Mean distance traveled (±SEM) during the 80-min behavioral testing session on PD 18 (n = 8 per group). Rats were given IP injections of SCH23390/sulpiride (D1/D2 protected) or saline/saline (nonprotected) prior to EEDQ or DMSO infusions. At the conclusion of time block 8 (indicated by the second dashed line), EEDQ- and DMSO-treated preweanling rats received bilateral infusions of NPA (0, 10, or 20 μg).
† Significantly different from rats in the DMSO-nonprotected group (collapsed across time blocks).
‡ Significantly different from DMSO-treated rats.
* Significantly different from rats in the same treatment conditions infused with 0 μg NPA (collapsed across time blocks 9–16).
^ Significantly different from rats in the other treatment conditions infused with 10 or 20 μg NPA (collapsed across time blocks 9–16).