The Effects Of Nano-Cu/LDPE-IUD On Rabbit Uterine Internal Environment

Intrauterine Device (IUD) is the most commonly used contraceptive method in the world, because of its prolonged action, safety, economy, convenience and good recoverability. But the majority of them are made of bulk-copper. In the process of the corrosion of bulk-copper-IUD placed in the uterine cavity, the burst release of Cu2+ and excess oxidate products can be found, which were the main facts that caused abnormal uterine bleeding and pain, so how to avoid the burst release of Cu2+ by regulating the Cu2+ release in the uterus which is the core of IUD material breakthrough.Nano-Cu/LDPE-IUD is made of Nano-Cu/LDPE material. This material combines pure Nano-Cu particle and low density polyethylene (LDPE). The Nano-Cu/LDPE-IUD uses LDPE as its carrier so as to utilize Nano-Cu particle's high catalysis and high selectivity and produce prolonged consistency through the stabilization of LDPE. Nano-Cu/LDPE-IUD can regulate the release of Cu2+ in the uterine cavity so as to reduce the burst release of Cu2+ and stabilize the contents of Cu2+ in the uterine fluid.The researches observed the different uterine internal environment changes of female rabbit after insertion of different IUDs from four parts as following: Part I The Impact of Nano-Cu/LDPE-IUD on Ultrastructure of Rabbit EndometriumObjective: To detect the influence of different types of IUD on the endometrial ultrastructure of rabbits and to evaluate the foreign body reaction of Nano-Cu/LDPE-IUD, then analyze their impact level.Methods: Forty normal sexual mature rabbits who had previously pregnant history, weight are 2.0~2.5kg, which were divided into five groups randomly, including blank control group, biomaterial group, Cu-IUD group, low dose releasing Nano-Cu/LDPE-IUD group(5~10μg/220mm2) and high dose releasing Nano-Cu/LDPE-IUD group(10~20μg/220mm2). After insertion of different IUDs for 56 and 72 days, scanning and transmission electron microscope were used to observe the ultrastructural changes in each group after insertion of IUD.Results: Irregular pattern of microvilli of epithelial cells, big vacuole and swollen mitochondria cristae in cytoplasm, increased microfilaments and broadened cell-cell junction were observed in Cu-IUD group. The morphological changes of Nano-Cu/LDPE-IUD groups were characterized by shed microvilli of epithelium cells, normal nuclear structure and shape of epithelium cells, slight swollen mitochondria cristae in cytoplasm and normal cell-cell junction.Conclusion: Compared with Cu-IUD, Nano-Cu/LDPE-IUD can lessen the stimulation on the uterus.Part II The Impact of Nano-Cu/LDPE-IUD on the Level of t-PA,PAF,PGE2 in the Endometrium Serous Fluids of RabbitObjective: To detect the impacts of different types of IUDs on the level of t-PA, PAF, PGE2 in the endometrium serous fluids of rabbits. Methods: The animals and groups were the same with the first part. The enzyme linked immunosorbent assay (ELISA) was performed to estimate the level of t-PA, PAF, PGE2 in the endometrium serous fluids of IUD-inserted rabbits.Results: Compared with Cu-IUD group, the level of t-PA and PGE2 in the endometrium serous fluids of Nano-Cu/LDPE-IUD group were significantly decreased.Conclusion: The results indicated that Nano-Cu/LDPE-IUD could depress the rising level of t-PA and PGE2 caused by Cu-IUD, it can caused gentler stimulation on endometrium than Cu-IUD.Part III The Impact of Nano-Cu/LDPE-IUD on the Expression Level of PAI-1, SP and SP-R in the Endometrium of RabbitObjective: To detect the expression level of PAI-1, SP and SP-R in the endometrium of Rabbit, and to analyze the mechanism of lighter foreign body reaction caused by Nano-Cu/LDPE-IUD.Methods: The animals and groups were the same with the first part. The immunohistochemical (S-P method) was used to detect the expression level of PAI-1, SP and SP-R in the endometrium of rabbits.Results: PAI-1 was mainly expressed around the endometrial blood vessels, in the cytoplasm of smooth muscle cells and some epithelioglandular cells. The expression level of PAI-1 in the endometrium of Nano-Cu/LDPE-IUD group was significantly higher than that of Cu-IUD group. SP and SP-R were mainly expressed around endometrial blood vessels, some in the cytoplasm of smooth muscle cells and stromal cells. The expression level of SP and SP-R in the endometrium of Nano-Cu/LDPE-IUD group was significantly lower than that of Cu-IUD group.Conclusion: Compared with Cu-IUD, Nano-Cu/LDPE-IUD can raise the expression level of PAI-1, and lower the expression level of SP and SP-R in the endometrium.Part IV The Detection of Expression Level of MMP2 mRNA and Labeled Molecule of Apoptosis After Rabbit Endometrium Cell Cultured in Vitro with Cu2+ FluidsObjective: To detect the changes of apoptotic index and expression level of MMP2 mRNA in the endometrium cells of rabbits which cultured with different Cu2+ concentration at different time, then analyze their relationship.Methods: Culture in vitro of rabbits endometrium cell was successed, give the intervention of Cu2+ fluids, the final concentration of the Cu2+ were 8×10-5M,1.6×10-4M,3.2×10-4M, set the control group. Collected the cell discus after 12h, 24h, 48h. In situ hybridization method was used to detect the impression level of MMP2 mRNA, and the apoptotic index of the culture cells was investigated.Results: MMP2 mRNA was mainly expressed in kytoplasm and set up with time and Cu2+ concentration. Apoptosis existed in every groups, apoptotic index between the groups was no different.Conclusion: The expression level of MMP2 mRNA was enhanced with the Cu2+ concentration and time, which can provide evidence that the burst release of Cu2+ in uterus after insertion of Cu-IUD could cause uterus abnormal bleeding and pain. The side effects of insertting Cu-IUD were not the results of apoptosis.