(A) Growth-arrested hNPECs were preincubated with sorbinil, zopolrestat or carrier for 24 h followed by treatment with LPS (1 μg/ml) and incubation for different time periods as indicated. At the end of incubation, cells were lysed and equal amount of protein (40 μg) was separated on SDS-PAGE followed by immunoblotting using antibodies against phospho- and total p38, ERK1/2, and SAPK/JNK. Immunoblotting of the stripped membranes with GAPDH antibodies was used to depict equal protein loading. (B) Growth-arrested hNPECs were preincubated with zopolrestat for 24 h followed by treatment with LPS (1 μg/ml) for different durations as indicated. At the end of incubation, cells were harvested, cell membrane fraction was prepared and equal amount of protein (15 μg) was separated on SDS-PAGE followed by immunoblotting using antibodies against phospho- PLCβ3 and -PKC-βII. Immunoblotting of the stripped membranes with antibodies against pan-cadherin was performed to show equal loading of protein (n=3). zopol, zopolrestat.