Prenatal arsenic exposure alters the programming of the glucocorticoid signaling system during embryonic development.

The glucocorticoid system, which plays a critical role in a host of cellular functions including mood disorders and learning and memory, has been reported to be disrupted by arsenic. In previous work we have developed and characterized a prenatal moderate arsenic exposure (50ppb) model and identified several deficits in learning and memory and mood disorders, as well as alterations within the glucocorticoid receptor signaling system in the adolescent mouse. In these present studies we assessed the effects of arsenic on the glucocorticoid receptor (GR) pathway in both the placenta and the fetal brain in response at two critical periods, embryonic days 14 and 18.

Fluoxetine treatment ameliorates depression induced by perinatal arsenic exposure via a neurogenic mechanism.

Several epidemiological studies have reported an association between arsenic exposure and increased rates of psychiatric disorders, including depression, in exposed populations. We have previously demonstrated that developmental exposure to low amounts of arsenic induces depression in adulthood along with several morphological and molecular aberrations, particularly associated with the hippocampus and the hypothalamic-pituitary-adrenal (HPA) axis. The extent and potential reversibility of this toxin-induced damage has not been characterized to date.