Long-term potentiation in the optic tectum of rainbow trout.
We examined synaptic plasticity in the optic tectum of rainbow trout by extracellular recordings. We found that the field-excitatory postsynaptic potential in the retinotectal synapses was potentiated by repetitive stimuli of 1.0 Hz for 20 s to the retinotectal afferents. The long-term potentiation (LTP) developed slowly, and was maintained for at least 2 h. Applications of an antagonist for N-methyl-D-aspartic acid (NMDA) receptors or Mg2+ -free saline showed that activation of NMDA receptors was required to form the LTP beyond the induction period. The present findings indicate that presynaptic stimulation in the retinotectal synapses causes LTP mediated by NMDA receptors in the optic tectum of rainbow trout.
Division of Biological Sciences, Graduate School of Science, Hokkaido University, North 10, West 8, Kita-ku, Sapporo 060-0810, Japan.
Masae
M
Kinoshita
Toshiyuki
T
Hosokawa
Akihisa
A
Urano
Etsuro
E
Ito
D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000779:Anesthetics, Local / Q000494:pharmacology; D000818:Animals; D019256:Cadmium Chloride / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D004558:Electric Stimulation; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000528:radiation effects; D017774:Long-Term Potentiation / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D017686:Oncorhynchus mykiss; D013477:Superior Colliculi / Q000502:physiology*; D013779:Tetrodotoxin / Q000494:pharmacology; D013997:Time Factors; D014633:Valine / Q000031:analogs & derivatives* / Q000494:pharmacology
D000779:Anesthetics, Local; D018690:Excitatory Amino Acid Agonists; D018691:Excitatory Amino Acid Antagonists; D013779:Tetrodotoxin; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; C056639:2-amino-5-phosphopentanoic acid; D014633:Valine; D019256:Cadmium Chloride; D002118:Calcium