Table 1.
Effect of genetic depletion of prodynorphin on MA-induced changes in activity in enzymatic antioxidants
| A | ||||||||
| SOD (units/mg protein) | Saline | MA | ||||||
| 1 h | 3 h | 6 h | 12 h | 1 day | 3 days | |||
| Dorsal striatum | WT | 6.1 ± 0.6 | 7.5 ± 0.5† | 8.4 ± 0.7*’‡ | 12 ± 0.4**‡ | 11.1 ± 0.8**‡ | 10.0 ± 0.3**‡ | 6.5 ± 0.4 |
| DYN KO | 6.0 ± 0.3 | – | – | 15.5 ± 0.7**,# | – | 12.9 ± 0.3**,# | – | |
| NAc | WT | 5.0 ± 0.3 | 5.6 ± 0.5 | 6.7 ± 0.3* | 6.3 ± 0.3** | 7.1 ± 0.6* | 6.8 ± 0.4* | 5.7 ± 0.4 |
| DYN KO | 4.8 ± 0.4 | – | – | 11.1 ± 0.5**,# | – | 9.1 ± 0.5**,# | – | |
| Ventral midbrain | WT | 5.8 ± 0.4 | 6.5 ± 0.4 | 7.4 ± 0.3*,& | 9.7 ± 0.6**,& | 8.4 ± 0.5**,& | 7.9 ± 0.4**,& | 6.3 ± 0.5 |
| DYN KO | 5.9 ± 0.6 | – | – | 12 ± 0.6**,# | – | 10.2 + 0.4 | – | |
| B | ||||||||
| Catalase (units/mg protein) | Saline | MA | ||||||
| 1 h | 3 h | 6 h | 12 h | 1 day | 3 days | |||
| Dorsal striatum | WT | 1.7 ± 0.09 | 2.0 ± 0.16† | 2.1 ± 0.07*,† | 2.4 ± 0.14**,† | 2.6 ± 0.19**,‡ | 2.5 ± 0.13**,‡ | 1.9 ± 0.09 |
| DYN KO | 1.6 ± 0.08 | – | – | 2.4 ± 0.06** | – | 2.2 ± 0.08* | – | |
| NAc | WT | 1.4 ± 0.06& | 1.5 ± 0.1 | 1.6 ± 0.08* | 1.7 ± 0.08 | 1.9 ± 0.06** | 1.8 ± 0.11* | 1.6 ± 0.07* |
| DYN KO | 1.2 ± 0.05 | – | – | 1.8 ± 0.08* | – | 1.6 ± 0.09* | – | |
| Ventral midbrain | WT | 1.6 ± 0.09 | 1.7 ± 0.32 | 1.8 ± 0.12 | 1.9 ± 0.09* | 2.2 ± 0.13**,& | 2.1 ± 0.11**,& | 1.8 ± 0.09 |
| DYN KO | 1.3 ± 0.07 | – | – | 2 ± 0.09* | – | 1.8 ± 0.09* | – | |
| C | ||||||||
| GPx (nmole NADPH/min/mg protein) | Saline | MA | ||||||
| 1 h | 3 h | 6 h | 12 h | 1 day | 3 days | |||
| Dorsal striatum | WT | 9.9 + 0.3 | 8.5 ± 0.8 | 7.4 ± 0.4* | 4.9 ± 0.5**,† | 5.4 ± 0.3**,† | 5.6 ± 0.4**,† | 8.4 ± 0.6 |
| DYN KO | 9.3 ± 0.5 | – | – | 3.9 ± 0.5**,# | – | 5.3 ± 0.4**,# | – | |
| NAc | WT | 8.7 ± 0.4 | 8.3 ± 0.3 | 7.3 ± 0.3* | 6.3 ± 0.3** | 6.7 ± 0.2** | 7.1 ± 0.5** | 8.3 ± 0.2 |
| DYN KO | 8.2 ± 0.4 | – | – | 4.9 ± 0.3**,# | – | 6.1 ± 0.4**,# | – | |
| Ventral midbrain | WT | 9.2 ± 0.6 | 8.7 ± 0.3 | 7.8 ± 0.5* | 6.7 ± 0.3** | 6.7 ± 0.5** | 7.0 ± 0.4** | 8.6 ± 0.3 |
| DYN KO | 8.9 ± 0.4 | – | – | 5.1 ± 0.5**,# | – | 6.3 ± 0.5**,# | – | |
SOD superoxide dismutase, GPx glutathione peroxidase, Sal saline, MA methamphetamine 35 mg/kg, i.p, WT wild-type mice, DYN KO prodynorphin knockout mice. Each value is the mean ± SEM of six animals [two-way ANOVA (time points × brain regions) followed by Fisher’s LSD pairwise comparisons. Additional two-way ANOVA (time points × gene) with Fisher’s LSD pairwise comparisons was done to examine the effect of DYN KO 6 h and 1 day after MA]. *p < 0.05,**p < 0.01 vs. corresponding Saline.#p < 0.05,##p < 0.01 vs. corresponding MA/WT. †p < 0.05, ‡p < 0.01 vs. corresponding NAc or ventral midbrain. &p < 0.05 vs. corresponding NAc