Inhibition of long-term potentiation in developing rat visual cortex but not hippocampus by in utero exposure to polychlorinated biphenyls.

The neurotoxic potential of polychlorinated biphenyls (PCBs) depends on the structure of the congener as well as on the age of the exposure. We exposed rats prenatally to a coplanar congener (PCB-77) or to a non-coplanar congener (PCB-47) and measured the amount of long-term potentiation (LTP) at postnatal days 11-19 in the visual cortex and hippocampus. While PCB-77 exposure affected LTP statistically significantly in cortical but not hippocampal slices, the exposure to PCB-47 was much less effective.