title: Effects of dimethylarsinic and dimethylarsinous acid on evoked synaptic potentials in hippocampal slices of young and adult rats.
abstract: In this study, the effects of pentavalent dimethylarsinic acid ((CH(3))(2)AsO(OH); DMA(V)) and trivalent dimethylarsinous acid ((CH(3))(2)As(OH); DMA(III)) on synaptic transmission generated by the excitatory Schaffer collateral-CA1 synapse were tested in hippocampal slices of young (14-21 day-old) and adult (2-4 month-old) rats. Both compounds were applied in concentrations of 1 to 100 micromol/l. DMA(V) had no effect on the amplitudes of evoked fEPSPs or the induction of LTP recorded from the CA1 dendritic region either in adult or in young rats. However, application of DMA(III) significantly reduced the amplitudes of evoked fEPSPs in a concentration-dependent manner with a total depression following application of 100 micromol/l DMA(III) in adult and 10 micromol/l DMA(III) in young rats. Moreover, DMA(III) significantly affected the LTP-induction. Application of 10 micromol/l DMA(III) resulted in a complete failure of the postsynaptic potentiation of the fEPSP amplitudes in slices taken both from adult and young rats. The depressant effect was not reversible after a 30-min washout of the DMA(III). In slices of young rats, the depressant effects of DMA(III) were more pronounced than in those taken from adult ones. Compared to the (absent) effect of DMA(V) on synaptic transmission, the trivalent compound possesses a considerably higher neurotoxic potential.
authors.affiliation: Institut für Physiologie I, Universitätsklinikum Münster, Robert-Koch-Strasse 27a, D-48149 Münster, Germany. katharina.krueger@uni-muenster.de
authors.forename: Katharina
authors.initials: K
authors.lastname: Krüger
authors.forename: Hendrik
authors.initials: H
authors.lastname: Repges
authors.forename: Jörg
authors.initials: J
authors.lastname: Hippler
authors.forename: Louise M
authors.initials: LM
authors.lastname: Hartmann
authors.forename: Alfred V
authors.initials: AV
authors.lastname: Hirner
authors.forename: Heidrun
authors.initials: H
authors.lastname: Straub
authors.forename: Norbert
authors.initials: N
authors.lastname: Binding
authors.forename: Ulrich
authors.initials: U
authors.lastname: Musshoff
mesh_terms: D000367:Age Factors; D000818:Animals; D020261:Arsenic Poisoning / Q000503:physiopathology; D002101:Cacodylic Acid / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004785:Environmental Pollutants / Q000008:administration & dosage / Q000633:toxicity*; D005071:Evoked Potentials / Q000187:drug effects; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects*; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D017774:Long-Term Potentiation / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar
chemical_list: D004785:Environmental Pollutants; C472511:dimethylarsinous acid; D002101:Cacodylic Acid