Table 4. Effect of Cerebral Blood Flow on Brain-to-Blood (Kb,brain) and Brain-to-Plasma (Kp,brain) Concentration Ratios Determined at 25 min after Injection of (R)-[11C]Verapamil and [11C]-N-Desmethyl-loperamide in Wild-Type FVB/N and Abcb1a/1b(−/−) Micea.
| isoflurane |
awake |
|||||
|---|---|---|---|---|---|---|
| wild-type | Abcb1a/1b(−/−) | fold increase | wild-type | Abcb1a/1b(−/−) | fold increase | |
| (R)-[11C]Verapamil | ||||||
| n | 4 | 4 | 4 | 4 | ||
| Kb,brain | 0.49 ± 0.11 | 2.60 ± 0.37 | 5.3 | 0.53 ± 0.04 | 2.77 ± 0.26 | 5.2 |
| Kp,brain | 0.35 ± 0.09 | 1.91 ± 0.21 | 5.4 | 0.38 ± 0.03 | 2.15 ± 0.18 | 5.7 |
| [11C]-N-Desmethyl-loperamide | ||||||
| n | 3 | 4 | 5 | 6 | ||
| Kb,brain | 0.25 ± 0.06 | 1.42 ± 0.4 | 5.7 | 0.21 ± 0.05 | 2.84 ± 0.14b | 13.8 |
| Kp,brain | 0.20 ± 0.04 | 1.21 ± 0.41 | 6.0 | 0.20 ± 0.05 | 2.79 ± 0.20b | 13.7 |
| N-Isopropyl-p-[125I]iodo-amphetamine | ||||||
| n | 4 | 4 | ||||
| Kb,brain | 12.2 ± 0.4 | nd | nd | 7.5 ± 0.8b | nd | nd |
a
Relative cerebral blood flow was assessed by measurement of Kb,brain of N-isopropyl-p-[125I]iodoamphetamine at 5 min after iv injection under otherwise identical experimental conditions. All data are given as mean ± SD; nd = not determined.
b
P < 0.001 when compared to corresponding isoflurane group (2-tailed t-test).