Chronic ethanol exposure increases PKC activity and PKCδ and PKCε protein levels in PC12 cells and in NG-108-15 cells.189 In vivo, chronic ethanol treatment decreases PKC activity in the cortex and hippocampus of rats,190 decreases PKCα and PKCγ levels in the frontal cortex in mice,191 and increases PKCα and PKCγ protein levels in the limbic forebrain in mice.191