Crow M T, Stockdale F E
Dev Biol. 1986 Jan;113(1):238-54. doi: 10.1016/0012-1606(86)90126-0.
Monoclonal antibodies specific to the light- and heavy-chain subunits of chicken skeletal muscle myosin have been used to identify fast and slow myosin-containing fibers in the thigh muscles of embryonic and adult chickens and to determine when in development diversification of muscle fiber types first occurs. Primary generation fibers which expressed different MLC and MHC types were evident within the dorsal and ventral premuscle masses and in the first muscles to form in the limb. These early embryonic muscle fiber types became distributed among and within the individual muscles of the thigh in a characteristic spatial pattern which served as a "blueprint" for guiding future muscle development and predicting the future fiber composition of the muscle. Despite the continuous addition of muscle fibers to the limb throughout development, the pattern remained unchanged. Neither the time of appearance, initial specialization, nor characteristic distribution of these primary fiber types within the limb was altered during the early embryonic period by chronic neuromuscular paralysis induced by D-tubocurarine. In contrast, muscles at later stages of embryonic development were markedly affected by such treatments and underwent atrophy and loss of differential staining characteristics. These results demonstrate that diversification of fibers in terms of myosin content is one of the earliest events in the formation of these muscles and suggest that the development of avian muscles be divided into two phases: an embryonic phase during which fibers of differing myosin content appear independently of innervation to become distributed in a specific topographic pattern within each muscle as it forms, followed by a fetal phase during which innervation becomes essential for maintaining this pattern and modulating the myosin content of its fibers.
针对鸡骨骼肌肌球蛋白轻链和重链亚基的单克隆抗体，已被用于识别胚胎期和成年期鸡大腿肌肉中含快肌球蛋白和慢肌球蛋白的纤维，并确定肌肉纤维类型的分化在发育过程中何时首次出现。表达不同肌球蛋白轻链（MLC）和肌球蛋白重链（MHC）类型的初代纤维，在背侧和腹侧肌前体以及肢体中最早形成的肌肉中很明显。这些早期胚胎肌肉纤维类型以一种特征性的空间模式分布在大腿的各个肌肉之间和内部，这种模式作为一个“蓝图”，用于指导未来的肌肉发育并预测肌肉未来的纤维组成。尽管在整个发育过程中肢体不断增加肌肉纤维，但这种模式保持不变。在胚胎早期，由筒箭毒碱引起的慢性神经肌肉麻痹，并未改变这些初级纤维类型在肢体中的出现时间、初始特化或特征分布。相比之下，胚胎发育后期的肌肉受到这种处理的显著影响，出现萎缩并丧失差异染色特征。这些结果表明，就肌球蛋白含量而言，纤维的分化是这些肌肉形成过程中最早发生的事件之一，并表明禽类肌肉的发育可分为两个阶段：胚胎期，在此期间，不同肌球蛋白含量的纤维独立于神经支配出现，并在每块肌肉形成时以特定的拓扑模式分布；随后是胎儿期，在此期间，神经支配对于维持这种模式和调节其纤维的肌球蛋白含量至关重要。
