Endurance exercise modulates neuromuscular junction of C57BL/6NNia aging mice
Endurance exercise modulates neuromuscular junction of C57BL/6NNia aging mice
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DOI：
10.1152/jappl.1997.83.1.59
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发表时间：
1997-07-01
影响因子：
3.3
通讯作者：
Fahim, MA
中科院分区：
文献类型：
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作者：
Fahim, MA
以C57 BL/6 NNia小鼠为研究对象，研究了年龄和耐力运动对臀大肌神经肌肉接头（NMJ）生理和形态的影响。小鼠在啮齿动物跑步机上运动，从7或25月龄开始，以28 m/min持续60 min/天，5天/周持续12周。记录10月龄和28月龄对照组和运动组小鼠NMJ细胞内自发性微小终板电位（MEPP）和终板电位量子含量（EPP）。耐力运动导致MEPP振幅（23%），量子含量和安全范围显着增加，并在MEPP频率的年轻小鼠的显着下降，在静息膜电位或膜电容没有变化。三个月的耐力运动导致老年小鼠的MEPP频率增加（41%），MEPP振幅减少（15%），量子含量和安全范围。耐力运动导致年轻动物的神经末梢明显更大（24%），表明功能适应。运动28月龄小鼠的神经末梢小于相应的对照组小鼠，这表明运动最大限度地减少了与年龄相关的神经末梢的发育。结论：青年和老年臀大肌对耐力运动的不同生理反应与其形态学反应是平行的。这表明，小鼠NMJ在衰老过程中经历了生理和形态重塑的过程，这种可塑性可以通过耐力运动进行不同的调节。
The effect of age and endurance exercise on the physiology and morphology of neuromuscular junctions (NMJ) of gluteus maximus muscle was studied in C57BL/6NNia mice. Mice were exercised, starting at 7 or 25 mo of age, at 28 m/min for 60 min/day, 5 days/wk for 12 wk, on a rodent treadmill. Intracellular recordings of spontaneous miniature endplate potentials (MEPP) and the quantal content of endplate potentials (EPP) were recorded from NMJ of 10- and 28-mo-old control and exercised mice. Endurance exercise resulted in significant increases in MEPP amplitudes (23%), quantal content, and safety margin, and a significant decrease in MEPP frequency of young mice, with no change in resting membrane potential or membrane capacitance. Three months of endurance exercise resulted in an increase in MEPP frequency (41%) and decreases in MEPP amplitudes (15%), quantal content, and safety margin of old mice. Endurance exercise resulted in significantly larger nerve terminals (24%) in young animals, suggesting functional adaptation. Nerve terminals in exercised 28-mo-old mice were smaller than in the corresponding control mice, an indication that exercise minimized age-related nerve terminal elaboration. It is concluded that the different physiological responses of young and old gluteus maximus muscles to endurance exercise parallel their morphological responses. This suggests that the mouse NMJ undergoes a process of physiological and morphological remodeling during aging, and such plasticity could be modulated differently by endurance exercise.