RT Journal Article
SR Electronic
T1 Eosine-Induced Blockade ofN-Methyl-d-aspartate Channels in Acutely Isolated Rat Hippocampal Neurons
JF Molecular Pharmacology
JO Mol Pharmacol
FD American Society for Pharmacology and Experimental Therapeutics
SP 334
OP 341
VO 57
IS 2
A1 Alexander I. Sobolevsky
A1 Maria V. Yelshansky
A1 Boris I. Khodorov
YR 2000
UL http://molpharm.aspetjournals.org/content/57/2/334.abstract
AB Acutely isolated rat hippocampal neurons were voltage-clamped in the whole-cell configuration. The currents throughN-methyl-d-aspartate (NMDA) channels were elicited by fast application of aspartate in a Mg2+-free 3 μM glycine-containing solution. Eosine, known as a potent reversible inhibitor of the plasma membrane Ca2+ pump, proved to be able to induce a blockade of NMDA channels. The eosine-induced inhibition of NMDA-mediated currents enhanced with eosine concentration (IC50 = 248 μM) but did not depend on the membrane potential, agonist (aspartate) or coagonist (glycine) concentrations, pH, or the presence of spermine, ethanol, and the disulfide-reducing agents dithiothreitol and glutathione. Zn2+ inhibited NMDA channels with equal efficiency both in the presence and absence of eosine. These results suggest that eosine interacts with a new, previously unknown NMDA receptor regulatory site. The American Society for Pharmacology and Experimental Therapeutics