Potentiation of prelimbic field potentials during and seconds after trains of excitations in the rat hippocampo-prefrontal pathway.
Field potentials were recorded in the prelimbic cortex of anaesthetized rats after excitations of the hippocampo-prefrontal pathway. Stimuli were delivered to the hippocampal CA1 region and short-term changes of field potential amplitudes were observed in two situations. (1) Amplitudes were monitored during trains of stimulations given at frequencies between 1 and 20 Hz. Within trains, potentiation was followed by depression. Both types of changes were frequency dependent. (2) The time course of recovery from within-train plasticity was obtained from field potentials evoked at varying intervals after trains. This revealed a post-train potentiation having a maximum after 2-4 s and lasting for approximately 10 s. The maximal post-train potentiation was nearly independent of the frequency of the preceding train.
Christoffersen
G R J
GR
August Krogh Institute, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen, Denmark. grj@christoffersen.mail.dk
Petersen
S
S
daCosta
N M
NM
D000818:Animals; D004558:Electric Stimulation; D005071:Evoked Potentials / Q000502:physiology*; D006624:Hippocampus / Q000502:physiology*; D008032:Limbic System / Q000502:physiology*; D009433:Neural Inhibition; D009434:Neural Pathways / Q000502:physiology*; D009473:Neuronal Plasticity / Q000502:physiology; D017397:Prefrontal Cortex / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D013997:Time Factors