title: Tetrodotoxin reveals action of spermine at presynaptic N-methyl-D-aspartate receptors.
abstract: By testing the effect of spermine on N-methyl-D-aspartate (NMDA)-evoked [3H]noradrenaline release in rat hippocampal slices, we revealed a presynaptic spermine-sensitive NMDA receptor most probably localized on noradrenergic terminals. Spermine (1 mM), per se totally inactive, was able to reverse the tetrodotoxin-induced blockade of the NMDA effect, restoring tritium efflux to approximately 50% of the NMDA-evoked release measured in the absence of tetrodotoxin. This effect was partially antagonized by D(-)-2-amino-7-phosphonoheptanoic acid. Our results may help to elucidate the role that spermine exerts on excitatory amino acids receptors.
authors.affiliation: CNS&CV Research Group, Farmitalia Carlo Erba-Erbamont Group, Milano, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Speciale
authors.forename: L
authors.initials: L
authors.lastname: Facheris
authors.forename: R G
authors.initials: RG
authors.lastname: Fariello
mesh_terms: D000818:Animals; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D066298:In Vitro Techniques; D008297:Male; D009638:Norepinephrine / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects*; D013096:Spermine / Q000494:pharmacology*; D013779:Tetrodotoxin / Q000494:pharmacology*
chemical_list: D016194:Receptors, N-Methyl-D-Aspartate; D013096:Spermine; D013779:Tetrodotoxin; D009638:Norepinephrine