High resolution magnetic resonance imaging of the brain in the dy/dy mouse with merosin-deficient congenital muscular dystrophy.
Magnetic resonance imaging (MRI) abnormalities in the cerebral white matter are a consistent feature of merosin-deficient human congenital muscular dystrophy, a disease caused by a primary defect in the expression of the laminin alpha2 chain of merosin. To investigate the relationship between imaging changes and merosin deficiency we undertook a MRI study in the dy/dy mouse, an animal model for this form of human congenital muscular dystrophy. High resolution in vivo imaging was performed on anaesthetized animals (two homozygous dy/dy mutants and two heterozygous dy/DY controls, aged 2.5 months) in a dedicated 11.7T magnetic resonance imaging scanner. T(1) and T(2) weighted images were normal in all mice and white matter changes were not seen at a stage of maturity when MRI changes are already very striking in human patients. Cerebral MRI abnormalities do not appear to be a feature of dy/dy mice, despite the virtual absence of merosin expression in the dy/dy mouse brain. Possible causes for this absence of MRI changes, and implications for the pathogenesis of the MRI changes in humans are reviewed.
Dubowitz
D J
DJ
Division of Biology 216-76, California Institute of Technology, Pasadena, CA 91125, USA. dubowitz@vis.caltech.edu
Tyszka
J M
JM
Sewry
C A
CA
Moats
R A
RA
Scadeng
M
M
Dubowitz
V
V
D000818:Animals; D001921:Brain / Q000473:pathology* / Q000503:physiopathology*; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D007223:Infant; D007797:Laminin / Q000172:deficiency*; D008279:Magnetic Resonance Imaging; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D009136:Muscular Dystrophies / Q000235:genetics* / Q000473:pathology* / Q000503:physiopathology
D007797:Laminin