Hoh J F, Hughes S, Hale P T, Fitzsimons R B
Department of Physiology, University of Sydney, NSW, Australia.
J Muscle Res Cell Motil. 1988 Feb;9(1):30-47. doi: 10.1007/BF01682146.
Changes in myosin synthesis during the postnatal development of the fast extensor digitorum longus (EDL) and the slow soleus muscles of the kitten were examined using immunocytochemical techniques supplemented by pyrophosphate gel electrophoresis and gel electrophoresis-derived enzyme linked immunosorbent assay (GEDELISA) of myosin isoforms. The antibodies used were monoclonals against heavy chains of slow and fast myosins and a polyclonal against foetal/embryonic myosin. In both muscles in the newborn kitten, there was a population of more mature fibres which stained strongly for slow but weakly for foetal/embryonic myosin. These fibres were considered to be primary fibres. They formed 4.8% of EDL fibres and 26% of soleus fibres at birth, and continued to express slow myosin in adult muscles. The less mature secondary fibres stained strongly for foetal/embryonic myosin, and these could be divided into two subpopulations; fast secondaries in which foetal/embryonic myosin was replaced by fast myosin, and slow secondaries in which the myosin was replaced by slow myosin. At 50 days the EDL had a large population of fast secondaries (83% of total fibres) and a small population of slow secondaries which gradually transformed into fast fibres with maturity. The vast majority of secondary fibres in the soleus were slow secondaries, in which slow myosin synthesis persisted in adult life. There was a restricted zone of fast secondaries in the soleus, and these gradually transformed into slow fibres in adult life. It is proposed that the emergence of primary fibres and the two populations of secondary fibres is myogenically determined.
利用免疫细胞化学技术，并辅以焦磷酸凝胶电泳和凝胶电泳衍生的肌球蛋白同工型酶联免疫吸附测定（GEDELISA），研究了新生小猫快速伸趾长肌（EDL）和慢速比目鱼肌在出生后发育过程中肌球蛋白合成的变化。所使用的抗体包括针对慢速和快速肌球蛋白重链的单克隆抗体以及针对胎儿/胚胎肌球蛋白的多克隆抗体。在新生小猫的这两块肌肉中，都存在一群更成熟的纤维，它们对慢速肌球蛋白染色强烈，而对胎儿/胚胎肌球蛋白染色较弱。这些纤维被认为是初级纤维。它们在出生时占EDL纤维的4.8%，占比目鱼肌纤维的26%，并在成年肌肉中继续表达慢速肌球蛋白。不太成熟的次级纤维对胎儿/胚胎肌球蛋白染色强烈，这些纤维可分为两个亚群；快速次级纤维，其中胎儿/胚胎肌球蛋白被快速肌球蛋白取代，以及慢速次级纤维，其中肌球蛋白被慢速肌球蛋白取代。在50天时，EDL有大量的快速次级纤维（占总纤维的83%）和少量的慢速次级纤维，后者随着成熟逐渐转变为快速纤维。比目鱼肌中的绝大多数次级纤维是慢速次级纤维，其中慢速肌球蛋白的合成在成年期持续存在。比目鱼肌中有一个有限的快速次级纤维区域，这些纤维在成年期逐渐转变为慢速纤维。有人提出，初级纤维和两个次级纤维群体的出现是由肌源性决定的。
