Age-related changes in the motricity of the inbred mice strains 129/sv and C57BL/6j.
The development of motor skills was studied at different stages in the life of the mouse, focusing on three key aspects of motor development: early rhythmic motor activities prior to the acquisition of quadruped locomotion, motor skills in young adults, and the effect of aging on motor skills. The age-related development pattern was analysed and compared in two strains of major importance for genomic studies (C57Bl6/j and 129/sv). Early rhythmic air-stepping activities by l-dopa injected mice showed similar overall development in both strains; differences were observed with greater beating frequency and less inter-limb coordination in 129/sv, suggesting that 129/sv had a different maturation process. Performance on the rotarod by young adult C57Bl6/j gradually improved between 1 and 3 months, but then declined with age; performance on the treadmill also declined with an age-related increase in fatigability. Overall performance by 129/sv mice was lower than C57Bl6/j, and the age-related pattern of change was different, with 129/sv having relatively stable performance over time. Inter-strain differences and their possible causes, in particular the role of dopaminergic pathways, are discussed together with repercussions affecting mutant phenotyping procedures.
Serradj
Najet
N
CNRS, GFCP/P3M, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France. serradj@dpm.cnrs-mrs.fr
Jamon
Marc
M
D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008817:Mice, Mutant Strains; D009043:Motor Activity / Q000235:genetics; D009048:Motor Skills / Q000502:physiology*; D010507:Periodicity; D045442:Rotarod Performance Test / Q000379:methods; D013045:Species Specificity; D013997:Time Factors