Microcirculation: loss of an enzyme activity in chickens with hereditary muscular dystrophy.

Histochemical localization of an alkalinie phosphatase, with (alpha)-naphthyl phosphate used as substrate, shows that activity in breast muscle from normal chickens is restricted to the microvasculature. In chickens with hereditary muscular dystrophy, this enzyme activity disappears from capillaries and small arterioles before degeneraction of muscle fibers is detectable. This loss is retarded in myopathic chickens that have received oxygen therapy.