Table 2.
Effects of chronic administration of kynurenine metabolites on concentrations of tryptophan and kynurenines in rat liver.
| PARAMETER | LIVER | SERUM | ||||||
|---|---|---|---|---|---|---|---|---|
| CONTROL | KA | 3-HK | 3-HAA | CONTROL | KA | 3-HK | 3-HAA | |
| Trp | 21.2 ± 1.8 | 20.7 ± 0.9 | 19.2 ± 1.3 | 17.0 ± 0.9 | 75 ± 4 | 68 ± 4 | 66 ± 4 | 63 ± 2* |
| K | 5.4 ± 0.3 | 6.3 ± 0.1* | 9.5 ± 0.8* | 3.6 ± 0.8* | 5.8 ± 0.5 | 5.5 ± 0.6 | 6.2 ± 0.6 | 10.9 ± 0.9* |
| KA | 4.3 ± 0.2 | 10.6 ± 0.9* | 4.4 ± 0.5 | 2.7 ± 0.4* | 0.8 ± 0.1 | 3.8 ± 0.8* | 0.23 ± 0.03* | 0.10 ± 0.04* |
| AA | 3.0 ± 0.1 | 3.4 ± 0.3 | 0.8 ± 0.1* | 5.0 ± 0.5 | 3.7 ± 0.8 | 5.1 ± 0.2 | 4.3 ± 0.1 | 3.7 ± 0.1 |
| 3-HK | 4.8 ± 0.3 | 5.6 ± 0.3 | 18.6 ± 1.7* | 14.1 ± 2.2* | 7.2 ± 0.7 | 7.5 ± 0.8 | 17.3 ± 2.2* | 8.7 ± 1.5 |
| XA | 0.02 ± 0.01 | 0.04 ± 0.02 | 1.1 ± 0.2* | 1.4 ± 0.2* | 2.1 ± 0.4 | 2.6 ± 0.2 | 4.8 ± 1.1* | 2.5 ± 0.3 |
| 3-HAA | 4.9 ± 0.4 | 5.2 ± 0.5 | 7.5 ± 1.3 | 10.3 ± 0.3* | 0.05 ± 0.01 | 0.06 ± 0.02 | 4.9 ± 1.1* | 11.0 ± 1.7* |
Notes: Rats were treated intraperitoneally once daily for 8 days with saline or a 10 mg/kg dose of kynurenine metabolites and were killed at 2 hours after the injection on the final day. Values in μM are mean ± SEM for six rats per group. The asterisk (*) denotes a significant difference from controls at P levels of 0.044–0.001.