Opposite effects of lead exposure on taurine- and HFS-induced LTP in rat hippocampus.
The effect of lead exposure on taurine-induced long-term potentiation (LTP(TAU)) was examined and compared with high-frequency stimulation-induced one (LTP(HFS)). Field excitatory postsynaptic potentials (fEPSP) and fiber volley (FV) in area CA1 of hippocampal slice were recorded in control and lead-exposed rats. In contrast to the inhibitory effects of lead exposure on LTP(HFS), the amplitude of LTP(TAU) in the lead-exposed rats (199.3+/-13.7%, n=12) was significantly larger than that in controls (152.3+/-17.0%, n=12). It was also observed that taurine induced greater FV potentiation in lead-exposed rats (162.6+/-9.0%, n=10) than controls (132.1+/-6.9%, n=11). In addition, after a previous HFS, sequent perfusion of taurine could further increase the synaptic efficacy in lead-exposed rats. These results provide the first evidence that chronic lead exposure has opposite effects on the two types of LTP resulting from different lead toxicity sites.
Yu
Kuai
K
School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China.
Yu
Shan-Shan
SS
Ruan
Di-Yun
DY
D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn; D004347:Drug Interactions; D004558:Electric Stimulation / Q000379:methods*; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000528:radiation effects; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D066298:In Vitro Techniques; D007854:Lead / Q000097:blood / Q000633:toxicity*; D017774:Long-Term Potentiation / Q000187:drug effects* / Q000502:physiology / Q000528:radiation effects; D009433:Neural Inhibition / Q000187:drug effects / Q000528:radiation effects; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013654:Taurine / Q000494:pharmacology*; D013997:Time Factors
D013654:Taurine; D007854:Lead