Valproic Acid-d4 is a deuterated compound of Valproic Acid. Valproic Acid has a CAS number of 99-66-1. Valproic Acid is a branched chain fatty acid which potentially enhances central GABAergic neurotransmission and inhibits Na+ channels. Currently, the various molecular mechanisms of action of Valproic Acid have not been completely elucidated. Valproic Acid has been reported to be a potent inhibitor of histone deacetylases (HDACs) in vitro. Valproic Acid is also noted to relieve HDAC-dependent transcriptional repression and causes the hyperacetylation of histones in cultured cells. Additionally, Valproic Acid is reported to activate Wnt-dependent gene expression and to mimic trichostatin A (sc-3511) in the inhibition of histone deacetylase.