A chemical LTP induced by co-activation of metabotropic and N-methyl-D-aspartate glutamate receptors in hippocampal CA1 neurons.
In CA1 neurons of guinea pig hippocampal slices, long-term depression (LTD) was induced in the field EPSP response in the absence of test synaptic inputs (one stimulus every 20 s) by application of the metabotropic glutamate receptor (mGluR) agonist, aminocyclopentane-1S, 3R-dicarboxylic acid (ACPD). This effect was blocked and long-term potentiation (LTP) was induced by co-application of N-methyl-D-aspartate (NMDA) during ACPD perfusion (ACPD/NMDA-induced LTD). These results indicate that the state of NMDA receptor activation during ACPD perfusion determines whether LTP or LTD is induced in hippocampal CA1 neurons. Co-application of an inositol 1, 4, 5-trisphosphate (IP3) receptor inhibitor, 2-aminotheoxydiphenyl borate, during ACPD application had no effect on the ACPD/NMDA-induced LTP, but increased the magnitude of the ACPD-induced LTD, suggesting that the ACPD/NMDA-induced LTP involves NMDA receptors, but not IP3 receptors, whereas the converse applies to the ACPD-induced LTD.
Fujii
Satoshi
S
Department of Physiology, Yamagata University School of Medicine, Yamagata 990-9585, Japan. sfujii@med.id.yamagata-u.ac.jp
Sasaki
Hiroshi
H
Mikoshiba
Katsuhiko
K
Kuroda
Yoichiro
Y
Yamazaki
Yoshihiko
Y
Mostafa Taufiq
Ahmed
A
Kato
Hiroshi
H
D000818:Animals; D015220:Calcium Channels / Q000378:metabolism; D004148:Dioxolanes / Q000494:pharmacology; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology; D006168:Guinea Pigs; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D066298:In Vitro Techniques; D015544:Inositol 1,4,5-Trisphosphate / Q000494:pharmacology; D053496:Inositol 1,4,5-Trisphosphate Receptors; D017774:Long-Term Potentiation / Q000187:drug effects / Q000502:physiology*; D008297:Male; D016202:N-Methylaspartate / Q000494:pharmacology; D009434:Neural Pathways / Q000187:drug effects / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D011687:Purines / Q000494:pharmacology; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D018160:Receptors, Cytoplasmic and Nuclear / Q000037:antagonists & inhibitors / Q000378:metabolism; D018094:Receptors, Metabotropic Glutamate / Q000187:drug effects / Q000378:metabolism*; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects / Q000378:metabolism*; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology*
D015220:Calcium Channels; D004148:Dioxolanes; D018690:Excitatory Amino Acid Agonists; D053496:Inositol 1,4,5-Trisphosphate Receptors; D011687:Purines; D018160:Receptors, Cytoplasmic and Nuclear; D018094:Receptors, Metabotropic Glutamate; D016194:Receptors, N-Methyl-D-Aspartate; C104068:4-(2-amino-6-chloro-9H-purin-9-yl)-1,3-dioxolane-2-methanol; D016202:N-Methylaspartate; D015544:Inositol 1,4,5-Trisphosphate