Differential effects of age on motor performance in two mouse strains.
The performance of male A/J and C57BL/6J mice from three age groups (4, 18, and 24 months) was observed in a battery of tests designed to assess age-related impairments in motor abilities. A/J mice were superior to C57BL/6J mice in tasks requiring upper body strength, such as tests of grip strength and tightrope performance. C57BL/6J mice were superior performers in tasks requiring balance and coordination, such as movement on stationary and rotating rods. In addition, the C57BL/6J strain generally exhibited greater locomotor activity, such as measured in open field and wheel-running tests. Significant age-related deficits were observe among A/J mice in tests of grip strength, balance rod, rotorod, and wheel activity; and among C57BL/6J mice, in balance, rod, tightrope, exploratory activity, and wheel activity tests. Except for scores of exploratory activity (free versus forced exploration), the test measures tended to be uncorrelated; however, the degree and magnitude of intercorrelation among test scores increased with age. The results underscore the need to consider genotype in the assessment of age-related motor impairments in animal models.
D000375:Aging; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D005106:Exploratory Behavior / Q000502:physiology; D005838:Genotype; D008297:Male; D051379:Mice; D008805:Mice, Inbred A; D008810:Mice, Inbred C57BL; D009043:Motor Activity / Q000502:physiology*