Effects of the combined AMPK and MAPK inhibitors on PC12 and CL1-0 cell survival after ALA-PDT. In the presence of AMPK and MAPK inhibitors, PC12 and CL1-0 cells were treated with 1 mM ALA for 3 hr and then irradiated under the light dose of 2 and 12 J/cm2, respectively. Cell survival was analyzed by Trypan Blue exclusion assay 24 hr post ALA-PDT. Effects of AMPK (Compound C, 40 μM), JNK (SP600125, 40 μM) and p38 (SB203580, 40 μM) inhibitors on ALA-PDT induced cell death were analyzed in PC12 (A) and CL1-0 (B) cells. Results are representative of three independent experiments and are shown as mean ± SD. Significantly different from ALA-PDT with Compound C, SP or SB; *P < 0.05, **P < 0.01.