Gating effects of the lurcher mutation A8T on NMDA receptors. (A) Continuous 30-s segments were selected from minutes-long recordings obtained from one WT or one lurcher (N1^8T/N2 or N1/N2^8T) receptor (on-cell; open is down). (B) Dwell-time distributions calculated from the records illustrated in A are overlaid with probability distribution functions calculated from 5C4O models (thick) and individual closed or open kinetic components (thin). (C) Kinetic models optimized by fits to the entire sequence of closed and open intervals in each record; for each postulated transition, rate constants are given as rounded means for each dataset (in s⁻¹). *, significant difference relative to WT (P < 0.05; Student’s t test). All states (C, O) represent fully liganded (2 Glu, 2 Gly) receptors. (D) Whole-cell currents recorded during 5-s application of 1 mM Glu (gray) are overlaid with the trace simulated with the corresponding kinetic model in C (black, purple, or green). Traces were normalized to peak.