Metabolism Studies in Nutritional Muscular Dystrophy: Six Figures

Abstract

The metabolism experiments have shown that pronounced changes take place in the metabolism of the dystrophic organism. For the sake of clarity, the results will be summarized by citing the changes which take place during definite stages in the course of the disease. During the period of approaching dystrophy: The weight curve wavers or drops slowly, while the consumption of food and water becomes less. The urine excretion also decreases and it becomes acid in reaction. The urinary chlorides decrease gradually while the phosphorus elimination increases. The total nitrogen excretion decreases somewhat, but the creatinine excretion remains practically constant while that of creatine increases by leaps and bounds. At the ‘critical point’: The body weight declines sharply. The ratio of urine output to the water intake approaches the value of 1:1 as the acidotic metabolism develops. There is marked diuresis accompanied by a relatively slight increase in creatinine, total nitrogen, phosphorus and chloride excretion and an enormous increase in the creatine elimination. At this point the creatine N, calculated as per cent of total N, doubles or trebles itself and the nitrogen balance becomes definitely negative. During the period of progressive dystrophy, i.e., from the ‘critical point’ to the time of death: The weight continues to fall rapidly. The phosphorus and chloride excretion gradually decrease. The creatinine and total nitrogen decrease from the high level reached at the ‘critical point,’ while the creatine excretion continues to rise till the time of death. The urine volume decreases following the brief strong diuresis at the critical point, but just before death a marked diuresis occurs again. During the period of recovery, following a change of diet at the ‘critical point’: The weight increases at first slowly, then very rapidly. The food and water intake increases gradually. The ratio of the urine output to water intake soon returns to the normal value of 1:2. The urine almost immediately becomes alkaline. The excretion of phosphorus and chloride approaches the values normal for that diet. The nitrogen balance becomes positive and the creatine elimination approaches the normal level. Meanwhile, the rabbit gradually loses the symptoms of dystrophy and behaves perfectly normal.