L-AP3 blocks rises in intracellular calcium associated with hippocampal CA1 LTP.
The involvement of type I metabotropic glutamate receptors in hippocampal CA1 long-term potentiation (LTP) depends on the applied tetanic stimulation protocol. Activation of these receptors may cause an elevation of intracellular calcium via the formation of the second messenger inositol triphosphate (IP3) and subsequent intracellular calcium release. It has been shown that the type I metabotropic receptors antagonist L-2-amino-3-phosphonopropionate (L-AP3) blocks CA1 LTP. Combining dendritic calcium and field potential measurements in CA1 hippocampal area, we found that L-AP3 did not affect single calcium transients but reduced the calcium changes evoked by a single tetanus, preventing the long-lasting calcium enhancements associated with CA1 LTP. These findings suggest that the formation of this type of LTP requires calcium release from IP3-sensitive stores.
Matias
Carlos
C
Physics Department, University of Trás-os-montes e Alto Douro, 5001-911 Vila Real, Portugal.
Foley
Paul
P
Quinta-Ferreira
M Emilia
ME
D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000409:Alanine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D000818:Animals; D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling / Q000187:drug effects / Q000502:physiology*; D004558:Electric Stimulation; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology*; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology; D005456:Fluorescent Dyes; D016257:Fura-2; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D007424:Intracellular Fluid / Q000187:drug effects / Q000378:metabolism*; D017774:Long-Term Potentiation / Q000187:drug effects / Q000502:physiology*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D018094:Receptors, Metabotropic Glutamate / Q000037:antagonists & inhibitors / Q000378:metabolism*; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors / Q000378:metabolism; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D015854:Up-Regulation / Q000187:drug effects / Q000502:physiology
D018691:Excitatory Amino Acid Antagonists; D005456:Fluorescent Dyes; D018094:Receptors, Metabotropic Glutamate; D016194:Receptors, N-Methyl-D-Aspartate; C000211:2-amino-3-phosphonopropionic acid; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D015763:2-Amino-5-phosphonovalerate; D015544:Inositol 1,4,5-Trisphosphate; D000409:Alanine; D002118:Calcium; D016257:Fura-2