Three-dimensional reconstruction of tubular myelin.

Journal Article

The lipid and protein components of pulmonary surfactant are synthesized by alveolar type II cells and stored in their secretory granules, the lamellar bodies. Tubular myelin is a highly ordered surfactant structure that is lung specific and produced in the alveolar airspace. Recent work identified Ca2+, surfactant apoproteins A and B, and saturated phospholipids as necessary for tubular myelin structure and function. We have used serial ultrathin sections from fetal rat lungs and reconstructed the three-dimensional structure of tubular myelin. The spheres of tubular myelin we viewed were 2-3 microns in diameter and were surrounded by up to 20 lamellar bodies, each apparently simultaneously contributing material to the tubules. We measured a long-range symmetry of the tubules, which were folded about a central axis and showed a repeated crossing of individual tubes from one side to the other of the large structure. The tubes appeared closed on their outer edges and there was a delay in the penetration of tubules by cationic ferritin added to tissue slices containing the tubular myelin, although within a few minutes tracer appeared in the lumina and on the walls of the tubules. The three-dimensional images were compatible with existing views of tubular myelin.

Full Text

Duke Authors

Cited Authors

  • Young, SL; Fram, EK; Larson, EW

Published Date

  • July 1992

Published In

Volume / Issue

  • 18 / 4

Start / End Page

  • 497 - 504

PubMed ID

  • 1516569

Pubmed Central ID

  • 1516569

International Standard Serial Number (ISSN)

  • 0190-2148

Digital Object Identifier (DOI)

  • 10.3109/01902149209064342

Language

  • eng

Conference Location

  • England