Hippocampal long-term potentiation (LTP) is reduced by a coplanar PCB congener.
Neurotoxicity of polychlorinated biphenyls (PCBs) is usually ascribed to the ortho-substituted congeners. We have examined the effects of acute perfusion of 3,3',4,4'-tetrachlorobiphenyl (PCB 77), a coplanar, dioxin-like congener, on long-term potentiation (LTP) in the Schaffer collateral-CA1 and the mossy fiber-CA3 pathways in mouse hippocampus. LTP in both pathways was blocked by PCB 77, with a threshold effect at a concentration of 1 microM. LTP is a useful model of learning and memory function in which a patterned stimulation of an afferent pathway produces a persistent increase in the efficacy of synaptic transmission. LTP is reduced by PCB mixtures and ortho-substituted congeners at concentrations comparable to those studied here. These observations provide evidence in support of the hypothesis that dioxin-like and non-dioxin-like PCB congeners are equally potent in causing the cognitive decrements seen in children exposed prenatally to PCBs.
School of Public Health, University at Albany, One University Place, Rensselaer, NY 12144-3456, USA.
Mete
M
Ozcan
Bayram
B
Yilmaz
W Michael
WM
King
David O
DO
Carpenter
D000818:Animals; D004305:Dose-Response Relationship, Drug; D006624:Hippocampus / Q000187:drug effects* / Q000502:physiology; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000187:drug effects* / Q000502:physiology; D051379:Mice; D008813:Mice, Inbred ICR; D011078:Polychlorinated Biphenyls / Q000737:chemistry* / Q000494:pharmacology*
D011078:Polychlorinated Biphenyls