Figure 1

Time to mount a hidden platform during the first (juvenile; panel A) and second (young-adult; panel B) water maze test. Rats were treated (through the maternal circulation) with either 100 mg/kg ketamine HCl (i.p.) or saline on either E18 or E19 and then tested later on P18 and P81. The data presented here illustrate raw latencies without taking into account the time the animals spent treading water (i.e., not making forward progress). Panel A: P18 rats generally decreased their latencies to mount the hidden platform over the 10 trials. This effect was most prominent over the first 3 trials. The behavioral changes induced by drug or age manipulations were not statistically significant. Panel B: P81 rats all readily re-learned the location of the hidden platform as there was a significant reduction in time to mount the platform over the 10 trials. The analysis (see text) also revealed a significant Age X Drug interaction which was most prominent on trial 1 (see also Figure 3). Data were analyzed using a three-way ANOVA [Drug (100 mg/kg ketamine HCl, saline control) X Treatment age (E18, E19) X Time] with time blocks as the repeated time factor and compensation for unequal Ns. Variance indicators are the Standard Error of the Mean (SEM).