EFFECTS OF DENERVATION ON PROTEIN TURNOVER OF RAT SKELETAL-MUSCLE
EFFECTS OF DENERVATION ON PROTEIN TURNOVER OF RAT SKELETAL-MUSCLE
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DOI：
10.1042/bj1560071
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发表时间：
1976-01-01
影响因子：
4.1
通讯作者：
GOLDSPINK, DF
中科院分区：
文献类型：
--
作者：
GOLDSPINK, DF
在比目鱼肌和趾长伸肌中研究了去神经对肌重、蛋白质合成和分解速率以及RNA浓度的影响。尽管比目鱼肌在坐骨神经切断后发生了真正的萎缩，但趾长伸肌仍继续生长，尽管生长速度低于受神经支配的对照组。在24小时后，神经节蛋白质分解增加，在两种肌肉类型相比，内部控制，并保持这样的整个10天的研究。这种增加的catabolism可能产生的构象变化的蛋白质失神经支配后的可能性没有得到证实，作为肌原纤维或可溶性蛋白的失神经支配和控制组织同样容易降解在体外由三种蛋白酶。酪氨酸摄取到失神经的趾长伸肌在整个10天的研究减少，而两个阶段的增加运输的氨基酸被发现在比目鱼肌。去神经支配后1天和2天，蛋白质合成率显着下降，结果表明，这些变化可能是由于核糖体参与翻译过程中的减少。这些最初的下降并没有保持，蛋白质合成的速度实际上是增加时，与对照组相比，在第7和10天。7天失神经组织的合成率增加反映为肌原纤维和可溶性蛋白的成比例增加。有人建议，在这个时候，合成的增加可能是由于增加的abailability和积极参与的核糖体，这些合成代谢的趋势可能是由自发性纤维颤动和/或被动拉伸失神经肌肉的量。
The effects of denervation on muscle weight, rates of protein synthesis and breakdown, and RNA concentraitons were studied in the soleus and extensor digitorum longus muscle. Althrough the soleus underwent a true atrophy after section of the sciatic nerve, the extensor digitorum longus continued to grow, albeit at a lower rate than innervated controls. At 24h after nerve section protein breakdown was increased in both muscle types when compared with internal controls, and remained so throughout the 10 days studied. The possibility that this increased catabolism might arise from conformational changes of proteins after denervation was not substantiated, as myofibrillar or soluble proteins of denervated and control tissues were equally susceptible to degradation in vitro by three proteinases. Tyrosine uptake into the denervated extensor digitorum longus was decreased throughout the 10 days studied, whereas two phases of increased transport of the amino acid were found in the soleus. Significant decreases in rates of protein synthesis were found 1 and 2 days after denervation and results are presented that suggest that these changes may result from a decrease in ribosomal involvement in the translation process. These initial decreases were not maintained and the rate of protein synthesis was in fact increased when compared with controls, at 7 and 10 days. The increased synthetic rates of the 7-day denervated tissues were reflected as proportional increases in both myofibrillar and soluble proteins. It is suggested that the increase in synthesis at this time may result from an increase in both the abailability and active involvement of ribosomes, and that these anabolic trends may be caused by spontaneous fibrillation and/or the amount of passive stretching of the denervated muscles.