The expression of Cat C was induced in the brain at six hours and twenty-four hours following LPS injection. IHC double staining showed that the Cat C expression was induced in cortical neurons at six hours after LPS injection (A to C). After LPS injection for twenty-four hours, the expression of Cat C mRNA and protein was induced further and distributed throughout the entire brain, such as the cortex (D and G), hippocampus (E and H) and SN (F and I). Double staining of Iba-1 (IHC) and Cat C (ISH) showed that Cat C expression was induced in microglial cells at twenty-four hours after LPS injection (J and K). Scale bar = 20 μm (A to C, J and K); 50 μm (D to I). n = 5 per condition. Cat C, cathepsin C; Iba-1, ionized calcium binding adaptor molecule-1; IHC, immunohistochemistry; ISH, in situ hybridization; LPS, lipopolysaccharide. SN, substantia nigra.