Fig. 4From: Neuroinflammation is induced by tongue-instilled ZnO nanoparticles via the Ca2+-dependent NF-κB and MAPK pathwaysThe HE stains evaluation of the lingues in rats. a background group; b DW instillation group; c ZnO NPs tongue instillation group; d DW gavage group; e ZnO NPs gavage group. There were no apparent changes in lingual structures in each group, while fungiform papilla hyperemia was observed in ZnO tongue instillation group. The yellow arrow showed fungiform papilla hyperemia. (n = 6). Abbreviations: ZnO: zinc oxide nanoparticles; HE: hematoxylin & eosin; DW: distilled waterBack to article page