Study on the change of lung lamellar body to lattice tubular myelin by N-acetylglucosaminidase with special reference to membrane components and calcium

: The possibility of a role of N-acetylglucosaminidase or beta-galactosidase in the morphological change of lung lamellar body to lattice tubular myelin was examined in an in vitro incubation study. Electron microscopic observation of the incubation product and gas-chromatographic analysis of released sugars during incubation were used to understand the mechanism of these enzymes in the change of membrane constitution. N-acetylglucosaminidase proved to play a role in developing membrane of lamellar body toward lattice tubular structure with the support of Ca++. In this process, inositol release was indispensable in the modulation of membrane as well as the release of a small amount of N-acetylglucosamine. However, further reaction of this enzyme caused destruction or fusion of lattice-tubular integration with the release of other membrane components. Beta-galactosidase played no role in this process.