The change of the lipid composition in the fertilizing egg membrane of Rana dybowskii were studied. It was observed that the relative amount of sphingomyelin increased concominant with the commencement of blastogenesis in two hours after fertilization. However, any significant changes of other lipids, such as phopholipid, glycolipid, cholesterol and simple lipid in fertilizing egg were not observed.
It has known that sphingomyelin exist in all of the animal cells and renders the bilayer lipid structure stable. Sphingomyelin reviewed great deal amount of attention due to the roles of intercalating in the transduction pathway transmitting outside signals into the cell. These experimental data suggest sphingomyelin plays a key role in maintaining the fluidity and stability of the bilayer lipid structure in association with the general condition of mitotic division in rapidly proliferating amphibian eggs.
