CORTICOSTEROID-THERAPY DOES NOT ALTER THE THRESHOLD FOR CONTRACTION-INDUCED INJURY IN DYSTROPHIC (MDX) MOUSE DIAPHRAGM

The effects of methylprednisolone therapy on the susceptibility of dys trophin-deficient myofibers to contraction-induced injury were evaluat ed in the mdx mouse diaphragm model of Duchenne dystrophy. Mdx myofibe rs were abnormally vulnerable to injury induced by high-stress eccentr ic contractions. However, methylprednisolone therapy did not significa ntly alter the degree of contraction-induced injury. These data sugges t that beneficial effects of corticosteroid therapy in Duchenne dystro phy are unlikely to be related to a change in the threshold for contra ction-induced myofiber damage. (C) 1998 John Wiley & Sons, Inc.