d'Albis A, Lenfant-Guyot M, Janmot C, Chanoine C, Weinman J, Gallien C L
Dev Biol. 1987 Sep;123(1):25-32. doi: 10.1016/0012-1606(87)90423-4.
Changes both in the ATPase myofibrillar profile and in the electrophoretic pattern of myosin isoforms were examined in the mouse dorsal skeletal muscle (longissimus) during postnatal development. In the newborn, only type II C and a few type I fibers were present; differentiation into type II A and II B fibers took place during the 3 weeks following birth. During the same period, a transition from three neonatal isomyosins to four adult isoforms was observed. The two phenomena were related to a marked increase in the serum thyroid hormones levels. Hypothyroidism and hyperthyroidism experiments were performed. Hypothyroidism produced by propylthiouracil treatment of pregnant females and thiourea injections of the litters was shown to induce a complete inhibition of postnatal muscular differentiation. Hyperthyroidism produced by triiodothyronine treatment of the neonate mice significantly accelerated the myosin transition and the switch in the myofibrillar pattern. Our results suggest a primordial role for thyroid hormones in directly regulating the appearance of myosin and fiber adult types and in modulating directly or indirectly the disappearance of the neonatal types.
在出生后发育过程中，对小鼠背部骨骼肌（最长肌）的肌球蛋白ATP酶肌原纤维分布变化和肌球蛋白同工型的电泳图谱变化进行了研究。新生小鼠中仅存在II C型和少量I型纤维；出生后的3周内发生了向II A型和II B型纤维的分化。在同一时期，观察到从三种新生儿肌球蛋白同功型向四种成人同工型的转变。这两种现象与血清甲状腺激素水平的显著升高有关。进行了甲状腺功能减退和甲状腺功能亢进实验。对怀孕雌性小鼠用丙硫氧嘧啶治疗并对幼崽注射硫脲所产生的甲状腺功能减退被证明可诱导出生后肌肉分化的完全抑制。对新生小鼠用三碘甲状腺原氨酸治疗所产生的甲状腺功能亢进显著加速了肌球蛋白转变和肌原纤维模式的转换。我们的结果表明，甲状腺激素在直接调节肌球蛋白和成年纤维类型的出现以及直接或间接调节新生儿类型的消失方面起着重要作用。
