The Effect Of Intrauterine Device On Myoelectricity In Uterine And Endometrial Receptivity

[Objective]In this study, through the three sizes of three-dimensional IUD with memory alloy in female rabbits in utero to establish New Zealand rabbit model, to observe the contraceptive effect.The electrophysiology, morphology and other advanced technology will be performed. Through the determination of uterine myoelectricity, Hematoxylin-Eosin Staining and ELISA to detect the activity rules of uterine myoelectricity, myoelectricity different on three sizes of IUD, the rules of specific IUD peak and endometrial receptivity changes. To discuss the correlation between experimental results and contraception.[Material and Methods]1.Experimental animals and groups:adult female New Zealand rabbit24, about10-12months, weighing2.30-2.50kg,were purchased from the Animal Experimental Center, The center for disease control and prevention of Shan Dong,and were randomly divided into4groups, the order was as follows:﹕ham operation group;②the standard IUD group(consistent with the length of uterus);③1/2IUD group(half of the length of standard uterus);④1/3IUD group(third of the length of standard uterus),6rabbits in each group.2. Records of weight of the rats:The above rats were weekly weighed and recorded.2.Measurement record of uterine electromyographic:detailed observation of the frequency of the waveform and the peak, respectively to observe the normal time for2h;4h after injection of oxytocin and8h after injection of progesterone. Respectively to observe electromyography on7d,14d,30d and60d after placing IUD..Observe pregnancy rate of different specifications of IUD.3.Venous blood was collected and ET-1, vWF, vWFpp were determined by ELISA. 4.Hematoxylin-Eosin Staining of full-thickness tissue of uterus wall(direct contact with IUD), full-thickness tissue of uterus wall(next to IUD) and full-thickness tissue of uterus wall(without placing IUD):10%formalin fixed, conventionally paraffin embedded, cut into slice, xylene dewaxed, hydrated at all levels by ethanol, haematoxylin stained2minutes, hydrochloric acid alcohol differentiated15s, eosin and alcohol stained2-5minutes, conventionally dehydrated and transparent, sealed, then endothelial morphological change was observed.[Results]1. Each group uterine myoelectricity change rule and the rule of specific IUD peak1.1Control and not placing IUD side uterine emg is spontaneous, rhythmic static dynamic composite wave duster based graphics, the frequency of the peak potential for an average of682times per hour,190μv,uterine movement rate(MR)7.3%. After placing IUD,utering emg appear distinctive IUD peak,which is hihg flat and long.1.2Oxytocin excitation frequency is up to1698times per hour, maintain an hour, the fundamental wave duster activity becomes a single wave plexus, MR=8.2%(P<0.05).1.3Progesterone in basic wave plexus, first inhibition after excitement of a two-way effect,inhibition of about four hours later, and then make its amplitude present987μv and frequency excitation (2623times/h), MR=71.9%(P<0.01). Statistical analysis of testing results is to the percentage different.1.4After placing IUD, animal mating, no pregnancy.2Compared with the normal control group, after placing IUD, rabbit plasma contents of ET-1, vWF, vWFpp levels were significantly elevated, statistically significant difference (P<0.05, P<0.01).3Endometrial morphological change:3.1Macroscopic observation:Take the uterus tissue and cervical tissue of New Zealand rabbits to find abnormal obviously. Open the uterus of rabbit to find that all speciments at placing IUD has the pressure in endometrium. There is visible exudate in intrauterine in placing IUD. With the increase of IUD placement time, exudate reduced, later,there is basically no exudate in uterine cavity. The endometrium beside the IUD and distal tissue have no abnormal change. No obvious pathologic change was found in the cervix.3.2Light microscopy observation:3.2.1sham-operation control group:Under light microscopy, from inner to outer, uterine tissue is divided into mucosa tissue, submucosal tissue,muscularis tissue and serosa layer. Mucosa tissue and submucosal tissue show many fold to the uterine cavity. Glandular epithelium is simple cuboidal, without hyperplasia. There is no exudation and inflammatory cells infiltration in uterine cavity. Mucous epithelium is simple columnar epithelium, submucosal is rich in capillaries, visible red blood cells, interstitial edema, basement membrane integrity, for the muscularis and serosa outside its organization.3.2.2The experimental group:in direct compression area of IUD, uterine endometrium have varying degrees of depression, uterine cavity expansion, mucosal layer thinning, mucosal fold decrease. No obvious difference of three groups of compression degree, each time difference is not obvious. Part of three groups and various periods of rabbits, small blood vessels in uterine wall show expansion and hyperemia, differences between the three groups is not obvious. Groups in different periods, as time goes on, small blood vessels in submucosal angiectasis hyperemia ease. Local endometrial appear different degree of pseudostratified columnar epithelial hyperplasia, endometrial exudative inflammation, local exudate, include macrophage%plasma cell and lymphocyte. As time goes on, local inflammation ease, exudate reduce and gradually disappear.3.2.3Not compression zone:not compression zone is the endometrium which is not contact IUD, including uterus tissue beside the IUD and on the other side. Postoperative period, three placing IUD groups, the region did not show uterine lesions, show the similar image to the control of the uterus organization.[Conclusions] 1.As a foreign body, IUD to endometrial continuing oppression and stimulation, led to intima morphological change:mucosal layer thinning, gland hyperplasia, small angiectasis hyperemia. It shows that Uterine cavity memory alloy three-dimensional IUD, can change endometrium morphology to interference with endometrial receptive to achieve the result of contraception.2.IUD can thrill uterus to enhance uterine contraction, appear distinctive IUD peak. After the removal of IUD, IUD peak disappeared. Oxytocin made a short-acting stimulation to experimental animals. Progesterone made a long-acting and bidirectional stimulation:first curb and then excite. Experimental animals mated. We found no pregnancy. It shows memory alloy three-dimensional IUD interfere with the normal uterine myoelectricity to achieve the result of contraception.3.After placing IUD, plasma ICAM-1、vWF、vWFpp content increased significantly, showed that endothelial cell function influenced by IUD, endothelial cell activation increased, shows that IUD can promote endothelial cell activation, secretion various of divisors, change the receptivity of endometrium to influence implantation of germ cell.