Citation:

Franklin, J., B. Chorley, V. Moser, W. Oshiro, T. Beasley, K. McDaniel, AND D. Herr. Adult Offspring Performance in Trace Fear Conditioning after Concurrent Developmental Exposure to Variable Stress and Manganese. Developmental Neurotoxicology Society Meeting, San Diego, CA, June 23 - 26, 2019.

Impact/Purpose:

Abstract for poster presentation at the Developmental Neruotoxicology Society Meeting in San Diego CA.

Description:

This study is focused on the interaction of developmental manganese (Mn) exposure with stress on learning changes in the adult offspring of Long Evans (LE) rats. Pregnant LE rats were exposed to an unpredictable series of stressful events, which had previously been shown to increase maternal corticosterone levels. These stressors were presented daily from gestational day (GD) 13 through postnatal day (PND) 9. Groups of stressed dams and control dams were exposed to 0, 2, or 4 mg/mL of Mn in drinking water from GD 13 through PND 22. Starting at PND 97, male and female offspring were trained with a trace fear conditioning (TFC) protocol, whereby rats were exposed to a compound cue (light and tone) followed by 30 seconds (trace period) and a mild foot shock (1mA, 0.5 seconds). Five paired training sessions occurred on the training day. The following day, context and cue learning was assessed by measuring motor activity. Preliminary data suggests that all treatment groups displayed learning during context testing. No significant treatment effects were noted for stress, Mn, or concurrent exposure to both when compared to control offspring performance. On-going research with two additional cohorts will increase sample size and examine transcriptional changes in the hippocampus and amygdala of adult rats after learning the TFC task. This abstract does not necessarily reflect EPA policy.

Record Details: