TABLE 1.
Effect of roxithromycin on NADPH oxidase activity and kinetic constants
| Time of drug addition and parameter | HBSS | 0.3% DMSO | Roxithromycin (100 mg/liter) |
|---|---|---|---|
| After isolation of particulate fractions | |||
| Activitya | 30 ± 4.8 (5)d | 28 ± 3.15 (7) | 30 ± 3.5 (7) |
| Kmb | 95 ± 29.5 (4) | 129 ± 32.2 (7) | 131 ± 29.7 (7) |
| Vmaxc | 42 ± 10.1 (4) | 55 ± 15.4 (4) | 52 ± 9.3 (7) |
| 30 min before stimulation and isolation of particulate fractions | |||
| Activity | 64 ± 19.3 (7) | 48 ± 9.3 (12) | 31 ± 6.4 (12)e |
| Km | 64 ± 10.7 (5) | 115 ± 30.0 (12) | 81 ± 13.8 (12) |
| Vmax | 52 ± 8.4 (5) | 60 ± 7.8 (12) | 39 ± 4.5 (12)e |
a
Nanomoles of cytochrome c reduced/min/mg protein (500 μM NADPH).
b
Km, NADPH, μM.
c
Vmax, nanomoles of cytochrome c reduced/min/mg protein.
d
The number of experiments is in parentheses.
e
Significantly different from control (DMSO solution).