MYOSATELLITE CELLS, GROWTH, AND REGENERATION IN MURINE DYSTROPHIC MUSCLE - A QUANTITATIVE STUDY
MYOSATELLITE CELLS, GROWTH, AND REGENERATION IN MURINE DYSTROPHIC MUSCLE - A QUANTITATIVE STUDY
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DOI：
10.1002/ar.1092080203
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发表时间：
1984-01-01
影响因子：
--
通讯作者：
TAYLOR, F
中科院分区：
文献类型：
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作者：
ONTELL, M;FENG, KC;TAYLOR, F
确定了 2、4、8 和 17 周龄小鼠营养不良 (129 ReJ dy/dy) 伸指长肌的生长和再生模式。坏死和肌纤维损失、肥大和再生导致肌纤维数量减少，其直径分布比年龄匹配的正常小鼠的趾长伸肌中发现的更广泛。在营养不良症状出现时（出生后 2 周），肌卫星细胞核与总层下核群（肌核 + 肌卫星细胞）的比率与 2 周龄对照肌肉中发现的比率相似。在控制肌肉和营养不良的肌肉中，发现肌卫星细胞的频率随着年龄的增长而降低。在第 2、4、8 和 17 周时，肌卫星细胞分别占对照肌肉中总层下核群体的 11、6、5 和 3%，以及营养不良肌肉中总层下核群体的 12、8、6 和 5%。在对照肌肉或两个最年轻的营养不良组中，没有发现肌卫星细胞与特定直径的肌纤维的优先关联。在第 8 周和第 17 周时，肌卫星细胞在营养不良肌肉的小直径、再生肌纤维上较少遇到，并且它们优先与大直径、肥大的肌纤维相关。在正常和营养不良的肌肉中，肌卫星细胞的标记指数随着年龄的增长而降低。在所有年龄段，营养不良肌肉中的肌卫星细胞标记指数（在 2、4、8 和 17 周分别为 23、7、5 和 2%）高于正常肌肉（在 2 周和 4 周分别为 5%、< 1%），而在 8 周和 17 周龄正常肌肉中未发现标记的肌卫星细胞。显然，营养不良性小鼠肌肉的再生反应强度随着年龄的增长而降低，并且该因素可能是营养不良性肌肉的再生反应无法跟上肌肉快速退化的原因。
Patterns of growth and regeneration in 2-, 4-, 8-, and 17-wk-old murine dystrophic (129 ReJ dy/dy) extensor digitorum longus muscles were determined. Necrosis and myofiber loss, hypertrophy and regeneration result in a reduced population of myofibers whose diameter distribution is more extensive than that found in the extensor digitorum longus muscles of age-matched normal mice. At the onset of dystrophic symptoms (2 wk postnatal), the ratio of myosatellite cell nuclei to the total sublaminal nuclear population (myonuclei + myosatellite cells) is similar to that found in 2-wk-old control muscles. The frequency of finding myosatellite cells decreases with age in both control and dystrophic muscles. Myosatellite cells account for 11, 6, 5 and 3% of the total sublaminal nuclear population in control muscle and 12, 8, 6 and 5% of the total sublaminal nuclear population in dystrophic muscle at 2, 4, 8 and 17 wk, respectively. No preferential association of myosatellite cells with myofibers of a particular diameter is found in control muscle or in the 2 youngest dystrophic groups. At 8 and 17 wk, myosatellite cells are less frequently encountered on small-diameter, regenerating myofibers of dystrophic muscle, and they are preferentially associated with large diameter, hypertrophied myofibers. The labeling index of myosatellite cells decreases with age in both normal and dystrophic muscle. At all ages, the myosatellite cell labeling index is higher in dystrophic muscle (23, 7, 5 and 2% at 2, 4, 8 and 17 wk, respectively) than in normal muscle (5%, < 1% at 2 and 4 wk, respectively), with no labeled myosatellite cells being found in 8- and 17-wk-old normal muscles. Evidently, the magnitude of the regenerative response of dystrophic murine muscle decreases with age and that this factor may be responsible for the inability of the regenerative response of dystrophic muscle to keep pace with the rapid muscle deterioration.