几种家鱼胚胎发育期间液晶态的研究

几种家鱼胚胎发育期间液晶态的研究 OBSERVATIONS ON THE LIQUID CRYSTAL PHASE IN SOME FISHES DURING THEIR EMBRYONIC DEVE LOPMENT 孙建民 Sun Jianmin first-author 本实验观察到四大家鱼胚胎发育期间,在卵黄囊和某些器官原基区有液晶小体存在,并有一定的变化规律。测定了这几种鱼类胚胎发育期间硷性磷酸酶和酸性磷酸酶的活力变化,分析了发育期间脂类变化的趋势。从而可以看出,鱼类胚胎发育期间液晶小体的变化规律和两种磷酸酶的活力变化规律相吻合。试验说明,不但鸟类胚胎发育期有液晶小体存在,而且也见之于鱼类。 According to our preliminary observations the four freshwater species of Chinese carps （silver-, bighead-, grass- and black carps） show the presence of liquid crystal phase in their yolk and developing organs of the embryo. Under the polarizing microscope, the following results are obtained. 1. In the yolk sac, the liquid crystals with apparently characteristic "Maltese crosses" are found as early as the very beginning of fertilization, but in the earlier stages of the embryonic development of the fishes mentioned above, there are only a few liquid crystal particles, which, from the late period of gastrulation, increase innumber and size with the growth of the embryo. At the time of hatching the number of the liquid crystal particles decreases, but soon after hatching, the quantity of liquid crystals reaches its peak in the yolk sac. 2. The amount of liquid crystals in different stages of embryogenesis changes in accordance with the changing activities of the acid- and alkaline phosphatases of the embryo. At the late period of gastrulation the embryo begins to show higher metabolic rate, with the enhancement of the activation power of phosphatases and the increase of liquid crystals. 3. In the fertilized egg liquid crystals first appear at the peripheral region of the yolk sac. Later they are shifted to the part just underneath the embryonic region. In the newly hatched fry, liquid crystals are seen to be carried to the living systems in a definite direction. 4. The thin-layer chromatography shows that the composition of the liquid crystals in the embryo requires lecithin, cephalin, neutral fat, cholesterol and its esters. These compounds change in amount with the development of the embryo. 5. Liquid crystals are also clearly observed in areas of the anlagen of embryonic organs. Maltese crosses concentrate about the developing neural tube, the heart, the myomeres, the gonads etc. From what has been observed, it seems that the liquid crystals play a very important role in the devlopmental process of living systems. 1980-04-01 2021-04-01 4