Hartfield P J, Williams K E, Geddes R, Lloyd J B
Department of Biological Sciences, University of Keele, Staffs, UK.
Placenta. 1989 Jan-Feb;10(1):45-54. doi: 10.1016/0143-4004(89)90005-2.
The glycogen content of the rat visceral yolk sac was determined between 13.5 and 20.5 days of gestation by the best available colorimetric method. The concentration of glycogen in the tissue increased ten-fold between 13.5 and 18.5 days, to reach a value similar to that for mammalian muscle, but then decreased by 50 per cent between 18.5 and 20.5 days. Determination of the iodine-iodide spectra and fractionation of the glycogen particles by a novel sodium citrate centrifugation method indicated broad similarities between the structures of glycogen particles, isolated by a mild phenol-water method, from the yolk sac and the liver of the rat. However, the proportion of 'high'-molecular-weight glycogen in the yolk sac increases between 18.5 and 20.5 days, as a result of the preferential loss of 'low'-molecular-weight glycogen, so that at term the proportion approaches that found in liver glycogen.
采用现有的最佳比色法测定了妊娠13.5至20.5天大鼠内脏卵黄囊的糖原含量。组织中糖原浓度在13.5至18.5天之间增加了10倍，达到与哺乳动物肌肉相似的值，但在18.5至20.5天之间下降了50%。通过一种新型柠檬酸钠离心法测定碘-碘化物光谱并对糖原颗粒进行分级分离，结果表明，用温和的酚-水法从大鼠卵黄囊和肝脏中分离出的糖原颗粒结构具有广泛的相似性。然而，由于“低”分子量糖原的优先损失，卵黄囊中“高”分子量糖原的比例在18.5至20.5天之间增加，因此在足月时该比例接近肝糖原中的比例。
