IImmunostaining of histological sections of livers of rats with bax antibodies. A, 3 months old control rat; B, 3 months old quercetin-treated rats; C, 30 months old saline-treated rats; D, 30 months old quercetin-treated rats. Note the rarity of bax expressions (arrows) in A and B then the increase of its expression in C (arrows) then the decrease of its (arrows) expression in D.