Asayama J, Ford L E, Surdyk-Droske M F
J Muscle Res Cell Motil. 1983 Jun;4(3):307-19. doi: 10.1007/BF00711998.
Semitendinosus fibres from Rana pipiens were examined in the electron microscope. When the aqueous solutions in which the fibres were prepared contained no sucrose, the sarcoplasmic reticulum was markedly swollen and possibly fragmented. When as little as 50 mM sucrose was included in the aqueous solution, the sarcoplasmic reticulum retained the flattened appearance characteristic of intact fibres. The degree of flattening was not substantially different with concentrations of sucrose ranging from 50 to 300 mM, suggesting that the flattened volume may be determined by structural elements. In all the fibre segments, the regularity of the hexagonal filament lattice was disrupted and the disruption was not affected by sucrose. Radioactive calcium uptake was measured in the presence and absence of 200 mM sucrose. The capacity of the sarcoplasmic reticulum (SR) was depressed by about 30% by the sucrose but the initial uptake was not significantly affected. This finding suggests that most of the calcium within the SR is bound and not free in solution.
对来自豹蛙的半腱肌纤维进行了电子显微镜检查。当制备纤维时所用的水溶液中不含蔗糖时，肌浆网明显肿胀，甚至可能破碎。当水溶液中仅含有50 mM蔗糖时，肌浆网保持完整纤维特有的扁平外观。蔗糖浓度在50至300 mM范围内时，扁平程度没有实质性差异，这表明扁平体积可能由结构元件决定。在所有纤维段中，六边形细丝晶格的规则性受到破坏，且这种破坏不受蔗糖影响。在有和没有200 mM蔗糖的情况下测量放射性钙摄取。蔗糖使肌浆网（SR）的容量降低了约30%，但初始摄取没有受到显著影响。这一发现表明，SR内的大部分钙是结合的，而不是游离于溶液中。
