NMDA receptors ethanol affecting

In order to confirm the possible interaction of ethanol and crocin on NMDA receptors, we also performed whole-cell patch recording with primary cultured hippocampal neurons and measured membrane currents induced by the application of NMDA in a voltage-clamped condition. Application of 100 pM NMDA induced an inward current of 100.2 9.8 pA (n=10) at a holding potential of -60 mV. The NMDA-induced inward current was not affected by 10 pM CNQX (data not shown), but was completely abolished by 30 pM APV, supporting the fact that the response was mediated by NMDA receptors. Ethanol inhibited NMDA-induced currents in a concentration-dependent manner. Crocin (10 pM) had no effect on NMDA-induced currents by itself (data not shown), but attenuated the inhibitory effect of ethanol on NMDA-induced currents. The concentration-effect curve for ethanol was shifted to the right by the presence of crocin [22]. 

The synapic potential mediated by non-NMDA receptors was recorded in normal ACSF. When ethanol (10-50 mM) was added to the perfusing medium, no significant change in non-NMDA receptor-mediated synaptic potential was observed. However, the addition of ethanol at a higher concentration (100 mM) induced a small reduction in non-NMDA receptor-mediated synaptic potential (Fig.(5)A). The reduction in non-NMDA response rapidly occurred after the addition of 100 mM ethanol and reached a steady state within 10 min. After washing out the ethanol, the response gradually returned to the normal level. When 10 pM crocin was added 10 min prior to the ethanol, the non-NMDA response was similarly reduced in the presence of 100 mM ethanol (Fig.(5)B). Crocin (10 pM) did not significantly affect the inhibitory effect of 100 mM ethanol on non-NMDA response (Fig.(5)C) [22],... 

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