Effect of various molybdenum hydroxylases inhibitors on formation of 5-oxo-Zaleplon in monkey liver cytosol
| Inhibitor | Target Enzyme | Inhibitor concentration | 5-Oxo-Zaleplon Formed (% of control)1-a |
|---|---|---|---|
| Monkey liver cytosol | |||
| mM | |||
| CO | 80% (v/v) CO/O2 | 92.9 ± 4.3 | |
| KCN | XD/XO, AO | 1 | N.D.1-b |
| Allopurinol | XD/XO | 0.1 | 85.1 ± 0.9 |
| Oxipurinol | XD/XO | 0.1 | 92.9 ± 2.5 |
| Methotrexate | XD/XO | 0.1 | 96.7 ± 1.5 |
| Quinacrine | AO | 0.1 | 50.0 ± 5.7 |
| Menadione | AO | 0.1 | 6.5 ± 1.2 |
| SKF 525-A | AO | 0.1 | 65.4 ± 1.5 |
↵1-a Data are expressed as mean ± S.D. of triplicate determinations and as percentage of remaining activity. Zaleplon (50 μM) was incubated at 37°C for 10 min (20 min for CO as the inhibitors) with monkey liver cytosol (20 mg liver/ml) and EDTA (0.1 mM) in 0.1 M phosphate buffer (pH7.4), as described in Materials and Methods. The control formed 5-oxo-Zaleplon at a rate of 20.16 ± 0.42 nmol/g liver/ml.
↵1-b N.D., not detected (<0.56 nmol/g liver/ml).