Figure 5

Effects of intermittent hypoxia (IH)-induced ROS generation on PP2A activation and downregulated ERK1/2 activation leading cell differentiation inhibition by nerve growth factor (NGF)-stimulated PC12 cells. (A) Images of neurite outgrowth using light microscopy and (B) percentages of differentiated cells among NGF-stimulated PC12 cells after 3–4 days of intermittent hypoxia (n = 5 for per group). (C) Percentages of differentiated cells among NGF-stimulated PC12 cells after exposure to normoxia for 4 days (RA4, control, n = 16), RA4 along with U0126 (n = 6) and PD98059 (n = 5) (ERK1/2 phosphorylation inhibitors), and nicotine (n = 10) (ERK1/2 phosphorylation inducer), and exposed to IH for 4 days (IH4, control, n = 14), IH4 along with superoxide dismutase (SOD, n = 8), 1,10-phenanthroline (Phe, n = 9), okadaic acid (OKA, n = 12) and cantharidin (Can, n = 5) (PP2A activation inhibitors), and nicotine (n = 7). *p < 0.05 compared with RA4. ^#p < 0.05 compared with IH4. Values are means ± SEMs.