PT - JOURNAL ARTICLE AU - Alexander I. Sobolevsky AU - Maria V. Yelshansky AU - Boris I. Khodorov TI - Eosine-Induced Blockade of<em>N</em>-Methyl-<span class="sc">d</span>-aspartate Channels in Acutely Isolated Rat Hippocampal Neurons DP - 2000 Feb 01 TA - Molecular Pharmacology PG - 334--341 VI - 57 IP - 2 4099 - http://molpharm.aspetjournals.org/content/57/2/334.short 4100 - http://molpharm.aspetjournals.org/content/57/2/334.full SO - Mol Pharmacol2000 Feb 01; 57 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