Changes in fiber composition of soleus muscle during rat hindlimb suspension.
Changes in fiber composition of soleus muscle during rat hindlimb suspension.
复制标题
大鼠后肢悬吊过程中比目鱼肌纤维成分的变化。
DOI：
10.1152/jappl.1988.65.3.1191
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Dudenhoeffer,GA
中科院分区：
文献类型：
--
作者：
Templeton,GH;Sweeney,HL;Timson,BF;Padalino,M;Dudenhoeffer,GA
先前已证明，长期减少大鼠后肢的重力负荷以模拟骨骼肌中近零重力的影响会引起比目鱼肌萎缩。本研究使用该模型表明，比目鱼肌萎缩的特征是含有肌球蛋白慢同工酶的组中纤维数量的减少，并且根据肌原纤维肌动球蛋白腺苷三磷酸酶（ATP酶）和NADH四唑还原酶的染色强度将其分类为I型。此外，总纤维数没有改变，而含有中间同工酶和IIa型纤维的纤维增加了。这些结果可以通过现有纤维内成分的变化或慢纤维的同时损失和中纤维和快纤维的从头合成来解释。转化的证据包括悬浮大鼠的肌肉中不存在胚胎或新生儿肌球蛋白，以及悬浮 4 周后纤维数量不变。此外，尽管 I 型和 IIa 型纤维的两组纤维面积在悬浮过程中均有所下降，但每组内纤维面积的变异性并未增加。
Chronic reduction of gravitational load in the rear limbs of rats to simulate the influence of near-zero gravity in skeletal muscles has been shown previously to elicit atrophy in the soleus muscle. Use of this model by the present investigation indicates that soleus atrophy was characterized by a decline in the number of fibers in groups that contained the slow isoenzyme of myosin and which were classified as type I from intensity of staining to myofibrillar actomyosin adenosinetriphosphatase (ATPase) and to NADH tetrazolium reductase. Furthermore total fiber number was not changed, whereas fibers containing the intermediate isoenzyme and those classified as type IIa increased. There results could be explained by either a change in the composition within existing fibers or a simultaneous loss of slow fibers and de novo synthesis of intermediate and fast fibers. Evidence for transformation included an absence of embryonic or neonatal myosin in muscles from suspended rats and the constant fiber number that was unchanged by 4 wk of suspension. Furthermore although fiber areas of both groups of type I and IIa fibers declined during suspension, variability of the fiber areas within each group did not increase.