The antifertility effectiveness of copper/low-density polyethylene nanocomposite and its influence on the endometrial environment in rats☆

Abstract Purpose The study was conducted to investigate the antifertility effectiveness of copper/low-density polyethylene nanocomposite (nano-Cu/LDPE) and its influence on the endometrial environment in rats. Methods One hundred and seventy sexually mature female Sprague���Dawley (SD) rats were randomly divided into five groups: sham-operated control group (SO group, n =10), bulk copper group (Cu group, n =40), LDPE group ( n =40), and nano-Cu/LDPE groups I ( n =40) and II ( n =40). Twenty rats in each group except for the SO group were mated with male rats of proven fertility, from 30 days after insertion, and the antifertility rates (ATs) were observed at Day 11 of pregnancy. The concentrations of prostaglandin E 2 (PGE 2 ) and tissue plasminogen activator (tPA) in the endometrium of the remaining rats in each group were measured by using ELISA at the 30th and 60th day after insertion, respectively. Results ATs in the Cu group and nano-Cu/LDPE groups I and II (100%) were significantly higher than those in the LDPE group (p 2 and tPA in all experimental groups except for PGE 2 levels in the LDPE group were significantly increased at Day 30 after insertion, and these parameters in the nano-Cu/LDPE groups were significantly lower than in the Cu group (p 2 levels in all groups except for the Cu group. Conclusion Nano-Cu/LDPE exhibits satisfactory contraceptive efficacy with less influence on the endometrium PGE 2 and tPA levels.