Automatic Recording and Analysis of the Ambulatory Dynamics of Cerebellar Ataxic Mice-Rolling Mouse Nagoya, Reeler and Weaver

Rolling mouse Nagoya (Rolling) was found by Dr. Oda, Univ. of Nagoya, in 1969 as a spontaneous mutant and is characterized by the abnormal gait which appears about 2 weeks after birth. The origin and its mechanism of the motor abnormalities of Rolling has not yet been cleared, but this mouse is now grouped to be one of the cerebellar ataxic mice. The locomotion of the adult mice was automatically recorded and quantitized into the counts of each size of movements, and the gait of Rolling was compared with those of the nonaffected normal mouse, Reeler and Weaver. The reproducibility of the locomotion of the mice was fairly good regardless of the cage used and the observation time (less than 10 min.). Affected mice showed significantly small number of counts in size of 1/4 and 1/8 (about 6 and 3 cm in practice) of movements due to toppling during gait compared with the nonaffected normal mice. The gait of Rolling was not completely discerned from the Reeler or Weaver in the spectrum of movements. However, in locus of movements, each mutant showed the specific features of the motor abnormalities. Results presented in this paper suggest that Rolling is similar to Reeler and Weaver with regard to the cerebellar ataxia.