Neurological Effects of Combining Low Toxic Dose of Tramadol and Nicotine: An Animal Model Evidence of Endoplasmic Reticulum Stress

Figure 4

Immunohistochemical staining sections of the brain cortex of six groups showing positive cytoplasmic expression of CHOP antibodies in all groups, including G6 (normal control). Negative expression of caspase-8 antibodies in all groups except mild expression in G4 (nicotine) and G1 (high-dose tramadol). P53 is expressed in all groups with the lowest positivity in G3 (nicotine+tramadol) and G6 (normal control) (×400 all).