A low surface tension liquid fluorocarbon, FC-80 (3M Company, St. Paul, Minnesota), was used as a carrier of osmium tetroxide for primary intratracheal fixation of rodent lungs. The fixative rapidly displaced air and preserved the lungs in an inflated state. Free cells were fixed upon airway surfaces as osmium-FC-80 did not wash cells or mucus into the distal lung. This made it possible to quantify the migration of leukocytes into airways. Mitochondria, lysosomes, cell junctions, blood-air-barriers, alveolar capillaries, and alveolar and airway epithelia were well preserved. Smooth muscle myofilaments and the periodicity of collagen were especially prominent. Minor disadvantages, which included deleterious effects on membranes, graininess, and extraction of protein and lamellar body lipids, were minimized by postfixation with buffered glutaraldehyde.
ASJC Scopus subject areas
- Molecular Biology