Abstract
The present study demonstrated the three-dimensional organization of the collagen and elastin fibers of the lung in the Japanese monkeys, Macaca fuscata as revealed by alkali-maceration/scanning electron microscope technique. The collagen fibers, which were bundles of collagen fibrils, were repeatedly divided and fused to form a network along the alveolar duct. The collagen fibers in the alveolar duct branched and entered the alveolar septa, where the fibers again repeated branching and fusing and formed thin networks. Thick collagen fibers around the alveolar mouths took significant degree of zig-zag or spiral courses. The elastin fibers were condensed around the alveolar mouths, but there were also elastin fibers between the adjacent alveolar mouths. Within the alveolar septa were course network of elastin fibers.
