Analysis of structural proteins from biopsied human myocardium with special emphasis on methodology.

An analytical procedure for the quantitative determination of the structural proteins from a biopsied human cardiac muscle weighing approximately 1 mg was described to be applicable in clinical studies in 20 patients with various heart diseases. The principle of the method is glycerinization of heart muscle and analysis by SDS gel electrophoresis. In 6 control heart muscles obtained from patients having almost normal hearts, the pattern of the structural proteins was similar to that of the normal canine heart. Myosin heavy chain-actin ratio ranged 1.26 +/- 0.44. In 5 cases with secondary cardiac hypertrophy, the pattern of the structural proteins was the same as that of the control heart. In 4 cases with hypertrophic cardiomyopathy, an increase in myosin heavy chain was observed in 2 cases, while myosin heavy chain and alpha-actinin decreased in another 2 cases. Hypertrophy and severe disarray of myofibrils were noted in the former, and atrophy and degradation were done in the latter in electron microscopy. In 5 cases with dilated cardiomyopathies, the relative contents of myosin heavy chain and alpha-actinin was reduced in all cases together with atrophy and degradation of myofibrils.