Fig. 2

Representative sections of liver tissue of brown trout fry: A–C: control fish, D–F: fish exposed to 100 µg/L metformin. The controls showed large hepatocytes with high amounts of glycogen (stained with alcian blue-PAS in section C). Livers of fish exposed to metformin showed small hepatocytes with low glycogen amount (low staining intensity with alcian blue-PAS in section F). Sections A, B, D and E were stained with haematoxylin–eosin