Table 2.

Mean (±SEM) head-down sniffing counts of DMSO- and EEDQ-treated preweanling rats (n = 8 per group) on time blocks 9–16 (Experiment 2)

DMSO Condition
Nonprotected		SCH/Sul Protection
0 μg NPA	0.39 (±0.20)	0 μg NPA	0.72 (±0.31)
10 μg NPA	9.17 (±0.55)*‡	10 μg NPA	11.03 (±0.64)*‡
20 μg NPA	11.76 (±0.66)*†‡	20 μg NPA	13.45 (±0.46)*†‡

EEDQ Condition
Nonprotected		SCH/Sul Protection
0 μg NPA	0.95 (±0.39)	0 μg NPA	1.03 (±0.46)
10 μg NPA	4.17 (±0.59)*	10 μg NPA	11.05 (±0.41)*‡
20 μg NPA	2.17 (±0.88)	20 μg NPA	13.33 (±0.28)*†‡

Head-down sniffing values represent mean scores per 5-min time block during the final 40-min testing phase.

^*Significantly different from the 0 μg NPA group in the same treatment condition;

^†Significantly different from the 10 μg NPA group in the same treatment condition;

^‡Significantly different from rats in the EEDQ-nonprotected condition receiving the identical dose of NPA.