Manganese consumption and perinatal stress cause persistent, sex-dependent, and complex changes in attentional function in rats.
DNTS P10
Manganese consumption and perinatal stress cause persistent, sex-dependent, and complex changes on attentional function in rats
Wendy Oshiro 1, Tracey Beasley1, Kathy McDaniel1, Ginger Moser 2, David Herr1
1 US EPA, Research Triangle Park, USA. 2 Retired, US EPA, Research Triangle Park, USA
Abstract
The developmental effects of chemicals that co-occur in vulnerable populations with elevated physical and psychological stress are of increasing concern to risk assessors. In order to assess causality of these factors we developed a rodent model of co-occurring perinatal manipulations and conducted a series of behavioral assessments in male and female offspring. Manganese (Mn), a potential neurodevelopmental toxicant, was delivered in drinking water (0, 2, or 4 mg/ml Mn) of pregnant rats from gestational day (GD) 7 to postnatal day (PND) 22. A variable perinatal stress paradigm (PS) was applied to half of the animals from GD13 to PND9. Acoustic startle response (ASR) and choice reaction time (CRT) were evaluated in adults. The ASR and its habituation were unaffected by stress or Mn, whereas prepulse inhibition of the ASR yielded a significant interaction of Mn, Stress, and prepulse noise; however, contrasts were not significant. Mn reduced cued but not uncued CRT accuracy in males, and PS alone reduced accuracy in 0 mg/ml Mn-males compared to non-stress males. PS increased female movement time (MT) but not decision time on both CRT tasks. A significant interaction of PS and Mn occurred on cued MT at the 4 mg/ml dose in both sexes. These data demonstrate the ability of both PS and Mn to impair attentional function in adult animals. Furthermore, the data show evidence of PS modifying the effect of Mn on movement in both sexes. This abstract does not reflect EPA policy.