Effect of L-Cysteine on phospho-eIF2α, ATF4, phospho-IRE1 and ATF6 expression. The levels of phospho-eIF2α, ATF4, phospho-IRE1 and ATF6 of the ipsilateral hemisphere were examined 3 days after HI by Western blot. Bar graphs show quantification of the protein levels. Values represent the mean ± SD, n = 3 in each group, ***p < 0.001 HI VS Sham; ##p < 0.01, ###p < 0.001 HI + L-Cys VS HI; & p < 0.05, && p < 0.01 HI + L-Cys +AOAA VS HI + L-Cys.