Electrophoresis of the non-structural proteins from normal and atrophic muscles of the rabbit and of man

Abstract

The proteins of normal and atrophied skeletal muscles of the rabbit and of man, soluble in salt solutions of low ionic strength and pH about 7, were studied by means of electrophoresis. Atrophy of rabbit leg muscles was caused by severance of the motoric nerve, by immobilisation of a leg in a plaster cast, by inanition and by vitamin-E deficiency. No matter which of these methods was used to induce muscular atrophy, the electrophoresis diagrams obtained always showed the same alterations as compared with the diagrams obtained for normal muscles. The most remarkable feature was the increase of the percentages of more rapidly moving components and the decrease of the percentages of the slower components. While the total amount of protein, extractable by a salt solution of ionic strength 0.13 and pH 7.15 from the whole muscle, had considerably decreased, the amount of the most rapidly migrating component (II), distinguishable in the diagrams, had remained constant.

Normal human muscles differed little from normal rabbit muscles. The flat intermediate part of the diagrams, which had been maintained in the case of the atrophied rabbit muscles, had, however, completely disappeared in the case of chronic human muscular atrophy caused by immobilization, existing during several decades. The time of existence of the atrophy may be the cause of this difference, as the atrophy of the rabbit muscles had developed in the course of a few weeks.