Effects of anabolic steroids on the muscle cells of strength-trained athletes.

PURPOSE: Athletes who use anabolic steroids get larger and stronger muscles. How this is reflected at the level of the muscle fibers has not yet been established and was the topic of this investigation. METHODS: Muscle biopsies were obtained from the trapezius muscles of high-level power lifters who have reported the use of anabolic steroids in high doses for several years and from high-level power lifters who have never used these drugs. Enzyme-immunohistochemical investigation was performed to assess muscle fiber types, fiber area, myonuclear number, frequency of satellite cells, and fibers expressing developmental protein isoforms. RESULTS: The overall muscle fiber composition was the same in both groups. The mean area for each fiber type in the reported steroid users was larger than that in the nonsteroid users (P < 0.05). The number of myonuclei and the proportion of central nuclei were also significantly higher in the reported steroid users (P < 0.05). Likewise, the frequency of fibers expressing developmental protein isoforms was significantly higher in the reported steroid users group (P < 0.05). CONCLUSION: Intake of anabolic steroids and strength-training induce an increase in muscle size by both hypertrophy and the formation of new muscle fibers. We propose that activation of satellite cells is a key process and is enhanced by the steroid use. The incorporation of the satellite cells into preexisting fibers to maintain a constant nuclear to cytoplasmic ratio seems to be a fundamental mechanism for muscle fiber growth. Although all the subjects in this study have the same level of performance, the possibility of genetic differences between the two groups cannot be completely excluded.

Cellular adaptation of the trapezius muscle in strength-trained athletes.

The aim of this study was to elucidate the cellular events that occur in the trapezius muscle following several years of strength training. In muscle biopsies from ten elite power lifters (PL) and six control subjects (C), several parameters were studied: cross-sectional area of muscle fibres, myosin heavy chain composition (MHC) and capillary supply [capillaries around fibres (CAF) and CAF/fibre area]. A method was also developed for counting the number of myonuclei and satellite cell nuclei. The proportion of fibres expressing MHC IIA, the cross-sectional area of each fibre type and the number of myonuclei, satellite cells and fibres expressing markers for early myogenesis were significantly higher in PL than in C (P<0.05). A significant correlation between the myonuclear number and the cross-sectional area was observed. Since myonuclei in mature muscle fibres are not able to divide, we suggest that the incorporation of satellite cell nuclei into muscle fibres resulted in the maintenance of a constant nuclear to cytoplasmic ratio. The presence of small diameter fibres expressing markers for early myogenesis indicates the formation of new muscle fibres.

Reduction mammaplasty: symptoms, complications, and late results. A retrospective study on 242 patients.

During a three year period, 242 women ranging from 16-68 years with hypertrophic breasts underwent reduction mammaplasty by Skoog's, Strömbeck's, Regnault's, or the nipple-areola transplantation technique. After a follow-up period of three years the results were evaluated by requesting the patients to complete a questionnaire and also by abstracting information from the records. The most common preoperative symptoms were pain in the head, neck, and shoulder-region, sufficient to cause a working disability in approximately half of the patients. Psychological distress regarding appearance was more common among the younger women. The mean weight of the removed tissue was 1184 g (SD 583), which correlated positively with both increasing age and body mass index (BMI). The overall complication rate was 10%, which also correlated positively with BMI. The postoperative evaluation indicated that 86%-96% of patients experienced relief of symptoms postoperatively and 92% of the total number of patients were satisfied with the operation. Approximately three quarters of the women who had a working disability prior to the operation were able to return to their former occupations postoperatively.

Structural changes in male trapezius muscle with work-related myalgia.

Muscular changes in male forest machine operators with work-related neck and shoulder myalgia were studied. Enzyme cyto- and immunohistochemical analysis was carried on muscle biopsies obtained from ten myalgic subjects (M), nine non-myalgic selected in the same work place (NM) and six healthy young men (C). The M group displayed a significant increase in type IIA fibres in comparison to the C group. This hypertrophy was accompanied by a parallel increase in the capillary bed. Both the M and NM groups exhibited an increase in fibres with a disorganised mitochondrial pattern. Interestingly, fibres lacking cytochrome c oxidase occurred in the M group (0.9%) but also in the NM group (0.5%), suggesting a mitochondrial defect. Central nuclei (5.2%) and developmental myosin (3%) were also more frequent in the M group. These changes are probably related to injury-regeneration cycles. These data support the association between the work conditions and muscle changes in work-related trapezius myalgia.