The present investigation was carried out on forty apparently healthy mature male Westar rats weighing between 120-200 gm with average three months age. The rats wereobtained from laboratory animal unite in the faculty of pharmacy, King Saud University and were divided randomly into four groups (10 rats/ group). Group I (G1) was kept as a control, Group II (G2)was obtained ZnO NPsin a dose 100 mg/kg body weight, Group III(G3)was obtained ZnO NPsin a dose 250 mg/kg BW, Group IV(G4)was obtained ZnO NPsin a dose 500 mg/kg BW and all treated groups received ZnO NPs by oral gavage for 21 days. G1 showed normal histological structure of all hepatic tissues without any abnormalities. G2 and G3 showed mild to moderate steatosis, necrosis with focal scattered of infammatory cells infltration with fibrous tissue proliferation and moderate hepatocytes glycogen depletion. Meanwhile, G4 showed severe steatosis, diffuse degeneration of hepatic tissues with loss of the hepatic architectures, sever fibrous tissue proliferation with anti-inflammatory cells infiltration as well as severe congestion with the hepatic artery, sinusoids and Portal vein. In addition, sever sinusoidal dilatation accompanied by Kupffer cells hyperplasia in between the hepatic cords were clarified. Furthermore, with PAS stain, sever hepatocytes glycogen depletion were claimed. The present investigation was concluded that the ZnO NPs have potential oxidative stress in the hepatic tissues that may affect the function of the liver.
Keywords: Zinc oxide, nanoparticles, hepatotoxicity, histochemical, ZnO NPs