Direct evidence for increase in excitatory amino acids release during mossy fiber LTP in rat hippocampal slices as revealed by the patch sensor methods.
We had previously established a patch sensor system for detecting overflow of excitatory amino acids (EAA) from hippocampal slices induced by a single electric stimulus. We performed simultaneous recordings of patch sensor current and whole-cell current in rat hippocampal slices. Tetanus of mossy fibers produced long-term potentiation (LTP) of excitatory postsynaptic current (EPSC) recorded from a CA3 pyramidal cell with an increase in single electric stimulus-evoked patch current amplitude recorded with a patch sensor positioned in the stratum lucidum. In Schaffer collateral-CA1 synapses, however, LTP of EPSC was accompanied by an increase in AMPA-evoked whole-cell current, but not with change in patch current in the stratum radiatum. These results indicate that EAA release is increased during mossy fiber LTP but not CA1 LTP.
Maeda
T
T
Department of Pharmacology, Faculty of Pharmaceutical Science, Kyoto university, Japan.
Kaneko
S
S
Akaike
A
A
Satoh
M
M
D000818:Animals; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D018698:Glutamic Acid / Q000378:metabolism*; D006624:Hippocampus / Q000502:physiology*; D017774:Long-Term Potentiation / Q000502:physiology*; D009924:Organ Culture Techniques; D018408:Patch-Clamp Techniques; D051381:Rats; D013744:Tetanus Toxin / Q000494:pharmacology; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000494:pharmacology
D018690:Excitatory Amino Acid Agonists; D013744:Tetanus Toxin; D018698:Glutamic Acid; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid