The antidepressant tianeptine persistently modulates glutamate receptor currents of the hippocampal CA3 commissural associational synapse in chronically stressed rats
by
Kole MH, Swan L, Fuchs E.
Division of Neurobiology,
German Primate Center,
Gottingen, Germany.
mhpkoledpz.gwdg.de
Eur J Neurosci. 2002 Sep;16(5):807-16.
ABSTRACTRecent hypotheses on the action of antidepressants imply a modulation of excitatory amino acid transmission. Here, the effects of long-term antidepressant application in rats with the drug tianeptine were examined at hippocampal CA3 commissural associational (c/a) glutamate receptor ion channels, employing the whole-cell patch-clamp technique. The drug's impact was tested by subjecting rats to daily restraint stress for three weeks in combination with tianeptine treatment (10 mg/kg/day). Whereas stress increased the deactivation time-constant and amplitude of the N-methyl-d-aspartate (NMDA) receptor-mediated excitatory postsynaptic currents (EPSCs), it did not affect the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA)/kainate receptor-mediated EPSCs. Concomitant pharmacological treatment of stressed animals with tianeptine resulted in a normalized scaling of the amplitude ratio of NMDA receptor to AMPA/kainate receptor-mediated currents and prevented the stress-induced attenuation of NMDA-EPSCs deactivation. Both paired-pulse-facilitation and frequency-dependent plasticity remained unchanged. Both in control and stressed animals, however, tianeptine treatment strengthened the slope of the input-output relation of EPSCs. The latter was mimicked by exposing hippocampal slices in vitro with 10 micro m tianeptine, which rapidly increased the amplitudes of NMDA- and AMPA/kainate EPSCs. The enhancement of EPSCs could be blocked by the intracellular presence of the kinase inhibitor staurosporine (1 micro m), suggesting the involvement of a postsynaptic phosphorylation cascade rather then presynaptic release mechanisms at CA3 c/a synapses. These results indicate that tianeptine targets the phosphorylation-state of glutamate receptors at the CA3 c/a synapse. This novel signal transduction mechanism for tianeptine may provide a mechanistic resolution for its neuroprotective properties and, moreover, a pharmacological trajectory for its memory enhancing and/or antidepressant activity.Neuroplasticity
Asthma prevention
Anxious depression
Tianeptine (Stablon)
Tianeptine: structure
Tianeptine and Panic Disorder
The glia glutamate transporter
Ethanol withdrawal and tianeptine
Discriminative stimulus properties
Neurobiology of mood, anxiety and emotion
Major depression and impaired structural plasticity
Synaptic plasticity in tianeptine-treated tree-shrews
Stress-induced hippocampal atrophy and dysfunction
Refs
and further readingHOME
HedWeb
Nootropics
cocaine.wiki
Future Opioids
BLTC Research
MDMA/Ecstasy
Superhapiness?
Utopian Surgery?
The Abolitionist Project
The Hedonistic Imperative
The Reproductive Revolution
Critique of Huxley's Brave New World
The Good Drug Guide
The Responsible Parent's Guide
To Healthy Mood Boosters For All The Family