Fig. 1. Cell death after polyethylene glycol (PEG) application to acrolein-treated PC12 cells. (A–C) Control PC12 cells are shown developing on the culture substrate. Notice that these cells were well attached and some have extended processes giving them a stellate appearance. (A') The same culture as in A, 4 h after a `sham treatment' – the introduction of PBS into the culture medium. Notice that all cells in this field of view are healthy, developing and all together similar to the culture 4 h previously. (B') The same culture as in B, 4 h after the introduction of 100 µmol l^–1 acrolein. Note the significant loss of cells with cell debris littering the substrate. (C') The same culture as in C, showing significant cell death as a result of acrolein treatment, in spite of the addition of 10 mmol l^–1 PEG to the culture medium within 15 min after acrolein.