Expression of early hippocampal CA1 LTP does not lead to changes in AMPA-EPSC kinetics or sensitivity to cyclothiazide

Gerhard Rammes, Hanns Ulrich Zeilhofer, Graham L. Collingridge, Chris G. Parsons, Dieter Swandulla

Research output: Contribution to journalArticlepeer-review

15 Scopus citations

Abstract

We have analysed whether the expression of long-term potentiation (LTP) in rat hippocampal CA1 neurons involves a change in the kinetics of (s)-α- amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor-mediated excitatory postsynaptic currents (EP-SCs) (AMPA-EPSCs) or their susceptibility to the AMPA receptor modulator cyclothiazide. AMPA-EPSCs in the CA1 region were evoked by alternate stimulation of two independent Schaffer collateral-commissural inputs of slices of adult rat hippocampus. In the current-clamp mode a strong tetanus (100 Hz, 1 s) applied to one input (input I) induced stable LTP of AMPA-EPSCs in this input, while the control input (input II) remained unaffected. For neither input were EPSC rise time and decay kinetics significantly changed. The application of cyclothiazide prolonged the rise time and the decay time constants of the AMPA-EPSCs in both control and potentiated inputs to the same extent (Input I-rise time: 198±8%, decay: 148±12%; input II-rise time: 212±14%, decay: 144±19%; n=8). Furthermore, when present during tetanization cyclothiazide did not occlude LTP, suggesting that cyclothiazide and tetanic stimulation enhance AMPA-EPSCs via independent mechanisms. Our findings argue against changes in (de-)activation or desensitization of AMPA receptors as the molecular basis for the expression of LTP.

Original languageEnglish
Pages (from-to)191-196
Number of pages6
JournalPflugers Archiv European Journal of Physiology
Volume437
Issue number2
DOIs
StatePublished - 1999
Externally publishedYes

Keywords

  • AMPA receptor-mediated EPSCs
  • Cyclothiazide
  • Hippocampus
  • Kinetics
  • Long- term potentiation (LTP)
  • Rat

Fingerprint

Dive into the research topics of 'Expression of early hippocampal CA1 LTP does not lead to changes in AMPA-EPSC kinetics or sensitivity to cyclothiazide'. Together they form a unique fingerprint.

Cite this