Effects of lead on long-term potentiation in hippocampal CA3 vary with age.
The effects of lead on long-term potentiation (LTP) in the hippocampal area CA3 were different in 30-day (P30) and 60-day-old (P60) rats upon either acute perfusion of lead to the isolated brain slice from controls or when recorded from slices from rats after chronic developmental exposure to lead. Lead caused a significant inhibition of LTP in 30-day CA3, and a significant potentiation in 60-day CA3 with either exposure paradigm. Consistent with the effects on LTP, lead inhibits phorbol ester-induced synaptic potentiation in 30-day rats and enhances phorbol ester-induced potentiation in 60-day rats. Protein kinase C (PKC) has been implicated in actions of lead but previous investigations have reported either a stimulation or a blockade of PKC by lead. Our results are consistent with the hypothesis that the effects of lead on LTP are mediated via an action on PKC, which varies with age.
Hussain
R J
RJ
Department of Environmental Health and Toxicology, School of Public Health, University at Albany, One University Place, B242, Rensselaer, NY 12144, USA.
Parsons
P J
PJ
Carpenter
D O
DO
D000367:Age Factors; D000818:Animals; D002273:Carcinogens / Q000494:pharmacology; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects; D005260:Female; D006624:Hippocampus / Q000166:cytology / Q000254:growth & development* / Q000502:physiology*; D007854:Lead / Q000633:toxicity*; D017774:Long-Term Potentiation / Q000187:drug effects*; D008297:Male; D019599:Mossy Fibers, Hippocampal / Q000187:drug effects / Q000201:enzymology; D009473:Neuronal Plasticity / Q000187:drug effects; D009924:Organ Culture Techniques; D010703:Phorbol Esters / Q000494:pharmacology; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011493:Protein Kinase C / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
D002273:Carcinogens; D010703:Phorbol Esters; D007854:Lead; D011493:Protein Kinase C