FIGURE 6.

Effect of ISP1 on sphingolipid biosynthesis in KLA-treated RAW264.7 cells. RAW264.7 cells were incubated for 24 h with vehicle control (PBS), KLA (100 ng/ml), ISP1 (1 μm), or KLA + ISP1. For cells treated with KLA + ISP1, ISP1 was added 1 h prior to the addition of KLA. Following treatment, cells were harvested for lipid extraction and analysis by LC ESI-MS/MS. A, change in the amounts of Cer, HexCer, and SM for cells treated with KLA or KLA + ISP1. Data represent the means ± S.E. (n = 3). B, amounts of the major chain length subspecies of ceramide in cells treated with KLA + ISP1. Data represent the means (n = 3).