TY - JOUR AU1 - Masuo, Yoshinori AU2 - Ishido, Masami AU3 - Morita, Masatoshi AU4 - Sawa, Hirofumi AU5 - Nagashima, Kazuo AU6 - Niki, Etsuo AB - Recently, congenic wiggling (Wig) rats were described as a good model for attention‐deficit hyperactivity disorder; 12‐ to 14‐week‐old animals demonstrated hyperactivity, impulsive behaviour and an impaired working memory. Here, we show that 4‐ to 5‐week‐old Wig rats displayed significantly greater spontaneous motor activity than control rats during a period of darkness. Subcutaneous injection of 4 mg/kg methamphetamine exacerbated hyperactivity, the reverse of its effect in rats with neonatally induced 6‐hydroxydopamine lesions. Immunohistochemistry showed low levels of tyrosine hydroxylase in the ventral midbrain, similar to 6‐hydroxydopamine‐treated rats. In cDNA macroarrays, 4‐week‐old Wig rats showed increased expression of the adenosine A2a receptor in the dorsal striatum, macrophage migration inhibitory factor in the frontal cortex, ventral striatum and midbrain, and calbindin 2 in the dorsal and ventral midbrain. Expression of the γ‐aminobutyric acid (GABA) transporter and sterol carrier protein 2 genes was reduced in all regions. Dopamine transporter gene expression was increased in the dorsal midbrain but decreased in the ventral midbrain, a pattern distinct from that induced by 6‐hydroxydopamine. Although abnormal development of dopaminergic neurons may underlie motor hyperactivity, other mechanisms may control responsiveness to methamphetamine. Wig rats may provide a model of attention‐deficit hyperactivity disorder in which treatment with psychostimulants accelerate the hyperactivity. TI - Behavioural characteristics and gene expression in the hyperactive wiggling (Wig) rat JF - European Journal of Neuroscience DO - 10.1111/j.1460-9568.2007.05613.x DA - 2007-06-01 UR - https://www.deepdyve.com/lp/wiley/behavioural-characteristics-and-gene-expression-in-the-hyperactive-WlBla1nMIP SP - 3659 VL - 25 IS - 12 DP - DeepDyve ER -