Investigation of the organelle pathology of skeletal muscle in chronic alcoholism.

The muscle abnormalities associated with chronic alcohol consumption were studied by applying histological and biochemical techniques to tissue obtained by percutaneous needle biopsy from the quadriceps muscles of 41 patients. Measurement of the fibre size showed atrophy of both type I (p less than 0.05) and type II (p less than 0.001) fibres. The degree of atrophy was more severe for type II fibres (33% reduction in median diameter) than type I (17%). Marker enzyme activities for the principal organelles were assayed. Compared with biopsy specimens from non-alcoholic controls, no differences were found in the activities of lysosomal, mitochondrial, peroxisomal, cytosolic, sarcolemmal, or sarcoplasmic reticulum enzymes, expressed per microgram DNA. A reduction in the protein to DNA ratio was evident in severely atrophic biopsies, and this was associated with a significant reduction of myofibrillary Ca2+-ATPase activity. These results suggest a selective loss of type II fibre myofibrillary protein and do not confirm earlier suggestions of specific mitochondrial damage.