Article

Repeated administration of imipramine attenuates glutamatergic transmission in rat frontal cortex.

Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland.
Neuroscience (impact factor: 3.38). 06/2008; 153(3):789-95. DOI:10.1016/j.neuroscience.2008.03.007
Source: PubMed

ABSTRACT The effects of repeated administration of a tricyclic antidepressant, imipramine, lasting 14 days (10 mg/kg p.o., twice daily), were studied ex vivo in rat frontal cortex slices prepared 48 h after last dose of the drug. In slices prepared from imipramine-treated animals the mean frequency, and to a lesser degree the mean amplitude, of spontaneous excitatory postsynaptic currents recorded from layer II/III pyramidal neurons, were decreased. These effects were accompanied by a reduction of the initial slope ratio of pharmacologically isolated N-methyl-D-aspartate to AMPA/kainate receptor-mediated stimulation-evoked excitatory postsynaptic currents. Imipramine treatment also resulted in a decrease of extracellular field potentials evoked in layer II/III by stimulation of underlying sites in layer V. These results indicate that chronic treatment with imipramine results in an attenuation of the release of glutamate and an alteration in the postsynaptic reactivity of ionotropic glutamate receptors in rat cerebral cortex.

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Keywords

AMPA/kainate receptor-mediated stimulation-evoked excitatory postsynaptic currents
 
attenuation
 
ex vivo
 
extracellular field potentials evoked
 
imipramine
 
imipramine results
 
Imipramine treatment
 
imipramine-treated animals
 
initial slope ratio
 
last dose
 
lasting 14 days
 
layer II/III
 
layer II/III pyramidal neurons
 
lesser degree
 
mean amplitude
 
postsynaptic reactivity
 
spontaneous excitatory postsynaptic currents
 
tricyclic antidepressant