Expression of HIF-1α, ARNT1, and ARNT2 but not HNF4α in SH-SY5Y cells.

Western blot analyses of nuclear extracts (20 μg) and whole-cell lysates (75 μg) from SH-SY5Y and HepG2 cells exposed to normoxia (N), hypoxia (H), and anoxia (A) for 4 hours were performed with antibodies against HIF-1α, ARNT1, ARNT2, and HNF4α. Antibodies against histone H1 and α-tubulin were used as loading controls for nuclear extracts and total-cell lysates, respectively.