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Published on: December 22, 2011
Molecular sieve in bovine descemets membrane as revealed by negative staining
Abstract:
Descemet's membrane was isolated from the corneas of cows and observed by electron microscopy after negative staining with 1% phosphotungstic acid solution, pH 7.2. Ultrastructurally, bovine Descement's membrane had a very regular hexagonal pattern. Nodes were connected to the six others around each of them by thin filaments to form a hexagon. The distance between the nodes was approximately 120 nm, the diameter of the nodes approximately 30 nm, and the width of the connecting filaments approximately 10 nm. Bovine Descement's membrane was a molecular sieve composed of nodes and filaments substantiating our molecular sieve theory of basement membranes.
Insights
Researchers observed bovine Descemet
Area of Science:
- Ophthalmology
- Biomaterials Science
- Cell Biology
Background:
- Descemet's membrane is a key component of the cornea.
- Understanding its ultrastructure is crucial for corneal research.
Purpose of the Study:
- To investigate the ultrastructural organization of bovine Descemet's membrane.
- To provide evidence for the molecular sieve theory of basement membranes.
Main Methods:
- Isolation of Descemet's membrane from bovine corneas.
- Electron microscopy with negative staining using phosphotungstic acid.
Main Results:
- Bovine Descemet's membrane exhibits a highly regular hexagonal pattern.
- This structure consists of interconnected nodes and filaments.
- Specific dimensions of nodes (30 nm), filaments (10 nm), and inter-node distances (120 nm) were determined.
Conclusions:
- Bovine Descemet's membrane functions as a molecular sieve.
- The observed ultrastructure supports the molecular sieve theory of basement membranes.
