Animals

The experiments in this study and the care of animals complied with the Good Laboratory Practice guidelines for animal experiments defined by the Korea Testing and Research Institute (TBH-1252, 2009/08). Four-week old male SpragueDawley (SD) rats (n=25) bred in the specific pathogen-free status were purchased from Orient Bio (Seongnam-si, Gyeonggido, Korea). To reduce the influence of steroid hormone, only male SD rats were used. The rats were maintained under controlled environmental conditions (temperature: 23 ± 3 °C, relative humidity: 55±15%, and light/dark cycle of 12 h: light from 20:00 to 08:00 h) and provided with free access to appropriate food (Purina Korea Inc., Gyeonggi-do, Korea) and distilled water. After acclimatization to the light/dark cycle for one week, the rats were divided into five groups (control [corn oil], DEHP 0.75, 7.5, 15, or 150 mg/kg/day) with five rats per group.