in this anatomical functional diffentiation of theuterus remains unclear. One possible important regulating factor is CRH, ithas proved that CRH-R1 is abroadly expressed in the human reproductivetissues,including placenta,fetal membrane,decidue and myomecyte ..more andmore study shows that CRH and its receptors exerts important roles during theprocess of labor.The study included 32 patients undergoing cesarean section from May2003 to November 2004 at the department of Obstetrics and Gynecology inthe Second Clinical Hospital of Jilin University and changchun hospital ofObstetrics and Gynecology.16 cases of at laboring (group 1),which includes 8cases of preterm and 8 cases of term pregnant and 16 cases of before laboring(group 2)which includes 8 cases of postterm and 8 cases of termpregnant,myometrial samples were collected from the lower segment . Allpatients included in our study had not used any constraction-inducingmedicine like oxytocin before operation.Immunohistochemical staining forCRH-R1 were performed by SP. The staining intensity was expressed withhistological score (H –Score) and analysed with HPIAS-1000 color imaginganalysis system. SPSS statistical software was used for statistical analysis. Thesignificance of differences between individual groups was assessed witht-test ,rank sum test and so on. In the present study, we have detected CRH-R1 H-Score of group1 wasmuch higher than group2 (P<0.05), further confirms that CRH-R1 as thereceptor of CRH involved the process of initiation of parturition.On the otherhand, CRH-R1 H-Score was not significantly different between posttermpregnant and term pregnant in group 2, suggesting CRH-R1 maybe involvesthe mechanism of failure of onset of labor in postterm pregnant .furthermore,CRH-R1 H-Score was also not significantly different between pretermpregnant and term pregnant in group 1,indicates onset of labor in pretermpregnant is mediated by the combine of CRH with CRH-R1,the abnormalelevated level of CRH-R1 in preterm pregnant maybe the start-up factorinduing labor. CRH exerts its actions by means of endocrine,paracrine and autocrinecombining with its special receptors which abroadly distribute in the hunmanreproducing tissues. the potential role of CRH-R1 is much more importantamong the special receptors . The above-discussed results suggest CRH-R1 may be expected to be animportant molecular indicator in the research of onset of labor.