Reproductive abnormalities in adult male mice following preimplantation exposures to estradiol or pesticide methoxychlor

Adult females of ICR strain of mice were bred, separated into different experimental groups, and treated as follows. On Days 2-4 of pregnancy, the mice received daily subcutaneous injections of either 0.05 ml sesame oil (vehicle) or same volume of 5.0 mg of purified methoxychlor (MXC) suspended in the vehicle. Another group received a single subcutaneous injection of 1.0 μg of estradiol-17β (E) on Day 2 of pregnancy only. Male offspring were tested at 3 and 6 months of age. At 3 months, E or MXC did not alter the weights of seminal vesicles, preputial glands, or testes, although after exposure for 30 min to a female in estrus behind a partition, testosterone levels were significantly reduced in treated males in comparison to control males exposed to the same partition test. At 6 months, the preputial glands and testes weight remained unchanged, while the seminal vesicles were significantly heavier in E- and MXC-treated males. Same partition tests again revealed that in E and MXC groups, testosterone levels remained significantly lower in comparison to control males. MXC or E exposures during preimplantation appear to induce long-term effects on the sexual development in 3 and 6 month-old-males by compromising their sexual arousal and altering seminal vesicles weights in the older group.