Korneliussen H, Nicolaysen K
Cell Tissue Res. 1975;157(1):1-16. doi: 10.1007/BF00223227.
Triad density relative to sarcomeres, size of T-system tubules, sarcomere length, muscle fiber diameter in native and fixed states, and size of myofibrils were measured in four straited muscle fiber types in Atlantic hagfishes (Myxine glutinosa, L.) of different sizes. Traids occur at A/I-injunctions in all fiber types. The density of traids relative to sarcomeres is higher in "white" than in "red" muscle fibers. The T-tubules show no sign of branching. The area of the T-system tubules is 3-4 times the surface area in 80 mum "white" muscle fibers and 1-2 times that in 60 mum "red" fibers. The size of myofibrils is similar in "white", "intermediate", and "red" fibers of m. parietalis, and constant through a large span of animal size. In "white" fibers, increase in diameter up to 90 mum is accompanied by an increase in the number of myofibrils, not by an increase in the individual size of the myofibrils. Above 90 mum, "white" fibers grow by increasing the amount of intermyofibrillar space. This is reflected by an extensive shrinkage of the thicker "white" fibers during the preparative procedure for electron microscopy, a shrinkage that is limited only by complete packing of the myofibrils. "Red" fibers shrink much less.
在不同大小的大西洋盲鳗（Myxine glutinosa, L.）的四种横纹肌纤维类型中，测量了相对于肌节的三联体密度、T系统小管的大小、肌节长度、天然和固定状态下的肌纤维直径以及肌原纤维的大小。三联体出现在所有纤维类型的A/I连接处。“白色”肌纤维中三联体相对于肌节的密度高于“红色”肌纤维。T小管没有分支迹象。在80μm的“白色”肌纤维中，T系统小管的面积是表面积的3 - 4倍，在60μm的“红色”纤维中是表面积的1 - 2倍。顶肌的“白色”、“中间型”和“红色”纤维中肌原纤维的大小相似，并且在动物大小的很大范围内保持恒定。在“白色”纤维中，直径增加到90μm伴随着肌原纤维数量的增加，而不是单个肌原纤维大小的增加。在90μm以上，“白色”纤维通过增加肌原纤维间空间的量来生长。这在电子显微镜制备过程中较粗的“白色”纤维的大量收缩中得到体现，这种收缩仅受肌原纤维完全填充的限制。“红色”纤维收缩要少得多。
