((2S, 3R)‐3‐hydroxy‐2‐((R)‐5‐isobutyryl‐1‐oxo‐2,5‐diazaspiro[3,4]octan‐2‐yl) butanamide (NYX‐2925) pre‐treatment facilitates chemical long‐term potentiation (chemLTP)‐mediated synaptic amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid receptor subunit 1 (GluA1) recruitment. (a) As before, neurons (14 days in vitro) were changed to artificial cerebrospinal fluid (aCSF) and allowed to recover for 30 min at 37°C. Next, cells were co‐treated with 1 picomolar NYX‐2925 and 50 μM glutamate and colocalization of GluA1‐containing α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid receptor with post‐synaptic density protein 95 (PSD‐95) quantified. Cells from the same cultures underwent chemLTP stimulation following NYX‐2925/glutamate pre‐treatment. (b–d) Representative cellular immunolabeling of GluA1 and PSD‐95. (b′–d′) Representative dendrites immunolabeled for GluA1 and PSD‐95. (e) Co‐incubation with 1 pM NYX‐2925 and glutamate in the absence of chemLTP did not affect colocalization of GluA1 with PSD‐95. (f) chemLTP stimulation increased colocalization, and this effect was facilitated by 1 pM NYX‐2925/glutamate pre‐treatment. Veh: vehicle. Scale bar = 10 μm. Data represent mean ± SEM ± data spread; the line within each box represents the average, the box itself represents the SEM, and the whiskers indicate the spread of the data. ***p < 0.001, **p < 0.01, *p < 0.05 Tukey post hoc analysis, n = 14 cells per treatment from two independent cell culture preparations (eight coverslips). MAP2, Microtubule associated protein 2.