Histological studies on developing chick embryos treated with aminoguanidine sulfate.

Fertile eggs were injected 10 or 20 mg/egg of aminoguanidine sulfate (AGS) into the albumen on the 5th day of incubation and examined macroscopically and histopathologically. The marked abnormalities were observed in liver, gallbladder and spleen while other organs were not different from the control. The earliest change was an increase of mitotic cells in the liver which reached to the peak at 2 days after the AGS injection. The increase of the ratio of cells in metaphase was characteristic. Decrease of weight, retardation of the development, fatty degeneration, necrosis and increase of connective tissues in the liver were followed. The abnormality of gallbladder such as aplasia and hypoplasia was observed with high frequency. Spleens of the AGS-treated group were enlarged from the 16th day of incubation. The clearest change of spleen was fatty degeneration.