Denervation does not change the ratio of collagen I and collagen III mRNA in the extracellular matrix of muscle
Denervation does not change the ratio of collagen I and collagen III mRNA in the extracellular matrix of muscle
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DOI：
10.1152/ajpregu.00483.2006
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发表时间：
2007-02-01
影响因子：
2.8
通讯作者：
Baar, Keith
中科院分区：
文献类型：
--
作者：
Arruda, Ellen M.;Mundy, Kevin;Baar, Keith
失神经支配不改变肌肉细胞外基质中I型胶原和III型胶原mRNA的比例。Am J Physiol Regul Integr Comp Physiol 292：R983-R987，2007年。首次发表于2006年9月28日; doi：10.1152/ajpregu.00483.2006。已知去神经支配或不活动会减少肌肉的质量并改变肌肉的表型和肌腱的力学。已经提出，肌肉的细胞外基质（ECM）的胶原蛋白的转变，增加III型胶原蛋白和减少I型胶原蛋白，可能是观察到的变化的部分原因。我们直接研究了这一假设，使用定量实时PCR的肌肉和肌腱，已被去神经5周。5周的去神经导致胶原蛋白浓度增加2.91倍，但肌肉中胶原蛋白的含量没有变化，而肌腱中胶原蛋白的浓度或含量都没有变化。去神经5周后，肌肉ECM中I型胶原、III型胶原和赖氨酰氧化酶mRNA的表达下降（分别为76 +/-1.6%、73 +/-2.3%和83 +/-3.2%）。天狼星红染色证实了早期观察到的染色颜色从红色变为绿色。考虑到所观察到的胶原蛋白I和III mRNA的等效减少，这表明肌肉ECM的取向发生变化，变得与肌纤维的轴更加对齐，而胶原蛋白类型没有变化。胶原蛋白取向的变化可能有助于通过增加ECM的刚度来保护较小的肌纤维免受损伤，并且可以部分解释为什么最接近肌肉的肌腱区域在不活动后变得更硬。
Denervation does not change the ratio of collagen I and collagen III mRNA in the extracellular matrix of muscle. Am J Physiol Regul Integr Comp Physiol 292: R983-R987, 2007. First published September 28, 2006; doi: 10.1152/ajpregu.00483.2006.-Denervation or inactivity is known to decrease the mass and alter the phenotype of muscle and the mechanics of tendon. It has been proposed that a shift in the collagen of the extracellular matrix (ECM) of the muscle, increasing type III and decreasing type I collagen, may be partially responsible for the observed changes. We directly investigated this hypothesis using quantitative real-time PCR on muscles and tendons that had been denervated for 5 wk. Five weeks of denervation resulted in a 2.91-fold increase in collagen concentration but no change in the content of collagen in the muscle, whereas in the tendon there was no change in either the concentration or content of collagen. The expression of collagen I, collagen III, and lysyl oxidase mRNA in the ECM of muscle decreased (76 +/- 1.6%, 73 +/- 2.3%, and 83 +/- 3.2%, respectively) after 5 wk of denervation. Staining with picrosirius red confirmed the earlier observation of a change in staining color from red to green. Taken with the observed equivalent decreases in collagen I and III mRNA, this suggests that there was a change in orientation of the ECM of muscle becoming more aligned with the axis of the muscle fibers and no change in collagen type. The change in collagen orientation may serve to protect the smaller muscle fibers from damage by increasing the stiffness of the ECM and may partly explain why the region of the tendon closest to the muscle becomes stiffer after inactivity.