AN AUTORADIOGRAPHIC STUDY ON THE UPTAKE OF RADIOSULPHATE (S~(35))——METHIONINE IN THE EMBRYONIC TISSUE VERSUS YOLK MATERIAL OF THE DEVELOPING CHICK EMBRYO
- VernacularTitle:鸡胚发育期中细胞与卵黄对放射性硫(S~(35))—蛋氨酸摄取的对比研究
- Author:
Sherpu SHIEH
;
Isen PU
- Publication Type:Journal Article
- From:
Acta Anatomica Sinica
1954;0(02):-
- CountryChina
- Language:Chinese
-
Abstract:
Saline solution (0.9%),containing 5—10?c of radiosulphate(S~(35))——methio-nine(0.2—0.4ml)was injected into the yolk sacs of unincubated to 8—day chickembryos.Fixation was made after 6—24 hours of incubation in various fixa-tives (Bouin's,Carnoy's,neutral formalin,methyl or 95% ethyl alcohol).Mostof the embryos were stained in toto with Ehrlich's hematoxylin and eosin,butsome were stained with Wallback's Giemsa mixture of Mallory's modificationafter sectioning.Serial sections(5—7?) were used for contrast autoradiography.It was observed that a remarkable radiosulphate uptake in the embryonic tissuefollows the cellular pattern and was concentrated in proportion to the cellulardensity of tissue,the tracer is noticeable in the autographs by its ?-tracts andgrains over cytoplasm and nuclei of cells;while the yolk spheres entered thesubgerminal cavity and in the space between ectoderm and entoderm in thegerm wall were not radioactive.The blood vessels,erythroblasts and the mul-tinucleated syncytium,including the so-called “columnar epithelial cells” of theyolk sac lining and of the germ wall,also show high incorporation of radio-sulphate,but not at all in the yolk material.Furthermore,the yolk granules,droplets of unequal size with positive Feulgen reaction,and those even withan appearence of pyknotic nucleus in the “transitional zone” of yolk sac liningas described in the previous investigation,also show no tracer uptake.It isobvious,that radiosulphate is not incorporated into the yolk material.Fromthe above,it may be assumed that no protein synthesis or resynthesis(“??-????????”) occurs in the yolk sphere.These results are in good agreementwith our previous findings and afford further evidence to the conclusion that theyolk spheres are not a living substance incapable of developing into embryoniccell.
