Details

Autor(en) / Beteiligte

• Berretta, N.
• Berton, F.
• Bianchi, R.
• Brunelli, M.
• Capogna, M.
• Francesconi, W.

Titel

Long-term Potentiation of NMDA Receptor-mediated EPSP in Guinea-pig Hippocampal Slices

Ist Teil von

• The European journal of neuroscience, 1991-09, Vol.3 (9), p.850-854

Ort / Verlag

Oxford, UK: Blackwell Publishing Ltd

Erscheinungsjahr

1991

Quelle

Wiley Online Library

Beschreibungen/Notizen

• Hippocampal slices from guinea‐pigs were used to examine the long‐term potentiation (LTP) of the N‐methyl‐D‐aspartate (NMDA)‐mediated excitatory postsynaptic potential (EPSP). lntracellular recordings were performed from CA1 pyramidal neurons in the presence of 6‐cyano‐7‐nitroquinoxaline‐2,3‐dione (CNQX, 5–10 μM) and picrotoxin (50 μM). In these experimental conditions test stimuli applied at low frequency (0.1 Hz) to the Schaffer collateral ‐ commissural pathway evoked a prolonged EPSP (150–200 ms). To obtain this CNQX‐resistant EPSP, stimulus intensities had to be raised above the level required to evoke an EPSP of comparable amplitude in physiological solution. Tetanic stimulation (two trains of 100 Hz, 1 s every 20 s) led to a potentiation of the CNQX‐resistant EPSP, and this potentiated response was abolished with d‐(‐)‐2‐amino‐5‐phosphonovaleric acid (50μM). The potentiation of the NMDA receptor‐mediated EPSP was more pronounced for strong than for weak test stimuli, and was suppressed when test EPSPs were evoked during membrane hyperpolarization. These results suggest that NMDA receptor‐mediated responses can undergo LTP, and hence can contribute to the maintenance of LTP.