Bovine serum albumin induced endoplasmic reticulum stress in NRK-52E cells.

<p>A. Western blot analysis shows the expression of GRP78 and the phosphorylation of eIF2a in NRK-52E cells after treatment without or with 5 mg/ml BSA for various time periods in serum-free medium. The whole cell lysate was immunoblotted with GRP78, phosphorylated- eIF2α and eIF2α antibody, respectively. The same blot was reprobed with α-tubulin to confirm equal loading of each lane. B. Western blot analysis shows the expression of GRP78 and the phosphorylation of eIF2a in NRK-52E cells without or with different amounts of BSA for 12 h in serum-free medium. C and D: Graphical presentation shows the relative abundances of GRP78 after normalization with α-tubulin and the phosphorylation of eIF2α after normalization with eIF2α. Data are presented as mean±SEM of three independent experiments. *<i>P</i><0.05 vs. normal control (the relative abundance of GRP78 protein level); # P<0.05 vs. normal control (the phosphorylation of eIF2α).