Ataxic gait analysis in a mouse model of the olivocerebellar degeneration

Lurcher mutant mice represent a model of olivocerebellar degeneration. Postnatally, a complete loss of Purkinje cells and secondary reduction of granule cells and inferior olive neurons occurs. Cerebellar ataxia is among the symptoms of degeneration of the cerebellum. The aim of the work was to identify gait parameters which are changed in Lurcher mice due to cerebellar ataxia arising from functional cerebellar decortication, and to assess the correlation between gait parameters, walking speed and performance in rotarod test. We used the adult Lurcher mutant and wild type mice of the B6CBA strain. For gait analysis the CatWalk system was used. Motor functions were examined with the rotarod. Data analysis revealed significant differences between Lurchers and controls in many gait parameters. However, almost all parameters correlated with the walking speed and the differences disappeared after the correction to the walking speed. The question is what is the primary change in Lurchers-whether the walking speed or individual gait parameters. In the rotarod test, the Lurcher mutants revealed significantly worse results than the wild type animals. No correlation between the gait parameters and performance in the rotarod test was found.