THE COMPARATIVE HISTOCHEMISTRY OF MUSCLE PLASMALOGENS

The distribution of plasmalogens in muscle tissues was studied histochemically by the plasmal reaction. Plasmalogens were found in the sarcoplasm, sarcosomes (perinuclear and interfibrillar), and in the intercalated disks of heart muscle in some mammals. These observations were supplemented by paper chromatographic analysis of the lipids extracted from muscle tissues, and from muscle cell fractions. All muscles contained both choline plasmalogen and ethanolamine plasmalogen, but cardiac muscle had a higher content of choline plasmalogen than skeletal muscle, which in turn contained more ethanolamine plasmalogen. No free fatty aldehydes were found in muscle tissues. The specificity of the plasmal reaction is discussed and the advantages of using a combined histochemical and chromatographic approach to the study of tissue lipids are illustrated.