Abstract
Bisphenol A (BPA), one of the environmental endocrine disrupter, is released from polycarbonate plastics and may influence the sexual differentiation of brain function. In this study, BPA was exposed to the pregnant wister rats at a dose of 0.1ppm during the last week of prenatal period. This dosage is below the tolerable daily intake level (TDI; 50μg/kg/day). At a age of 6weeks, behavioral tests were started. The offspring were tested using an open field test, an elevated plus maze test, a passive avoidance test, and a forced swimming test. In the BPA treated group, sex differences of the number of rearing and the duration of struggling behavior were disappeared. The duration of immobility, an indication of deppressive behavior, in the forced swimming test was elongated, and the duration of staying in the open arm in the elevated plus maze test were decreased. These findings suggest that the low dose of bisphenol A during the fetal periods impair sexual differentiation of the exploratory behavior, and enhance the depressive behavior and anxiety. [Jpn J Physiol 54 Suppl:S193 (2004)]
