PROBLEMS OF A MUSCLE DISEASE 



specimens of muscle weighing not more than one hundred milH- 

 grams. 



The problem of adequate bases of reference for constituents of 

 diseased tissue in general is one of the principal barriers to the develop- 

 ment of a rational discipline of chemical pathology. It is becoming 

 increasingly evident that practical methods for determination of the 

 residual mass of parenchymal cells of affected organs will have to be 

 devised before full consideration can be given to possible alterations in 

 concentration of enzymes, substrates, metabolites, and metallic cata- 

 lysts occurring in tissue as a result of affection by disease. Since, in 

 the chemical analysis of diseased organs, we are going to be faced 

 constantly with the need of knowing the net quantities of various 

 tissue constituents, it is safe to assume that increasing attention will 

 be paid in the future to the problem of the relation of the concentration 

 of tissue constituents to differential cellular mass. 



Some of the difficulties inherent in the selection of a proper base 

 of reference for constituents of diseased tissue can be avoided by ascer- 

 taining the ratio between the concentrations of two substances in a 

 given specimen of material and comparing it with the ratio which is 

 found for these constituents in similar tissues of normal organs. Not- 

 able among these is the familiar respiratory quotient, which, since it 

 measures the ratio of the production of carbon dioxide to oxygen con- 

 sumption, can be considered independently, within certain limits, of 

 the variable extraneous constituents of the specimen. Studies of the 

 respiratory quotient by means of the method of Dickens and Simers (4) 

 of specimens of muscle removed from patients exhibiting various stages 

 of progressive muscular dystrophy did not reveal values differing sig- 

 nificantly from those obtained for specimens of normal muscle removed 

 during surgical operation (17). The carbon dioxide and oxygen 

 quotients were extremely low in the diseased tissue, but the ratio of 

 carbon dioxide production to oxygen consumption was normal. It 

 should be pointed out that, with respect to the oxygen consumption, 

 specimens of surviving muscle from patients with progressive muscular 

 dystrophy differ markedly from specimens of muscle taken from animals 

 which have been deprived of vitamin E. Houchin and Matill have 

 shown that muscle tissue removed from animals on diets deficient in 

 vitamin E was characterized by marked increase in oxygen consump- 

 tion (10), and, moreover, that the oxygen uptake of the muscle speci- 



