Comparison of tissue cytochrome P450 3A concentrations in naive, saline and fentanyl pump-implanted PND9 animals
| Tissue | Naive | Saline Pump | Fentanyl Pump |
|---|---|---|---|
| Liver | 1.80 ± 0.25 | 2.91 ± 0.60 | 3.32 ± 0.96 |
| Brain | 6.41 ± 1.92 | 3.31 ± 0.15 | 4.39 ± 0.82 |
Microsomal membranes were prepared, and the concentration of P450 3A was measured by an ELISA assay as detailed under “Methods.” The data are expressed as nanograms of P450 3A per mg protein ± S.E.