ABSTRACT The aim of this study was to determine the capacity of copper to modify synaptic hyperexcitability generated by penicillin G. This epileptogenic drug was studied with CA1 neurons of the rat hippocampus. Hippocampal slices were extracted from adult male Wistar rats (n = 16). The field potentials (FP) were registered in CA1 neurons after electrical stimulation from the stratum radiatum. The mean voltage and duration of FP were measured during control, penicillin G, copper and washout stages. Copper (100 μM) significantly decreased mean FP voltage compared to the control and penicillin stages. However, during the washout stage, the mean FP voltage was significantly higher than in the penicillin stage. Regarding the FP duration, 100 μM of copper significantly decreased the mean FP during the penicillin stage. After the washing stage, the mean FP lasted significantly longer. Thus, administering copper modified CA1 synapses by blocking hippocampal neuronal excitability was generated by the epileptic agent.
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