NMDAR antagonism has no differential effect on bAP-evoked Ca²⁺ signals in dendrites or spines.

<p>A. Top left: 2PLSM image of a spine and dendrite with dashed line indicating line scan position. Bottom left: During a 500 Hz line scan through spine and dendrite, a bAP (arrow) evokes a Ca²⁺ transient in both compartments. Right: Somatic AP evoked by current injection. B, C. Average Ca²⁺ transients evoked by a bAP measured in the dendrite (left) and spine (right) from a P14 animal (B; n = 11 for both structures) and a P34 animal (C; spine, n = 17; dendrite, n = 13) in the presence and absence of D-AP5 (10–50 µM).</p