Alveolar epithelial surface area-volume relationship in isolated rat lungs
Alveolar epithelial surface area-volume relationship in isolated rat lungs
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DOI：
10.1152/jappl.1999.86.6.2026
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发表时间：
1999-06-01
影响因子：
3.3
通讯作者：
Margulies, SS
中科院分区：
文献类型：
--
作者：
Tschumperlin, DJ;Margulies, SS
肺泡上皮细胞变形反应的体外研究需要了解这些细胞的原位力学环境。由于组织折叠和起皱的存在，先前测量的可用于气体交换的肺泡表面积不等于上皮表面积。为了确定代表体内条件的均匀充气肺中的上皮变形，我们研究了在高肺容量（10-25 cmH（2）O）下循环三次后，在放气时用戊二醛灌注固定的离体Sprague-Dawley大鼠肺（n = 31）。对45张电子显微照片（x12，000）/大鼠的上皮基底膜进行追踪、数字扫描和分析。上皮基底膜表面积（EBMSA）计算从形态学的关系。发现EBMSA相对于24%总肺容量的EBMSA分别在42%、60%、82%和100%总肺容量的肺容量下增加5%、16%、12%和40%。EBMSA的增加表明，上皮细胞经历了显着的变形与大的充气和肺泡基底膜变形可能有助于肺回缩在高肺压力。
In vitro studies of the alveolar epithelial response to deformation require knowledge of the in situ mechanical environment of these cells. Because of the presence of tissue folding and crumpling, previous measurements of the alveolar surface area available for gas exchange are not equivalent to the epithelial surface area. To identify epithelial deformations in uniformly inflated lungs representative of the in vivo condition, we studied isolated Sprague-Dawley rat lungs (n = 31) fixed by perfusion with glutaraldehyde on deflation after cycling three times at high lung volume (10-25 cmH(2)O). The epithelial basement membrane in 45 electron micrographs (x12,000)/rat was traced, digitally scanned, and analyzed. Epithelial basement membrane surface area (EBMSA) was computed from a morphometric relationship. EBMSA was found to increase 5, 16, 12, and 40% relative to EBMSA at 24% total lung capacity at lung volumes of 42, 60, 82, and 100% total lung capacity, respectively. The increases in EBMSA suggest that epithelial cells undergo significant deformations with large inflations and that alveolar basement membrane deformation may contribute to lung recoil at high lung pressures.