Scanning electron microscope study of the developing microvasculature in the postnatal rat lung

Wiley - Tập 216 Số 2 - Trang 154-164 - 1986
Jürg H. Caduff1, Lisa Fischer1, Peter H. Burri1
1Institute of Anatomy, Section of Developmental Biology, University of Berne, CH‐3000 Berne 9, Switzerland

Tóm tắt

AbstractDuring postnatal growth the parenchymal septa of rat lung undergo an impressive restructuring. While immature septa are thick and contain two capillary layers, mature septa are slender and contain a single microvascular network. Using the Mercox® casting technique and scanning electron microscopy, we investigated the mode and the timing of the transformation of the pulmonary capillary bed. During the third postnatal week the parenchymal septa rapidly mature to match adult morphology. Even in adult lungs, however, remnants of the immature status are present: A capillary bilayer is regularly found at the base and the tip of the septa. Our observations support the concept that reduction of intervening tissue, partial fusion of the two capillary networks, and preferential growth lead to the mature vascular arrangement. The fact that true mature interalveolar septa show a denser capillary network than alveolar walls abutting onto pleura, bronchi, or larger vessels is consonant with the fusion theory. Towards the nonparenchyma, the capillary network surrounding every airspace had no counterpart to fuse with.From quantitative data it can be calculated that owing to lung growth, mesh size should increase more than four times between birth and adult age. The adult lung network, however, is denser than the one in young animals. This means that new meshes must be added during growth. We propose that small holes observed in sheet‐like regions of the microvascuiature enlarge to form new capillary meshes. With this mechanism of in‐itself or intussusceptional growth, sprouting of individual capillary segments to increase network size is no longer needed.

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Tài liệu tham khảo

10.1016/0026-2862(77)90141-8

10.1083/jcb.95.2.394

10.1002/jemt.1060010404

Burger P. C., 1984, Scanning electron micrsocopy of vascular casts in experimental ocular vasoproliferation, Scan. Electron Microsc., 4, 1893

10.1002/ar.1091800109

10.1002/ar.1091780405

10.1002/tera.1420190312

10.1113/expphysiol.1965.sp001772

10.1111/j.1365-2818.1974.tb03977.x

10.1111/j.1749-6632.1982.tb25720.x

Frasca J. M., 1978, An improved latex injection media for replicating the pulmonary microvasculature, Scan. Electron Microsc., 2, 485

10.1016/0026-2862(85)90026-3

10.1152/jappl.1982.53.2.510

Hodde K. C., 1980, SEM of micro‐corrosion casts, Scan. Electron Microsc., 2, 89

Howell P. G. T., 1975, Taking, presenting and treating stereo data from the SEM, Scan. Electron Microsc., 1, 698

10.1159/000410083

Lametschwandtner A., 1984, Scanning electron microscopy of vascular corrosion casts–Technique and applications, Scan. Electron Microsc., 2, 663

Miller W. S., 1947, The Lung

10.1001/archotol.1978.00790060015004

10.1679/aohc1950.32.445

10.1007/BF02810077

Ohkuma H., 1983, Vascular casts of experimental subretinal neovascularization in monkeys, Invest. Ophthalmol. Vis. Sci., 24, 481

Ohtani O., 1980, Microvasculature of the rat lung as revealed by scanning electron microscopy of corrosion casts, Scan. Electron Microsc., 3, 349

Ohtani O., 1984, Review of scanning electron and light microscopic methods in microcirculation research and their application in pancreatic studies, Scan. Electron Microsc., 2, 653

Simpson J. G., 1983, Struktur und Funktion endothelialer Zeilen, 80

10.1161/01.RES.26.3.397

10.1016/S0002-9394(14)75914-8

Vuillemey E., 1984, Vascularisation iridociliaire. Etude par injection intravasculaire de résine polymère, J. Fr. Ophtalmol., 7, 179

Wagner R. C., 1980, Endothelial cell embryology and growth, Adv. Microcirc., 9, 45

Wang N. S., 1976, Scanning electron microscopy of capillary and elastic fiber networks in alveoli, Scan. Electron Microsc., 5, 233

Wang N. S., 1977, A scanning electron microscopic study of alkali‐digested human and rabbit alveoli, Am. Rev. Respir Dis., 115, 449

Weibel E. R., 1977, Lung Biology in Health and Disease, 1

Wolpert L., 1983, Development of the Vascular System, 1

10.1007/BF00341407

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Wiley

Tập 216 Số 2

154-164

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