Evolution of pathological changes in the gastrocnemius of the mdx mice correlate with utrophin and beta-dystroglycan expression.

Utrophin can function in muscle as a substitute for dystrophin and its over-expression has been used successfully to ameliorate mdx muscle pathology. Despite of this fact, there are no detailed studies on the expression of endogenous skeletal muscle utrophin- and dystrophin-associated glycoproteins throughout the life span of mdx mice. We have monitored, sequentially, the expression of matrix metalloproteinase-9 (MMP-9), myosin heavy chain, utrophin and beta-dystroglycan, as well as the mRNA expression of utrophin and of structurally related proteins, in mdx and control mice.

Longitudinal pathologic study of the gastrocnemius muscle group in mdx mice.

Muscle necrosis in mdx mice is rare before the 2nd week of life, but becomes pronounced from weeks 2 to 6. There is no agreement on what happens after this age. Using sequential microscopic histology, immunohistochemistry and histomorphometry, we studied the evolution of muscle pathology throughout the mdx life span.

Distribution and effects of a single intramuscular injection of India ink in mice.

Our goal has been to study the distribution and effects following a single intramuscular injection of a substance using India ink as a tracer. We injected 30 microl India ink in the gastrocnemius muscle group of C57Bl10 mice. Hematoxylin-Eosin, Trichrome stains and polyclonal anti-laminin, anti-collagen-IV and anti-dystrophin were used.