Kidney histopathology in aspirin + Li-treated rats. Rats were fed regular food (control) or lithium-containing food [LLD-Li or STD-Li] for 42 days. Low-dose aspirin (1 mg/kg, ip) was given alone or together with lithium. On day 42, rats were euthanized, kidneys excised, and longitudinally sectioned in half. Then, 2 μm sections were cut, stained with hematoxylin and eosin, and with Periodic acid–Schiff (PAS) and examined as described in Materials and Methods. Hematoxylin and eosin (A1–F1) and PAS stain (A2–F2) × 100 magnifications. Six samples from each group were randomly chosen for assessment. A1,2—Control, B1,2—LLD-Li, C1,2—STD-Li, D1,2—Aspirin, E1,2—LLD-Li + aspirin, F1,2—STD-Li + aspirin. Abbreviations: ASA—acetylsalicylic acid, LLD—low-low dose, Li—lithium, STD—standard dose. No discernible differences were found among the groups.