Effects of IL-6 and GM-CSF on phosphorylation of MAPKs in BMECs. BMECs were exposed to IL-6 (100 ng/mL) or GM-CSF (100 ng/mL) for 4 hr. Western blot analyses were performed to detect phosphorylated p44/42 MAPK (A), p38 MAPK (B), and JNK (C) as well as total p44/42 MAPK, p38 MAPK, and JNK. Relative intensity is calculated as ratio of arbitrary densitometric units of phoshorylated protein to that of total protein. (C) For phospho-JNK, sorbitol-treated PC12 cells were used as positive control (data not shown). Results are expressed % of control. Values are means ± SEM (n = 3-4). Photographs are representative in three to four independent experiments.