Objective: To investigate the expression of vascular endothelial growth factor (VEGF) and its receptor, kinase insert domain-containing receptor(KDR) and microvessel density (MVD) in endometrium from women wearing fixed copper-intrauterine contraceptive device (IUD, FCu-IUD) or fixed indomethacin-releasing copper-IUD (FICu-IUD).
Methods: Twenty healthy women were divided into two study groups: 10 cases wearing the FCu-IUD (FCu-IUD group), 10 cases wearing the FICu-IUD (FICu-IUD group). Immunohistochemical technique was used to determine the expression of VEGF and KDR in endometrium, and the microvessel density (MVD) was counted. The expression of VEGF mRNA was determined by in situ-hybridization.
Results: Before insertion of FCu-IUD, the expression of VEGF and KDR proteins was 0.357 +/- 0.032 and 0.215 +/- 0.029 respectively. After insertion of FCu-IUD, the expression of VEGF and KDR proteins was 0.568 +/- 0.027 and 0.244 +/- 0.022 respectively, significantly higher than before insertion (P < 0.05). The expression of VEGF mRNA was 0.359 +/- 0.022 before insertion of FCu-IUD, after insertion of FCu-IUD, the expression of VEGF mRNA was 0.425 +/- 0.019 (P < 0.05). There were no significant changes in the level of VEGF protein and mRNA, as well as KDR in endometrium before and after insertion of FICu-IUD. Compared with before insertion of FCu-IUD 15.4 +/- 2.8, a significant increase in MVD was observed after insertion of FCu-IUD 19.8 +/- 4.8, and the expression of VEGF protein was positively correlated with MVD (r = 0.847, P < 0.01). MVD counts were not different significantly before and after insertion of FICu-IUD.
Conclusions: FCu-IUD can enhance the expression of VEGF and KDR in the endometrium. FICu-IUD can inhibit the activity of VEGF and KDR by releasing indomethacin. VEGF and KDR may be related to the structural and functional changes of microvessels in endometrium after insertion of FCu-IUD or FICu-IUD.