Inhibit Histone Deacetylase Type 2 to Improve Memory?

Histone deacetylase (HDAC) enzymes repress gene activation and are thought to modulate plasticity (i.e., brain changes that result from experience), thereby affecting synaptic function and memory formation. To learn more about the role of HDAC enzymes in memory, researchers used behavioral tests in mice that were overexpressing HDAC type 2 (HDAC2-OE) or type 1 (HDAC1-OE), mice with HDAC2 or HDAC1 knocked out (KO), and normal mice.

Compared with normal mice, HDAC2-OE mice did not “learn” to be afraid (i.e., showed markedly less freezing behavior in Pavlovian fear conditioning and significantly greater escape latency in the Morris water maze). In contrast, HDAC2-KO mice had markedly better spatial memory than normal mice. In separate tests, th…