Table 1.
Group sizes and sequence of testing
| Experiment | wt, SAL | wt, POL | Nurr1+/−, SAL | Nurr1+/−, POL | Age | |
|---|---|---|---|---|---|---|
| Cohort I | 1. Cytokine assay | 4 f | 4 f | 5 f | 5 f | P70 |
| Cohort II | 2. Open field exploration | 14 m | 14 m | 14 m | 14 m | P70 |
| 3. Prepulse inhibition | 14 m | 14 m | 14 m | 14 m | P75 | |
| 4. Latent inhibition | ||||||
| Non-preexposed | 7 m | 7 m | 7 m | 7 m | P85 | |
| Preexposed | 7 m | 7 m | 7 m | 7 m | P85 | |
| Cohort III | 5. Visual discriminationa | 7 m | 7 m | 7 m | 7 m | P70 |
| 6. Working memory | 7 m | 7 m | 7 m | 7 m | P100 | |
| 7. Immunohistochemistry | 7 m | 7 m | 7 m | 7 m | P130 |
Animals from cohort I were used to ascertain the effects of poly(I:C) (POL) (2 mg/kg, i.v.) treatment, relative to saline (SAL) treatment, on serum proinflammatory and antiinflammatory cytokine elevations in pregnant adult (P70) wild-type (wt) and Nurr1-deficient (Nurr1+/−) female (f) mice on gestation day 17 (Experiment 1). Experimental subjects in cohorts II and III included adult offspring from SAL- or POL-exposed wt and Nurr1+/− mothers. Offspring from cohort II were tested sequentially in Experiments 2–4 assessing open-field exploration, prepulse inhibition, and latent inhibition in adulthood (P70–P85). Experiments 2–4 were separated by a intertest resting period of 3–5 d. Offspring from cohort III were first subjected to a two-choice visual discrimination test (Experiment 5) and spatial working memory test (Experiment 6). These offspring were then given a resting period of 2 weeks before being assigned to immunohistochemical analyses (Experiment 7). Only male (m) subjects were included in all behavioral, cognitive, and immunohistochemical tests performed in animals from cohorts II and III; offspring in each group derived from multiple independent litters (7–10) in each of the four experimental conditions to avoid confounds from litter effects.
aTwo animals (1 Nurr1+/−, SAL, and 1 Nurr1+/−, POL) did not reach criterion during the acquisition phase of the two-choice visual discrimination task. The final number of animals included in the statistical analyses of the two-choice visual discrimination task was therefore N(wt, SAL) = 7, N(wt, POL) = 7, N(Nurr1+/−, SAL) = 6, N(Nurr1+/−, POL) = 6.