Influence of maternal restraint stress on the long-lasting effects induced by prenatal exposure to perfluorooctane sulfonate (PFOS) in mice.

The behavioral effects of concurrent maternal exposure to restraint stress and perfluorooctane sulfonate (PFOS) were assessed in the offspring of mice at 3 months of age. Plug positive females were divided into two groups. Animals were given by gavage 0 and 6mg PFOS/kg/day on gestation days 12-18. One-half of the animals in each group were subjected to restraint stress (30min/session, three sessions per day) during the same period. At 3 months, mice were evaluated for general activity in an open-field, and for learning and memory in a water maze task. The group prenatally exposed to PFOS and restraint presented a reduced mobility in the open-field. In the water maze, an interaction between sex and restraint was observed. Delayed task learning was also detected in females prenatally exposed to PFOS and restraint. An overall effect of restraint was observed in mice on retention of the task, suggesting a better retention in restrained animals. On the other hand, corticosterone levels were lower in animals prenatally subjected to restraint stress. The current results suggest interactive effects between PFOS and maternal stress.