Pharmocologic therapy of dystrophy in man and animals

Dystrophic symptoms prevented by phenobarbital in avian muscular dystrophy

New Hampshire normal (line 412) and dystrophic (line 413) chickens were treated with central stimulants and central depressants, respectively, once a day from the 2nd to the 10th day after hatching, and effects of the treatment were examined on a number of muscle fibers, areas of muscle fibers, and the coefficient of variation of a muscle on the 13th day. Central depressants, especially phenobarbital, effectively prevented development of the dystrophic symptoms, whereas central stimulants made normal chickens "dystrophic". The righting ability of the dystrophic chickens was normal after treatment with 10 mg/kg of phenobarbital during the early postnatal period from the 2nd to the 28th day after hatching.

Drugs in muscular dystrophy of the chicken: corticosterone-21-acetate

In a previous series of 22-day evaluations of 31 compounds, only corticosterone-21-acetate (C-21-A) increased righting ability of genetically dystrophic chickens to a greater extent than the standard of comparison, methysergide maleate. In the present study, C-21-A was subjected to longer-term trials of up to 48 days, and additional signs of the myopathy were examined. The highest doses of C-21-A increased righting ability for the duration of the trials, decreased the typically elevated plasma levels of creatine kinase (CK) activity by more than 80%, and improved morphology of the dystrophic pectoralis major muscle at the light microscopic level. The major adverse effect of C-21-A, reduction of body weight, was consistently observed at the relatively high doses needed to increase righting ability. That alone, however, could not account for increased righting ability, and plasma CK activity was decreased even at doses that did not reduce body weight. The results show that C-21-A is the most effective compound yet tested in this system and, perhaps more significantly, provides the first evidence that it is possible to identify compounds that improve muscle morphology in a hereditary myopathy using a short-term, step-wise system.