Figure 4. In “older” neurons (13-16 DIV), the combination of ifenprodil and PEAQX but not individual inhibitors applied separately completely prevented glutamate-induced sustained elevation in [Ca²⁺]_c.

Neurons were loaded with 2.6μM Fura-2FF-AM. In A-D, neurons were exposed to 25μM glutamate (Glu, plus 10μM glycine). Where indicated, vehicle (0.2% DMSO), 50μM ifenprodil or 5μM PEAQX, or a combination of 1μM ifenprodil and 0.1μM PEAQX were applied. The time scale shown in panel D is applicable to traces in A-C. In E, statistical analysis of glutamate-induced [Ca²⁺]_c changes over time. Data are mean±SEM, *p<0.05, **p<0.01 compared to vehicle, n=3.