Fig. 2. The effect of heme deficiency on NGF-induced PC12 cell neuronal differentiation. PC12 cells were treated with no reagent (None), or succinyl acetone alone (SA), or NGF alone (NGF), or NGF and succinyl acetone (NGF+SA), or NGF and heme and succinyl acetone (NGF+SA+heme) for 10 days. Scale bar, 100 µm.