The Effects Of Different Time Of Mifepristone On The Morphological Change And The Expression Of ER,PR In Human Decidua And Chorion Tissue In Early Pregnancy

Objective: Medical abortion is a non-surgical option for women who elect to terminate a pregnancy. The popular method is 150 mg or 200 mg oral mifepristone followed by 600μg oral misopristol, which the total rate of abortion is approximately 90%. But this method is a long period option, if the time interval between mifepristone and misopristol can be shortened, it will benefit for the patient and improve the acceptability of medical abortion to women.Mifepristone, as a antiprogestin, is used to terminate pregnancy, and as such is commercially available in many countries. Mifepristone take the action of intercepting progestin by the combination with PR, causing the decidua and chorion to degenerate and necrosis, then inducing abortion. The mechanism of action of mifepristone relate to many aspects. The influence of mifepristone to ER,PR in decidua and chorion tissue is very important.The objective of this sturdy is by light microscope, electron microscope and immunohistochemistry technique, to observe the morphological change and the expression of ER,PR in decidua and chorion tissue when the time from oral mifepristone is 12 hours,24 hours and 48 hours, clear-cut the concrete action of mifepristone on ER,PR, analyze the effects of different time of mifepristone on the decidua and chorion tissue in early pregnancy, investigate the feasibility of shortening the time of mifepristone and provide the theory basis for simplifying the medical abortion plan in clinical treatment.Method:1 All the specimens were collected from the women who desire to terminate the early pregnancy in the department of gynecology and obstetrics of Hebei people hospital from March 2007 to May 2007. The eighty women were divided into four groups : control group, 12 hours group, 24 hours group, 48 hours group. The decidua and chorion tissue after uterine aspiration have been collected.2 Observe the morphological change of decidua and chorion tissue by light microscope and transmission electron microscope. Detect the expression of ER,PR in decidua and chorion tissue by immunohistochemistry technique and computer image analysis system.3 Analyze the data with SPSS13.0.Results:1 Light microscope showed:The decidua tissue of control group contain decidual cell and granular cell. The structure is complete and the rank is compact. The 12 hours group showed: the decidual cell turn to degenerate and necrosis, interstitial edema, blood capillary expand and engorge, inflammatory cell infiltrate and the cell bleed. The morphological change of 24 hours group and 48 hours group is basically alike to the 12 hours group. The tissue necrosis of 48 hours group is further serious.The structure of chorion trophoblastic cell of control group is clear, which the outer layer is syneytiotrophoblast and the inner layer is langhans cell. The 12 hours group showed: the cell degenerate, necrosis, even amotic, the inflammatory cell infiltrate, the chorion interstitial edema, the blood siltation and the fibrin deposition. The change of 24 hours group and 48 hours group is basically alike to the 12 hours group.2 Electron microscope showed:The volume of decidual cell of control group is large and the cell organ is abundant, while the volume of granular cell is relative small which contained affluent electron-dense granum. The collagen fibers among cells is abundant, and they line up in order. The 12 hours group showed: the decidual cell is full of many saccular dilatation RER, the bulk cristae of mitochondrium is mixed with membrane which turned to unclear or deletion, the amount of electron-dense granum reduce or disappear, the collagen fibers disorder, break, even disintegrate. The change of 24 hours group and 48 hours group is basically near to the 12 hours group.The surface of syneytiotrophoblast of control group has many microvilli. The 12 hours group showed: the quantity of microvilli decreased, the cell-substance dropsy, the langhans cell flatten and shrink, the outline of cell is unclear, the conjunction between syneytiotrophoblast and langhans cell turn to chalasis, the cell spaces widen. The change of 24 hours group and 48 hours group is basically near to the 12 hours group.3 The expression of ER in decidua and chorion tissueIn decidua tissue of control group, the expression of ER locate in the majority of decidual cell and the minority of glandular epithelium cell. The masculine grana is more in the nucleus, and endochylema has a small quantity. The expression of ER in 12 hours group, 24 hours group and 48 hours group is significant lower than control group(P<0.05), and there is no difference among the there group(P>0.05).In chorion tissue of control group, the expression of ER is in the nucleus and intracytoplasm of the chorion cell. The expression of ER in 12 hours group, 24 hours group and 48 hours group is significant lower than control group(P<0.05), and there is no difference among the there group(P>0.05).4 The expression of PR in decidua and chorion tissue In decidua tissue of control group, the expression of PR is in the nucleus and intracytoplasm of the majority of decidual cell and the minority of glandular epithelium cell. The PR expression of other groups is significant lower than control group(P<0.05), and there is no difference among the there group(P>0.05).The expression of PR is positive in the nucleus and intracytoplasm of the chorion cell of control group. The PR expression of other groups is significant lower than control group(P<0.05), and there is no difference among the there group(P>0.05).Conclusions:1 Mifepristone rivalry the progestational action by the combination with PR, making the decidua and chorion tissue degenerate and necrosis, then inducing abortion. Through these mifepristone can achieve the purpose of terminating pregnancy.2 The normal decidua and chorion tissue of early pregnancy have complete structure. It will change 12 hours after oral mifepristone. The decidua and chorion cell turned to dropsy, degenerate and necrosis, which exist to 48 hours after oral mifepristone.3 ER and PR express in the normal decidua and chorion tissue of early pregnancy. The expression has already been inhibited 12 hours after oral mifepristone. The dynamic balance between ER and PR has been destroyed and the pregnancy is hard to maintain. This action will last to 48 hours after oral mifepristone.4 The action to chorion of mifepristone has indirect effect arising from the degeneration of decidua. And it can directly repress the chorion nutrient cell, promote the necrosis and amotic.5 The result of our research indicate the plan that shorten the time between mifepristone and misopristol to 12 hours in medical abortion is feasible. If it can be confirmed by many clinical experiment and spread to clinical treatment, the medical abortion will have a fine perspective.