Ferrous iron modulates quinolinate-mediated [3H]MK-801 binding to rat brain synaptic membranes in the presence of glycine and spermidine.
Quinolinic acid (QUIN) displaced binding of agonist and antagonist ligands for the N-methyl-D-aspartate (NMDA) receptor in rat brain synaptic membranes. Both QUIN and glutamic acid (GLU) potentiated binding of [3H]dizocilpine (MK-801) in the presence of glycine (GLY) alone, whereas the potentiation by QUIN was in a bell-shaped fashion in contrast to that by GLU. However, further addition of spermidine (SPD) induced bell-shaped potentiation by GLU as well as QUIN. The potentiation by QUIN was markedly deteriorated by the further addition of FeCl2 irrespective of the presence of GLY and SPD added. These results suggest that QUIN may potentiate [3H]MK-801 binding to the open NMDA channel in rat brain synaptic membranes through a mechanism different from that underlying the potentiation by GLU.
St'astny
F
F
Department of Molecular Neurobiology, Institute of Physiology, Academy of Sciences, Prague, Czech Republic.
Hinoi
E
E
Ogita
K
K
Yoneda
Y
Y
D015763:2-Amino-5-phosphonovalerate / Q000031:analogs & derivatives / Q000494:pharmacology; D000494:Allosteric Regulation; D000818:Animals; D001665:Binding Sites; D001921:Brain / Q000166:cytology / Q000378:metabolism; D016291:Dizocilpine Maleate / Q000378:metabolism*; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005296:Ferrous Compounds / Q000494:pharmacology*; D018698:Glutamic Acid / Q000378:metabolism / Q000494:pharmacology; D005998:Glycine / Q000494:pharmacology*; D020128:Inhibitory Concentration 50; D007736:Kynurenic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D008297:Male; D017378:Quinolinic Acid / Q000037:antagonists & inhibitors / Q000378:metabolism / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism; D013095:Spermidine / Q000494:pharmacology*; D013570:Synaptic Membranes / Q000378:metabolism*
D018691:Excitatory Amino Acid Antagonists; D005296:Ferrous Compounds; D016194:Receptors, N-Methyl-D-Aspartate; C069052:CGP 39653; D018698:Glutamic Acid; D016291:Dizocilpine Maleate; D015763:2-Amino-5-phosphonovalerate; D017378:Quinolinic Acid; D007736:Kynurenic Acid; C029451:ferrous chloride; C066192:5,7-dichlorokynurenic acid; D005998:Glycine; D013095:Spermidine