In the two epilepsy models above, the increases in c-fos, c-jun, and brain-derived neurotrophic factor (BDNF) expression were attributed to the decreased expression of class I HDACs, the increased phosphorylation of histone H3, and the excessive acetylation of histone H4 in rat hippocampal neurons [126,130,131]. Here, JUN is linked to epilepsy.