Correlative investigation of copper/low-density polyethylene nanocomposite on the endometrial angiogenesis in rats

The purpose of this study was to investigate the effects of copper/low-density polyethylene nanocomposite (nano-Cu/LDPE) on the endometrial angiogenesis in rats, and 100 sexual mature female SD rats were randomly divided into five groups: sham-operation groups (SO group, n = 20), bulk copper groups (Cu group, n = 20), LDPE groups (n = 20), nano-Cu/LDPE groups I (n = 20) and II (n = 20). The levels of angiopoietin-2 (Ang-2), its receptor (Tie-2) and CD34 of the rats' endometria in each group were examined by using the S-P method of the immunohistochemistry 30 and 180 days after insertion, respectively. Compared with those in the SO group, the expression of Ang-2 and Tie-2 in all the experimental groups was obviously increased 30 days after insertion, and these parameters in nano-Cu/LDPE groups, except for Ang-2 level in nano-Cu/LDPE group II, were significantly lower in comparison with those in Cu group (P < 0.05). On the 180th day after insertion, Ang-2 and Tie-2 levels were still higher in Cu group and LDPE group, but there was no difference of Ang-2 and Tie-2 levels between nano-Cu/LDPE groups and the SO group (P > 0.05). Compared with those in the SO group, the significant increases in microvessel density (MVD) were observed on the 30th and the 180th day after the insertion of the bulk copper (P < 0.05). There was no significant difference in MVD counts before and after the insertion of nano-Cu/LDPE (P > 0.05). The results show that Nano-Cu/LDPE have slighter influence on the endometrial angiogenesis than bulk copper.