Fiber-type-specific αB-crystallin distribution and its shifts with T3 and PTU treatments in rat hindlimb muscles
Fiber-type-specific αB-crystallin distribution and its shifts with T3 and PTU treatments in rat hindlimb muscles
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DOI：
10.1152/jappl.2000.88.4.1355
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发表时间：
2000-04-01
影响因子：
3.3
通讯作者：
Hatta, H
中科院分区：
文献类型：
--
作者：
Atomi, Y;Toro, K;Hatta, H
采用3,5,3′-三碘甲状腺原氨酸（T-3）和丙硫脲嘧啶（PTU）治疗8周后，观察成年大鼠比目鱼肌和指长伸肌(EDL) α - b -晶体蛋白含量的变化。从反应性灰度到特异性抗α b -晶体蛋白抗体，研究了与纤维类型相关的α b -晶体蛋白表达的细胞分布以及随这些处理的分布变化。经T-3处理后，比目鱼肌和EDL肌α b -晶体蛋白含量均显著降低，而经PTU处理后，EDL肌α b -晶体蛋白含量显著升高2倍以上。在对照比目鱼肌和EDL肌中，ⅰ型纤维的灰度值高于ⅱ型纤维。α b -晶体蛋白在ⅱ型亚型中的表达是肌肉特异性的；对照EDL肌为I型>型IIa型>型IIx >型IIb型，比目鱼肌为大于或等于IIa型。经Ts治疗后，这一关系在两种肌肉中基本没有变化，尤其是在EDL肌肉中保持得很好。在PTU伴甲状腺功能减退的情况下，IIa型和IIx型纤维的平均α b -晶体蛋白水平显著低于对照组。因此，纤维类型与应激蛋白α - b -晶体蛋白表达方式之间的关系是肌肉特有的，并且在甲状腺激素的作用下受到很好的调节，特别是在快速EDL肌肉中。
Changes in alpha B-crystallin content in adult rat soleus and extensor digitorum longus (EDL) were examined after 8 wk of 3,5,3'-triiodothyronine (T-3) and propylthiouracil (PTU) treatments. Cellular distributions of alpha B-crystallin expression related to fiber type, and distribution shifts with these treatments were also examined in detail from the gray level of reactivity to specific anti-alpha B-crystallin antibody. alpha B-crystallin content in both soleus and EDL muscles was significantly decreased after T-3, and that in EDL was significantly increased over twofold after PTU treatment. In both control soleus and EDL muscles, the gray level of type I fibers was higher than that of type II fibers. alpha B-crystallin expression among type II subtypes was muscle specific; the order was type I > IIa > IIx > IIb in control EDL muscle and type IIx greater than or equal to IIa in soleus muscle. The relation was basically unchanged in both muscles after Ts treatment and was, in particular, well maintained in EDL muscle. Under hypothyroidism conditions with PTU, the mean alpha B-crystallin levels of type IIa and IIx fibers were significantly lower than levels under control conditions. Thus the relation between fiber type and the expression manner of stress protein alpha B-crystallin is muscle specific and also is well regulated under thyroid hormone, especially in fast EDL muscle.