Maternal exposure to polychlorinated biphenyls inhibits long-term potentiation in the visual cortex of adult rats

Rats were exposed prenatally to the coplanar congener 3,3',4,4'-tetrachlorobiphenyl (TCB). The amount of long-term potentiation (LTP) was measured in slices from the visual cortex and hippocampus of the adult males as well as of controls. While in the cortical slices from the controls a stable LTP could be induced, LTP was inhibited in the TCB-exposed rats. In hippocampal slices, the amount of LTP was not significantly different between the two groups. Our results suggest that the visual cortex of adult animals is functionally altered by TCB if the exposure takes place during embryonic development.