Number of contractions to maintain mass and force of a denervated rat muscle
Number of contractions to maintain mass and force of a denervated rat muscle
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DOI：
10.1002/mus.20054
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发表时间：
2004-07-01
期刊：
影响因子：
3.4
通讯作者：
Dennis, RG
中科院分区：
文献类型：
--
作者：
Dow, DE;Cederna, PS;Dennis, RG
失神经支配的大鼠指长伸肌在5周内失去66%的质量、91%的力量和76%的纤维横截面积。我们之前确定了电刺激失神经大鼠EDL肌肉的参数，以产生足以维持质量和力接近控制值的强直性收缩。利用这些参数，我们检验了每天收缩次数存在一个范围的假设，在这个范围内，质量、最大力量和纤维CSA的值都低于神经控制肌肉的值。在5周的时间里，去神经的EDL肌肉每天被刺激产生25到5000次收缩，收缩被恒定的休息间隔隔开，每天重复24小时。每天收缩少于200次或超过800次时，力量不能保持，而每天收缩少于50次时，质量和纤维CSA也不能保持。在长时间的失神经状态下保持肌肉质量和力量的刺激方案可以最大限度地减少临床上与失神经萎缩相关的问题。
Within 5 weeks, denervated extensor digitorum longus (EDL) muscles of rats lose 66% of mass, 91% of force, and 76% of fiber cross-sectional area (CSA). We previously determined the parameters of electrical stimulation for denervated rat EDL muscles to generate tetanic contractions sufficient to maintain mass and force close to control values. Using these parameters, we tested the hypothesis that a range exists for number of contractions per day, below and above which values for mass, maximum force, and fiber CSA are lower than values for innervated control muscles. For 5 weeks, denervated EDL muscles were stimulated to generate between 25 and 5000 contractions daily with contractions separated by constant intervals of rest, repeated 24 h per day. Force was not maintained with fewer than 200 or more than 800 contractions daily, whereas mass and fiber CSA were not maintained with fewer than 50 contractions daily. Protocols of stimulation that maintain muscle mass and force during prolonged periods of denervation may minimize problems clinically associated with denervation atrophy.