Tissue levels of radioactivity (ng/g tissue) in mdrla (+/+) and (−/−) mice at 4 h after i.v. injection of [14C]fexofenadine (1.0 mg/kg)
| Tissue | Fexofenadine i.v. (1 mg/kg) | Fexofenadine Oral (2.6 mg/kg) | ||||
|---|---|---|---|---|---|---|
| Mdrla (+/+) | Mdrla (−/−) | Ratio (−/−)/(+/+) | Mdrla (+/+) | Mdrla (−/−) | Ratio (−/−)/+/+) | |
| Plasma | 4.1 ± 1.9 | 19 ± 4.5** | 4.6 | 2.4 ± 0.82 | 11 ± 1.8** | 4.6 |
| Brain | 0.71 ± 0.48 | 6.3 ± 0.92** | 8.9 | 0.10 ± 0.02 | 0.67 ± 0.27** | 6.7 |
| Heart | 3.1 ± 0.94 | 12 ± 2.6** | 3.9 | 2.0 ± 0.54 | 5.5 ± 1.2* | 2.8 |
| Lung | 41 ± 5.9 | 66 ± 19 | 1.6 | 6.1 ± 3.0 | 17 ± 6.3 | 2.8 |
| Liver | 112 ± 57 | 531 ± 217* | 4.7 | 64 ± 26 | 218 ± 48* | 3.4 |
| Spleen | 3.2 ± 1.2 | 8.7 ± 0.35** | 2.7 | 1.0 ± 0.34 | 5.2 ± 1.0** | 5.2 |
| Kidney | 199 ± 50 | 877 ± 392* | 4.4 | 24 ± 8.3 | 147 ± 37** | 6.1 |
| Small intestine | 58 ± 27 | 346 ± 37** | 5.7 | 129 ± 59 | 135 ± 35 | 1.0 |
| Colon | 148 ± 40 | 339 ± 171 | 2.3 | 55 ± 9.9 | 98 ± 34 | 1.8 |
Data are shown as mean ± S.D. Statistical difference in radioactivity between the two groups of mice was assessed by a two-sided Student’s t test, with p < .05 as the limit of significance (* p < .05,** p < .01).