Influence of dystrophin-gene mutation onmdx mouse behavior. I. Retention deficits at long delays in spontaneous alternation and bar-pressing tasks

Abstract

X-linked Duchenne muscular dystrophy (DMD) is frequently associated with a nonprogressive, cognitive defect attributed to the absence of dystrophin in the brain of DMD patients. The mutant mdx mouse, lacking in 427-kDa dystrophin in both muscle and brain tissues, is considered to be a valuable model of human DMD. In the present study, we compared mdx and C57BL/10 control mice and showed that mdx mice had impaired retention in a T-maze, delayed spontaneous alternation task 24 h, but not 6 h, after acquisition. mdx mice were not impaired in acquisition of a bar-pressing task on 4 consecutive days but showed poor retention 22 days after the last training session. Mutants and controls showed similar behavioral responses in free exploration and light/dark choice situations and did not differ in spontaneous locomotor activity or motor coordination. Retention impairments at long delays in mdx mice suggest a role of dystrophin in long-term consolidation processes.

Cortical and brainstem neurons containing calcium‐binding proteins in a murine model of Duchenne's muscular dystrophy: Selective changes in the sensorimotor cortex

“…Likewise, behavioral studies on mdx mice demonstrated retention impairments at long delays, suggesting a role for dystrophin in long-term consolidation processes (Vaillend et al, 1995(Vaillend et al, , 1998. Together with our findings on structural CNS alterations, the latter data move the focus of DMD pathogenesis toward the brain as the primary target of interest for future investigation on the effects of dystrophin deficiency.…”

Spaceflight results in increase of thick filament but not thin filament proteins in the paramyosin mutant of Caenorhabditis elegans

“…The model animal of muscular dystrophy, mdx mouse, shows little clinical signs and no neurological signs of muscular dystrophy up to an age of 18 months, in spite of a nonsense mutation in the dystrophin gene (Sicinski et al, 1989;Vaillend et al, 1995).…”

Evidence ofmdx mouse skeletal muscle fragility in vivo by eccentric running exercise

“…The mdx mouse lacks subsarcolemmal Dys because of a mutation in position 3185 of the Dys gene. 41 Despite this lack of Dys, adult mdx mice show little clinical signs and no neurological signs 44 of Duchenne dystrophy up to 18 months. Actually, the evolution of the disease seems to be roughly triphasic in this model, and the muscle histology and phenotype of the mouse depend on its age.…”