Table 1.
Data (expressed as mean ± SEM) gathered in the light-dark box (LDB, Experiment 1) and elevated plus maze (EPM, Experiment 2) tests, and in the test for sensibility to the sedative and hypnotic effects of ethanol (Experiment 2).
| Males | Females | |||||||
|---|---|---|---|---|---|---|---|---|
| Environmental enrichment (EE) groups | Standard (Control, CTRL) housing groups | Environmental enrichment (EE) groups | Standard (Control, CTRL) housing groups | |||||
| LDB | Maternal separation (MS) | AFR | Maternal separation (MS) | AFR | Maternal separation (MS) | AFR | Maternal separation (MS) | AFR |
| Latency to exit the bright sector (s) | 28.10 ± 7.42 | 28.10 ± 7.42 | 29.76 ± 18.90 | 10.41 ± 3.64 | 17.73 ± 5.88 | 37.29 ± 16.16 | 28.99 ± 12.38 | 28.00 ± 6.2 |
| Transfers between sectors | 2.43 ± 0.36 | 2.43 ± 0.36 | 1.25 ± 0.62 | 2.12 ± 0.51 | 4.75 ± 0.82 (#) | 2.28 ± 0.75 (#) | 2.62 ± 0.59 (#) | 2.5 ± 0.57 (#) |
| Time in bright sector (s) | 2.42 ± 0.37 (&) | 2.42 ± 0.37 | 1.25 ± 0.62 | 2.62 ± 0.59 | 4.75 ± 0.82 (&) (#) | 2.28 ± 0.74 (#) | 1.25 ± 0.68 (#) | 2.5 ± 0.57 (#) |
| Stretching (frequency) | 1.86 ± 0.63 (∗) | 1.86 ± 0.63 | 1.87 ± 0.35 (∗) | 0.5 ± 0.27 | 2.12 ± 0.77 (∗) | 2.43 ± 0.48 | 1.5 ± 0.60 (∗) | 1.62 ± 0.98 |
| EPM | ||||||||
| Stretching(open, closed arms) | 0.63 ± 0.26,3.88 ± 0.30 | 2.63 ± 0.68 (&),2.75 ± 0.70 | 1.13 ± 0.58,3.13 ± 0.50 | 0.75 ± 0.25, 3.50 ± 0.87 | ||||
| Sniffing(center, open, closed arms) | 3.62 ± 0.78, 4.87+/1.14, 13.00 ± 1.85 (∗) | 2.87 ± 0.61, 4.13+/1.11, 9.25 ± 1.77 | 1.5 ± 0.65, 2.75+/1.21, 14.88 ± 2.75 (∗) | 8.38 ± 2.51 4.00+/1.49, 8.38 ± 2.51 | ||||
| Assessment of sedative effects of ethanol and BELs | ||||||||
| Sleep time (s) | 8845.34 ± 736.44 | 9223.57 ± 835.85 | 8327.96 ± 514.17 | 9189.50 ± 173.91 | ||||
| Loss of righting reflex (s) | 916.83 ± 596.99 | 166.00 ± 9.18 | 144.6 ± 9.57 | 213.90 ± 21.07 | ||||
| Blood ethanol levels (mg%) | 360.46 ± 30.56 | 415.32 ± 20.01 | 308.42 ± 30.83 | 358.65 ± 30.73 | ||||
The animals, male or female Wistar rats, were exposed or not to maternal separation on PDs 1–21 and housed under environmental enrichment or standard (control) housing conditions on PDs 21–42. Tests were conducted at PD42 (EPM, LDB) or PD52 (ethanol-induced sedation and hypnosis). The pound sign (#) indicates a significant main effect of Sex on the number of transfers between sectors and on the time spent in the bright sector (LDB test). The asterisk sign (∗) indicates a significant main effect of Rearing conditions during infancy on frequency of stretching (LDB test) and on sniffing (closed arms, EPM test). The ampersand sign (&) indicates that AFR-EE animals made significantly more stretching in the open arms (EPM test) than the rest of the groups.