Shati/Nat8l knockout mice show behavioral deficits ameliorated by atomoxetine and methylphenidate

Abstract

We previously identified a novel molecule, SHATI/NAT8L, as having an inhibitory effect on methamphetamine dependence. We generated Shati/Nat8l knockout (KO) mice and found that they showed neurochemical changes and behavioral abnormalities related to attention deficit/hyperactivity disorder (AD/HD). In this study, we assessed validities of the Shati/Nat8l KO mice as a new animal model for AD/HD through a behavioral pharmacology approach. We conducted a locomotor activity test in a novel environment, a cliff avoidance test, and an object-based attention assay using Shati/Nat8l KO mice at the ages of 4 and 8 weeks. We found that at the ages of both 4 and 8 weeks, Shati/Nat8l KO mice showed hyperactivity in locomotor activity test, shortened jumping latency in cliff avoidance test, and lower recognition index in object-based recognition test. Moreover, we evaluated the effects of atomoxetine (ATX) and methylphenidate (MPH) on the behavioral deficits in Shati/Nat8l KO mice. As the result, almost all behavioral deficits were improved by the treatment of both ATX and MPH. Our findings suggest that Shati/Nat8l KO mice have an impaired neural system similar to AD/HD pathophysiology. Shati/Nat8l KO mice might serve as a novel and a useful animal model for the pathophysiology of AD/HD.

Keywords: Atomoxetine; Attention deficit/hyperactivity disorder; Dopamine; Methylphenidate; SHATI/NAT8L.