REGENERATION-BLOCKED MDX MUSCLE - IN-VIVO MODEL FOR TESTING TREATMENTS

We have refined the mdx mouse as a clinical model for Duchenne dystrop hy. Our power estimates, primary measures, regular sacrifice intervals , and quality checks constitute a high-speed, low-cost system for prec linically testing therapies designed to slow muscle destruction in Duc henne dystrophy. Irradiated (18 Gy) and contralateral shielded anterio r tibial muscles were studied in 21-day-old mdx and normal mice at the time of irradiation and 4, 8, 12, 16, and 20 weeks thereafter. Regene ration-blocked mdx (irradiated) muscle expressed muscular dystrophy as progressive wasting after a brief (4 week) period of growth. Regenera tion-blocked normal muscle showed stunted growth but neither progressi ve wasting nor microscopic pathological changes. (C) 1997 John Wiley & Sons, Inc.