Studies on Experimental Myopathy Followed by Immunization with the Membranes of Sarcoplasmic Reticulum or T-System

Abstract

The membranes of sarcoplasmic reticulum (SR) and transverse tubule system (T-system) were isolated from rat muscle homogenate using the centrifugation with sucrose linear density gradient. Mice given these membrane fractions subcutaneously with or without FCA developed moderate myositic changes such as muscle fiber degenuration, muscle fiber atrophy, central nuclei, chain nuclei and phagocyte infiltrations. Histochemical analysis of succinic dehydrogenase demonstrated remarkable atrophy of type I fibers than type II fibers. These changes were more prominent in mice immunized with these fractions with FCA than without FCA. Humoral antibodies against these fractions were observed by the immunofluorescence method and micro-Ouchterlony gel diffusion method. Myopathic low amplitude voltages appeared on the electromyogram of these immunized mice. The waning phenomenon was induced in mice immunized with SR fraction by supramaximal repetitive stimulations. The thymus was hyperplastic with enlarged lymphnodes, although thymitis was not clear histologically.