ELEVATED LEVELS OF ALBUMIN IN SOLEUS AND DIAPHRAGM MUSCLES OF MDX MICE

Muscle damage is often associated with an influx of extracellular flui d containing albumin into the muscle, Muscles affected by muscular dys trophy undergo severe muscle damage; therefore, the hypothesis was tes ted that muscles of dystrophic (mdx) mice contain elevated levels of a lbumin, Albumin levels in diaphragm (DIA) and soleus (SOL) muscles of control and mdx mice were measured at 3 months and 1 year of age, Albu min in mdx DIA at 1 year of age was twice that of control, In mdx SOL at 1 year of age albumin was increased 25% compared with control, The increase in albumin correlates well with the decline in function in md x DIA and SOL muscles, Electron microscopy of muscles suggests that al bumin is co-localized with transverse tubules of muscle fibers and thu s may be mainly located in extracellular fluid. We conclude that album in is elevated in muscles affected by muscular dystrophy and suggest t hat this may be of clinical importance in view of substances bound to albumin under physiological conditions.