New rat model for attention deficit hyperactive disorder (ADHD)

作者：Kamimura E; Ueno Y; Tanaka S; Sawa H; Yoshioka M; Ueno K; Inoue T; Li XB; Koyama T; Ishikawa R; Nagashima K^*

来源：Comparative Medicine, 2001, 51(3): 245-251.

Purpose: In a strain of the Long-Evans Cinnamon (LEC) rats, we found spontaneously hyperactive animals designated as "wiggling," and established a congenic wiggling (Wig) rat by transferring the gene from the LEC to the Wistar King-Aptekman/Hokkaido (WKAH) strain. We evaluated the feasibility of the Wig rat for an animal model of human attention deficit hyperactive disorder (ADHD).
Methods: Mode of inheritance was examined by use of linkage analyses. Motor activity, behavior, and working memory were assessed by use of electric digital counters, open field test, and Y-maze and water-maze tests.
Results: The abnormal behavior, including hyperactivity, was transmitted in autosomal recessive mode. Diurnal and nocturnal motor activity of 12- to 14-week-old Wig rats was markedly higher than that of controls, and this hyperactivity was more prominent during nighttime than daytime. Ambulation in the open-field test was significantly increased in Wig rats, but rearing was decreased in Wig rats, compared with controls. Results of the Y-maze tests indicated that spontaneous alternation behavior was significantly impaired in Wig rats, although there was no difference in the total arm entries. The water-maze test could not be performed because, when exposed to water, Wig rats panicked and almost drowned.
Conclusions: Wig rats are hyperactive and have impaired working memory and impulsive behavior, as assessed by the motor activity and open-field tests and the Y-maze test, and these abnormalities are transmitted by a single gene with Mendelian pattern. Wig rats represent an excellent animal model of human ADHD.

• 出版日期2001-6