Fig. 9.

Low-dose NMDA application does not recapitulate HCY-induced reduction of desensitization. Because HCY was capable of inducing small AP5-blockable currents, we tested the hypothesis that doses of NMDA that induce current amplitudes similar to those produced by HCY could recapitulate HCY's effects on desensitization. Initial application of 2 μM NMDA to neurons (blue trace, 200 nM GLY) induced an NMDAR current similar in amplitude to HCY application (compare with Fig. 1). However, when 100 μM NMDA were then applied, desensitization was not reduced (N = 4), and charge transfer was never enhanced.