title: Effects of lead exposure on long-term potentiation induced by 2-deoxy-D-glucose in area CA1 of rat hippocampus in vitro.
abstract: Chronic developmental lead exposure is known to be associated with cognitive dysfunction in children. Previous studies have demonstrated that chronic lead exposure could impair the induction and maintenance of long-term potentiation induced by high-frequency stimulation (HFS-LTP). In area CA1 of rat hippocampus, long-term potentiation could also be induced following temporary replacement of 10 mM 2-deoxy-D-glucose (2-DG) for 10 mM glucose in the normal perfusate (artificial cerebrospinal fluid). The present study was carried out to investigate whether chronic lead exposure affected long-term potentiation induced by 2-DG (2-DG-LTP). Neonatal Wistar rats were exposed to lead from parturition to weaning via milk of dams whose drinking water contained 0.2% lead acetate. Field excitatory postsynaptic potentials (EPSPs) in area CA1 of hippocampus were recorded on postnatal days 25-30. 2-DG application was followed by an increase in EPSP slopes in a time-course-dependent manner in both control and lead-exposed rats, while the amplitude of 2-DG-LTP in the lead-exposed rats (225.9+/-19.0%, n=12) was significantly greater than that in controls (155.2+/-9.8%, n=12). In contrast to the effects of lead exposure on 2-DG-LTP, the amplitude of HFS-LTP in the lead-exposed rats (121.5+/-13.7%, n=12) was significantly less than that in controls (183.9+/-18.6%, n=12). These results indicate that chronic lead exposure had opposite effects on the two types of LTP induced by HFS and 2-DG. This would suggest that the effects of lead on HFS-LTP and 2-DG-LTP are the result of different sites of lead toxicity.
authors.affiliation: School of Life Science, University of Science and Technology of China, Anhui, 230027, Hefei, China.
authors.forename: L
authors.initials: L
authors.lastname: Cai
authors.forename: D Y
authors.initials: DY
authors.lastname: Ruan
authors.forename: Y Z
authors.initials: YZ
authors.lastname: Xu
authors.forename: Z
authors.initials: Z
authors.lastname: Liu
authors.forename: X M
authors.initials: XM
authors.lastname: Meng
authors.forename: X Q
authors.initials: XQ
authors.lastname: Dai
mesh_terms: D000818:Animals; D003847:Deoxyglucose / Q000494:pharmacology*; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects; D006624:Hippocampus / Q000187:drug effects* / Q000502:physiology; D066298:In Vitro Techniques; D007854:Lead / Q000493:pharmacokinetics / Q000633:toxicity*; D017774:Long-Term Potentiation / Q000187:drug effects*; D051381:Rats; D013997:Time Factors
chemical_list: D007854:Lead; D003847:Deoxyglucose