Influence of inhibitors of nSMase [glutathione in its reduced (GSH) and oxidized forms (GSSH)], cPLA2 (AACOCF3), MAPKs (SB203580, PD98059), and SPT (L-cycloserine, ISP-1) on R(+)-MA—induced C16-ceramide formation
Cells were incubated with R(+)-MA (10 μM) or its vehicle for 4 h in the presence of the test substances (1 h preincubation). Values are comparisons with the vehicle-treated cells (100%) in the absence of test substance. Values are means ± S.E.M. of n = 3 to 4 experiments.
| C16-Ceramide | |
|---|---|
| % | |
| Vehicle | 100 ± 23 |
| R(+)-MA (10 μM) | 192 ± 18 |
| R(+)-MA + GSH (1 mM) | 257 ± 26 |
| R(+)-MA + GSSG (1 mM) | 272 ± 62 |
| Vehicle | 100 ± 6 |
| R(+)-MA (10 μM) | 209 ± 15 |
| R(+)-MA + SB203580 (30 μM) | 178 ± 30 |
| R(+)-MA + PD98059 (30 μM) | 200 ± 19 |
| R(+)-MA + AACOCF3 (15 μM) | 293 ± 144 |
| Vehicle | 100 ± 27 |
| R(+)-MA (10 μM) | 201 ± 10 |
| R(+)-MA + L-cycloserine (1 mM) | 223 ± 21 |
| R(+)-MA + ISP-1 (10 μM) | 213 ± 26 |