The long term objective of this program is to determine by comparative enzymological studies the genetic lesion of muscular dystrophy in the chicken. Studies in progress include an examination of mechanism of clearance of muscle adenylate kinase and AMP aminohydrolase from the blood stream of the chicken. These enzymes are cleared rapidly, primarily by the liver and spleen, accounting for their low or negligible activity in serum of dystrophic chickens in contrast to pyruvate kinase and creatine kinase. Are specific receptors involved? Do lysosomes participate in this process? Lysosomes from normal and dystrophic muscle are also being compared. The plan is to develop a procedure to obtain pure muscle lysosomal membranes and characterize them in an attempt to ascertain the differences in the structure latency of lysosomes from normal and dystrophic muscle. Finally, the structure of a presumed oligosaccharide of AMP aminohydrolase from normal and dystrophic muscle is being investigated.