Table 2.
The effects of chronic administration of salsolinol on l-DOPA-induced changes on dopamine metabolism in rat brain structures
| Treatment | DA (ng/g tissue) | DOPAC (ng/g tissue) | HVA (ng/g tissue) | [HVA]/[DA] × 100 | |
|---|---|---|---|---|---|
| Chronic | Acute | ||||
| Substantia nigra | |||||
| Saline | Saline | 844 ± 61 | 215 ± 18 | 152 ± 11 | 18 ± 2 |
| Saline | l-DOPA 100 | 4775 ± 898** | 19,039 ± 3135** | 9133 ± 622** | 249 ± 60** |
| Salsolinol 100 | Saline | 913 ± 59 | 198 ± 14 | 146 ± 14 | 16 ± 1 |
| Salsolinol 100 | l-DOPA 100 | 2996 ± 623*+ | 5372 ± 4089**+ | 9256 ± 1008** | 337 ± 87** |
| Effect of salsolinol |
F (1/24) = 2.4 N.S. |
F (1/24) = 0.5 N.S. |
F (1/24) = 0.01 N.S. |
F (1/24) = 0.6 N.S. |
|
| Effect of l-DOPA |
F (1/24) = 30.1 P < 0.01 |
F (1/24) = 43.5 P < 0.01 |
F (1/24) = 233 P < 0.01 |
F (1/24) = 26.9 P < 0.01 |
|
| Interaction of salsolinol + l-DOPA |
F (1/24) = 2.8 N.S. |
F (1/24) = 0.5 N.S. |
F (1/24) = 0.01 N.S. |
F (1/24) = 0.7 N.S. |
|
| Striatum | |||||
| Saline | Saline | 10,439 ± 308 | 1467 ± 49 | 1149 ± 31 | 11 ± 0.5 |
| Saline | l-DOPA 100 | 21,031 ± 2530** | 28,780 ± 3700** | 14,858 ± 719** | 77 ± 10** |
| Salsolinol 100 | Saline | 11,415 ± 394 | 1789 ± 124 | 1377 ± 112 | 12 ± 0.8 |
| Salsolinol 100 | l-DOPA 100 | 16,145 ± 1655*+ | 24,479 ± 5854** | 16,492 ± 1180** | 106 ± 10**++ |
| Effect of salsolinol |
F (1/24) = 1.6 N.S. |
F (1/24) = 0.3 N.S. |
F (1/24) = 1.8 N.S. |
F (1/24) = 4.5 P < 0.05 |
|
| Effect of l-DOPA |
F (1/24) = 25 P < 0.01 |
F (1/24) = 52.1 P < 0.01 |
F (1/24) = 432 P < 0.01 |
F (1/24) = 128 P < 0.01 |
|
| Interaction of salsolinol + l-DOPA |
F (1/24) = 3.6 N.S. |
F (1/24) = 0.4 N.S. |
F (1/24) = 1.0 N.S. |
F (1/24) = 3.9 N.S |
|
Salsolinol was administered (100 mg/kg i.p.) chronically for 14 consecutive days. In the combined treatment group, l-DOPA (100 mg/kg i.p.) was administered once 15 min after the final salsolinol administration. The rats were decapitated 2 h after the final injection. The concentration of dopamine and its metabolites were measured using HPLC. The results are expressed as the means ± SEM of seven samples (n = 7 animals per group). The data were analyzed via two-way ANOVA followed by Duncan’s test. Statistical significance: * P < 0.05, ** P < 0.01 versus the control group; + P < 0.05, ++ P < 0.01 versus the l-DOPA group